January 29, 2015

Interior Update: G-Wagon Center Console

Anyone with an older G-Wagon has experienced a center console with holes and cracks. Seems over time, various switches and modifications have been added and removed to many consoles so there are small holes, screw mounts and missing parts. This was the case with my G-Wagon but there was another problem. The center air conditioning unit had been removed leaving the rear of the center console where it was cut looking pretty shabby. 

I thought about getting a new console, but the price was well over $600. I decided covering it with vinyl like the rest of the car would look better and be less expensive. 
Repaired Underside of W460 Console

I asked Ben at Brent's Custom Upholstery to try. He said it would be pricy and take some time, but he would see what he could do. He started by patching the holes and performed a miracle by using ABS plastic to fix the cut out portion so it had the shape prior to the trimming to accommodate the air conditioning console. 

He then covered the console with padding and finished it off with stitched vinyl that had a nice leather look that matched the seats and doors. I opted for black to keep the feel of the original console. One bonus is the new console isolated more noise from the transmission and engine. 

Covered G-Wagon Console

At about $200 this was a better option for me and a huge interior upgrade to the look of the W460 while keeping the original look and design feel.

THANKS BEN!

January 21, 2015

OM 617 Turbo POWER

If you are like me, you have probably never driven a 1984 turbo diesel G-Wagon. They are kind of like Unicorns, we like the idea of them, but they were just never made. Why you ask? First of all, there were no G-Wagons sold in the US in the 80's and secondly the turbo diesel G-Wagon was not even built until the 90's. 
ALDA with Cap In Place

The thing was, the power from the OM617 5 Cylinder Turbo in my car seemed pathetic. Why would anyone want to have this? The term SLUG comes to mind. I was getting 0-60 in something like 30 seconds and forget about a mountain climb at anything near the speed limit. So I started digging for more power. Turns out the first thing I tried, adjusting the ALDA, was just the thing I needed. It was easy and did not take long, required no special tools or instruments and WORKED!


The OM617 Turbo has an ALDA that controls the amount of fuel sent to the engine. The ALDA is a simple mechanical device that that measures altitude of the vehicle and the pressure from the turbo intake manifold pressure to adjust the fuel made available to the engine. I could tell mine had not been adjusted since the engine was assembled at the factory because the cap was still covering the adjustment screw. 

My first step was to make sure the pressure from the intake manifold was reaching the ALDA. I started by removing the nut at the rear of the intake manifold with the banjo connecting to the plastic hose and make sure the airway was clear. It had some build up in the nut and the banjo so I cleaned it with a solvent and replaced it. 

The next step for the pressure from the manifold was a cutoff valve. There is a switch on the top of the intake manifold that measures pressure inside the manifold. Too much pressure and the switch connects to ground and causes a bypass valve to release the pressure before it gets to the ALDA so the turbo will not overload. In my case the wires going to the bypass and manifold switch were disconnected.

Just to make sure, I removed the bypass switch connected the hoses tested it on my bench. It worked perfectly. After checking all the remaining hoses I removed the cap from the top of the ALDA.


ALDA Cap Partially Removed
The top of the cap is plastic so I used a sharp razor blade to cut through the plastic on top and a pair of diagonal cutters to cut the metal along the side ring. This reveled a hex lock nut and the adjustment screw. I kept working at the cap until I could get to the locking nut. By removing the locking nut from the ALDA, I was able to remove the remaining part of the metal ring and plastic.   

Once the cover was removed, I replaced the large washer that was under the nut with the locking nut but did not tighten it all the way. With the nut loose, the screw in the middle was easy to turn. Do not force the screw, it will break! I turned the screw counterclockwise about 1/8 of a turn to increase the fuel flow and took the car for a drive. I tightened to hex hut to hold the screw in place. WOW what a difference. Much better acceleration below 2000 rpm and a HUGE improvement once the turbo kicked in. 


I repeated the steps above and adjusted it one more time and got another increase in acceleration and responsiveness. I was careful not to adjust so far that black smoke came out of the exhaust indicating too much diesel to was being provided for the the engine to burn.

The next step was to get the overload bypass working again. I simply installed the bypass switch and reconnected it to the manifold overload switch. Unlike what some other said, I experienced NO LOSS OF POWER by replacing the properly working pressure release switch. Most importantly the engine is now protected from turbo over boost. Even with the overbuilt nature of the OM617A, too much turbo could damage the engine.  

There is a lot of talk on the internet about whether or not to adjust the ALDA. Some even say you should completely remove the ALDA. Others turn the screw all the way out till it stops. I think my results speak for themselves. The car was a slug prior to the adjustment and now it is downright zippy with 0-60 now less than 22 seconds that is almost a 30% increase in acceleration. My feeling is a 30 year old mechanical device could use some adjustment.

One more note: I also performed a Diesel Purge that provided more of a performance boost. CLICK HERE for detail instructions. 

If anyone wants to drive a 1984 300GD Turbo, just take a short drive to Park City and I'll let you take it for a spin. Because unlike the mythical unicorn, they really exist. Warning: after driving the turbo, you will hunting for an OM617 Turbo to put in your W460!

January 9, 2015

Interior Update: Modified Recaro Seats

Original Tartan W460 Seats
I'm not looking to restore my 1984 300GD. If I were looking to have an original G-Wagon from the 80's, this would not be the car. First of all it was built as a 280GE, now it has an engine from a 1985 300 Turbo and a totally different transmission. On top of that, it was repainted a modern Mercedes Onyx color. I'm looking for a Snow Wagon to be a winter driver here in Park City so a seat upgrade was in order. 

When the 300GD came with two sets of seats, my choice came down to comfort and looks. A set of Recaro racing seats had been installed by a previous owner. He made some custom adaptors that were basically two steel square tubes that ran down each side of the seat. Also included were the original seats with that checkered fabric. They actually looked pretty good but did not even come close to comfort of the Recaro. 
Recaro Racing Seats

The thing is, the Recaro's are racing seats similar to the Recaro Speed series but with larger, and to me very ugly wings on the sides. The Speed Series are designed to accommodate racing restraints that would come over each shoulder and latch between the driver's legs. We may do some off road driving in this car, but there would be no need for racing restraints. Looking them up on Recaro's web site, I could tell the current version of this seat sold for about $900 each. I decided if I could make them look a little less like a racing seat, I would go with the Recaro. The original seats would be bound for an eBay auction!

While I did most of the interior work myself, I was not about to take on the job of upholstery work on the seats. For that I decided to use a local shop in Heber City, UT called Brent's Custom Upholstery. They said they could recover the seats, trim down the wings, remove the plastic rings and fill in the seat restraint holes. They recommended covering the front of the seats with the more durable and breathable leather and use the vinyl for the backs. Turns out this is how most "leather" factory seats are covered. 
Covered Recaro Leather Seats

When covering the old rear seats, I decided to focus on two passenger look rather than three. I had some 1" padding added to add definition to better match the pattern on the front seats and stuck with vinyl to reduce the cost. I asked them to add some ABS plastic to the otherwise metal back of the rear seat and had it covered with HR1307 Harddura. For those not familiar with Harddura, it is a strong vinyl backed with heavy felt that was used as interior floor lining in English cars, mostly Jaguars of 60's and 70's. Since I was planning to use it as the floor covering for the back of the car and under the rear bench seat, it made since to cover the back of the bench seat with the same material.

I already had the lather and matching vinyl so pulled out the Recaro front seats, the back bench seat and installed the original seats so I could continue the rolling restoration. I also dropped off some ceramic heating elements for the front seats to be installed. About 6 weeks later and the seats were done and they looked great. 

The seats are comfortable look fantastic and the rear seats look very much like the W463 seats shipping in the newer G-Wagons. I really like the upscale stitching pattern that Brent's used and it matches the stitching on the doors. While not accurate as an example of a W460, with the interior done, folks can't believe this car was made in 1984. To me it is comfortable to drive and does not deviate much from the original design.  

January 7, 2015

Slipping in 4th - Transmission Trouble?

Last week after I got the oil changed, I noticed the transmission slipping in 4th when climbing hills. I called my local Mercedes guru Brent Groth and asked what he thought it could be. He had this worried sound to his voice and said, "that is not good." I had the transmission oil changed and a new filter fitted in Burbank just about 6 weeks ago so I was a bit worried. 

I see from records that the previous owner provided that he installed a rebuilt 722.109 automatic transmission from Sun Valley Mercedes Transmissions in December of 2008. That is the same transmission that was used in the 300D from 1957-1981. Checking the records of when the car was built using a European VIN Decoder, it looks like the car was originally fitted with a 720.109 4-speed automatic transmission.

Since I need to have the front and back master cylinder boots rebuilt anyway, I decided to have the transmission looked at. I took the car to a place in SLC called Transmission Man (I'm not making that up), gave Ben all the info I had and asked them to take a look at it. He had his folks look the car over and while they are good at what they know, he asked me to come down and go over it with him. 

We started by looking over the vacuum system and tested the Vacuum Modulator with a hand pump and gauge. With our setup, it would not hold pressure indicating a ruptured diaphragm. The "red" Vacuum Modulator used in the 722.1xx transmissions seems to be hard to find, but we found one at Ecklers and ordered it. 


Once the new Vacuum Modulator arrived, I removed the old modulator and about a quart of transmission fluid drained out from the hole. Once the modulator was out, I pressure tested it again and it held pressure perfectly. My guess was the test rig performed by Ben and me had a leak. Since I had a new modulator, I pulled the pin from the old modulator and adjusted it to have approximately the same length. 

Once the new modulator was in place and I added back the quart of transmission fluid, I used the supplied key to adjust the shift points. Note: The correct way to adjust the modulator is to measure the pressure from the transmission pressure port just next to the modulator, but I did not have the equipment to do that.

I then noticed the vacuum modulator was connected to the VCV vent valve. The VCV vent should vent into the car cabin and not be connected to the modulator. I installed a new T to the hose at the top of the VCV and connected it to the Vacuum Modulator. I purchased an OTC 5613 Vacuum/Pressure Gauge Kit and tested the vacuum coming from the top of the VCV and it was within spec at 15 in Hg and dropped to 0 in Hg at full throttle. 

The result, shifting much smoother but still slipping in 4th. With all of the pressure points going to the transmission good, I've done all I can do without pulling the transmission.
Ready to Travel to LA

I put in a call to Sun Valley Mercedes Transmissions and Marc said he knew exactly what the problem was. Apparently, there is a valve in the transmission that dramatically reduces the pressure when the transmission shifts to 4th. His guess was valve needs to be replaced and said because it has been slipping that a rebuild is probably in order. Brent at Transmission Man in SLC said he could rebuild it but since I'm going to LA this week thought it would be best to let a Mercedes Transmission expert do the work. Brent pulled the transmission and loaded it in the back of my car for the trip to LA.

My Rebuilt 722.109 Transmission
When I dropped off the transmission at Sun Valley Mercedes Transmissions, Marc said he had never had a transmission he rebuilt come back before. He took a look and as he suspected the valve and spring needed to be replaced. After about three days, I came to see him test the transmission. They basically rebuilt it again, cleaned it up, gave me the correct dipstick, washers for the banjo on the dipstick tube and a new Bowden cable. I had to admit the transmission they loaded up in my car looked new. All this for a very fair price!

I loaded the transmission back into my car on my next trip to Park City where the folks at Transmission Man put it back into the car. The guys at the shop did not really know how to adjust the modulator or Bowden cable, but the process of testing the vacuum and throttle taught me how to perform the adjustments. 

Once I adjusted the vacuum modulator and Bowden cable, all is well again. Well except, I'm out about $1000. 

January 3, 2015

Baby it's (too) Cold Outside... for my G-Wagon

Living in Park City it can get cold so that classic great American song holds true here. We actually love the cold here because this is a ski town and our economy is based on folks wanting to ski on hundreds of inches of snow. That being said the weather is usually pretty good with bright sunny days and highs in the mid 20's to low 30's and with the low humidity, it is very nice in the winter. But once in a while, we get those arctic blasts and the temps can go very low. That is exactly what happened last week when the temp dropped below -12 F. 

My G-Wagon is a 1984 280GE who's previous owner had a 300CD turbo engine put in it. The G-Series of that era could be purchased with the OM617 engine, but none were made with the turbo option until the 90's. But Mercedes-Benz did fit some of the sedans of that period with the OM617 Turbo, an engine that still has a cult following today.

The problem is, at -12 F the 280 dual overhead cam gas engine would fire right up. I know this because we have a 1984 280 SL and as long as the coolant and oil are correct for low temps, no problems starting the car in the winter. Not so much with the diesel, as it has no spark plug to ignite the fuel. Diesel ignites from heat generated when it gets compressed. Glow plugs help, but when it is very cold, the fuel just does not get hot enough so... no combustion.  

I'm not new to diesel as my Kubota tractor has a 3 cylinder diesel and while it is hard to start when very cold, as long as I keep a winter blend of fuel and add a little winter treatment I don't have trouble with fuel gelling. Even then, on the coldest mornings, the tractor is very hard to start.

That is why I was surprised when I had trouble starting the G-Wagon when it was parked outside overnight. When keeping it in the garage heated at 50 there is no problem, but when parked outside overnight and the temp goes below 20, it is nearly impossible to start. Last week, when it dropped below 0, there was no way it would start. I had to tow it into the garage with the tractor and let it sit overnight, only then did it crank up. Yes, the tractor started but the Mercedes would not!

I checked the glow plugs with cables and all are reading .7 OHMs. That is a shame because Bosch 80006 Duraterm plugs are only about $10 each -- that would have been on an easy fix. I also checked the relay and am getting 11V on each of the five wires leading to the plugs and it correctly drops to 3V after the initial warm up. Additionally, the glow plug relay was even staying on longer when it is very cold. To bad because I can fix just about any electrical problem

I was beginning to think my plan to use a diesel as a winter car was a mistake. If you ask my wife she will say it WAS a mistake. When I started looking for a G-Wagon I wanted the peppier 280 anyway so now I'm feeling like the 280 would have been a better choice. I was not ready to give up!

Convinced the car was working as it should, I started looking for an engine block heater. For those of you who are not used to being in very cold climates, engine block heaters warm the engine block by either heating the oil or the coolant for easier starts, shorter warm-ups and less friction on the engine. 

Zerostart Engine Block Heater
The OM617 engines shipped to the states were fitted with an integrated engine block heater. So I looked under the exhaust manifold where the OM617 should have the heating element and all I found was a large plug. No heating element. I guess the California cars including my engine donor did not get the heaters.

Mercedes owners are used to great parts availability and you can get a OEM Part #: 606-200-00-94 or 900-203-48-95 for about $120. Turns out there is also an aftermarket unit called the Zerostart PN 310-0105 Engine Block Heater that fits most older Mercedes-Benz engines and you can get it from Amazon for about $45. 

Glow Plug Reamer
Before installing the block heater there were two things I did to make the engine run better that just happen to make a big difference with the cold starting issue:

First I removed the old glow plugs and reamed the chambers. This sounds easy, but took some time. You will need to remove the wire nut from the old glow plug, remove the old glow plug, install and remove the reamer until it does not bind, vacuum out the hole, clean, lubricate and replace the glow plugs. There was quite a bit of carbon build up in the chambers because the reamer was hard to get in the first time. The build up had to dramatically reduce the effectiveness of the glow plugs.

The second thing I did a diesel purge to further clean the carbon from the entire fuel system, including the prechamber. I did this to clean the fuel system and deliver more power. CLICK HERE for detailed instructions on the purge process. 

Those two easy steps helped the car start better in the cold and so far the car starts with no issues even when it is in the low 20's. I'll do a test on the next extreme cold night and report the results. 

Back to the block heater because even though it does start in the cold now, I know there will be those crazy cold days and a preheated engine will start with less wear and tear on engine components even when it is not Arctic cold. 

I attempted to remove the plug to install the block heater. I treated the area around the plug with a penetrating lubricant in advance. Then I put a 19MM hex socket on a 1/2 driver and even with a long pipe could not get the plug loose. Since the reamer and the diesel purge improved things so much, I decided the block heater could wait.  

Update 11/12/15 it was 17 degrees this morning and I forgot to put the cold weather treatment in the G-Wagon. I left it outside overnight and after two tries, it started right up. I believe the diesel purge and the reaming (cleaning) of the prechambers where the glow plugs are installed made the difference. After this latest test, I'm no longer worried about the cold winter of Park City... baby - it's not too cold for my G-Wagon and I've become quite happy with the 300G Turbo

November 29, 2014

Heated Seats

My kids love heated seats - maybe it is just the lights on the switch. Every car time they get in the car during the winter, they go for the button! I never used them that much but can kind of see their point when it is super cold. So I thought, "My seats are being reupholstered, I wonder how hard it would be to add the heating elements to the seats?"

Turns out not that hard and not that expensive!

I did a little research and found a kit had everything I needed to retrofit my seats all for less than $70. The kit came with two pads for each of my front seats, switches, relay, cable and fuses. I ordered the kit and took the heating elements to the upholstery shop to be installed before putting on the new leather. 

Then I started working on the wiring. The switches could be mounted in the center console and had cool indicators for high and low settings. The thing is they don't look like the G-Wagon switches. Turns out if such things matter to you, the original MB switch will work. Vlad at Four by Four Club sells just about every switch made, but I could not find the seat heater switch. Turns out he sells a retro fit seat heater kit as well. For $185 he he will sell you a kit that does one seat. 
W460 Heated Seat Switches

I called Vlad and he sold me just the switches for about $75 each. Now you don't need these switches, but the mount in the dash with a little cutting and look stock. 

I tied in the power to the ignition so the seats only worked when the ignition is on because they can draw quite of bit electricity and leaving them on will drain the battery.

I finished the wiring, ran the cables from the dash, down under the center console to the seats. When the seats came in, I simply mounted the relay under the seat and plugged them in being careful to dress the wires so they were clear of all the moving parts. They worked real well.

Now on the cold days, I just reach up on the dash and the cold leather turns warm when it gets hot, I turn it down to the lower setting. Heck, I may even use them in the summer!

November 26, 2014

Interior Update: G-Wagon Doors

After getting all the materials for the interior, I decided to split the work. I removed the door panels, interior trim, floor matting and seats and installed the original seats in the car so I could continue to drive it. I decided take the Recaro Racing Seats, back bench seat and door panels to a local upholstery shop called Brent's Custom Upholstery while I focussed on the headliner, carpet and remainder of the interior panels.  

G-Wagon Door with Dynamat
With everything out of the car, it sounded like a tin can. One of my goals was to reduce noise so that meant treating the interior. With everything out of the car, now is the time. I ordered some Dynamat and Dynaliner to deaden the tin can sound and insulate from the weather. I know they Dyna products are expensive, but have used them in the past with excellent results. The Dynamat sticks great and the Dynaliner is a closed foam so it will not absorb or retain moister. 

For the doors I focused on sound deadening the metal and used Dynamat on the interior metal. I had the upholstery shop put 1/4" Dynaliner on the trim panel before covering them. I did this on all three doors. I also added some Dynamat on the interior of the outer skin. After adding the Dynaliner the doors closed with a solid thump. They now sound like, well... a Mercedes.

Vapor Barrier on G-Wagon Door
I had decided to upgrade the interior but keep the general feel of the original design. I did not like the checkered fabric so that was going. I did like the utilitarian look of the older G so there would be no dramitic upgrades toward a 462 look. My wife and I both agreed the Recaro seats looked strange but they felt great. The original front seats would be sold on eBay. So the interior trim panels would be covered entirely with MBTex with stitching to match the seats. 

I noticed that the interior of the trim panels showed some marks caused by water. Most new cars place a water barrier between the inside trim panel and the door. I cut thick plastic sheeting so size, taped off the edges and sprayed the interior of the door and the plastic sheet with 3M 80 Spray Adhesive. Once tacky, I applied the plastic to the door and allowed the plastic to hang on the inside so any water would just drain out the bottom of the door. 

Then I mounted the interior trim to the door, replaced all the hardware and mounted the pocket. the pockets were cracked and did not look so good, so I asked the upholstery shop fix the cracks, cover them with the MBTex Vinyl and add matching stitching along the top of the pockets. I could have done all of this myself minus the stitching, but I wanted them to match the seats. 

I could have left the locking door hardware off since the doors automatically lock when I start the car, unlock when the car is turned off and I even have an interior power lock switch. I decided that the hardware to manually lock and unlock the door should be installed but decided to ditch the red hardware and get black hardware to match the rest of the interior.

Covered G-Wagon Door Pocket
Now all three doors look great, keep the cold out and sound great when closed. There is a noticeable reduction in road noise. The biggest surprise was how the cold air was kept out of the cabin. I did not realize how much cold air was leaking through the doors. I love the classic and updated look and know water will not be a problem on the recovered panels.  



November 15, 2014

Keyless Entry

After getting back to Park City, my daughter and I went for a ride and she asked what I was doing putting my key in the door. I really never gave it much thought because all of my other classic cars don't have keyless entry, but I was using this as a daily driver. It is really kind of a pain unlocking each door. 

That got me thinking, how hard is it to install keyless entry into a car? The door panels were already off to lube the windows and so they could be recovered. How hard would it be? Turns out, not that hard at all. Here is what I did.

First you need door actuators. Basically these are push/pull devices that hook up to your door locks, mount to the doors below the locks and push up with a positive 12V DC power and pull down when the polarity is reversed. heavy duty actuators are really not that expensive. Universal Car Power Door Lock Actuator can be purchased on Amazon for as little as $5.00 each.

The thing is, you will still need relays, inside switch and if you want it to be remote, a radio receiver and dongle. Turns out, there are some alarm options that provide the entire kit in one package. Two dongles, a receiver, 4 actuators and even an alarm. I selected the CrimeStopper SP-101 Car Security Alarm & Keyless Entry System with (4) Car Power Door Lock Actuator Motors form Amazon for about $45. I also got 6 SPOOLS 100' Feet 16 GA Gauge AWG Primary Remote Wire Auto Power Cable Stranded from amazon to run to each door. 


Bellows on Driver's Door
The hardest part was not mounting the actuators, it was getting power into the doors. My front doors never had power so there is no accordion to run the cables. This meant creating a 1" hole on the door and the jam, priming and painting it then installing an accordion. Euro Truck Importers sells the Mercedes Door Wiring Bellows PN: 1238210697 for about $5.25. That allowed me to run the two wires into each door for the actuators. For the back door, I just snaked the cable through the existing wiring harness. 

It was very easy to install the actuators. I pulled off the door handles by removing the bolts to expose the lock. There I just attached the clamp that came with the actuator on the end of the locking plate. It took some work but it just fit. Then I installed the rod and mounted the actuator near the bottom of the door, drilled two small holes, primed and painted the holes and mounted the actuator on the inside of the door. I tested the actuator with a 12V DC supply before moving onto the other doors.


Wiring Diagram for Alam and Power Locks
I then installed the keyless controller behind the panel next to the ignition switch and added an Installer Essentials Dual relay behind the glove box to control the power locks. I wired the alarm to the L&R parking lights and even came up with a way to have the dome light come on when unlocking the car. This required and additional relay and a diode. (See diagram) I was able to tap into all of the wire I needed to access from the fuse box under the dash on the driver's side. I installed a new fuse box for constant 12V DC behind the glove box for the alarm, power locks and new subwofer amp. The alarm siren was installed under the hood on the drivers side. 


Behind glove box, showing sub amp and lock relay. 
When done, I ran wires under the carpet from the front of the car, along the lower door jamb, up the side pillars, through the side of the car to the rear door. I also ran new speaker cable at the same time for the rear speakers. The controller for the alarm was installed behind the dash panel near the ignition switch and the door relays behind the glove box. I found letting the antenna from the alarm hang down under the dash extended the range of the keyless entry. I repurposed one of the spring switches in the dash and use it as an interior lock/unlock switch. Make sure this is a spring loaded switch as leaving the locks in the locked or unlocked position will drain your battery and burn out the actuators. 

I'm SOOO happy I did this. Now it is easier to find my car in a large lot, easy to unlock all the doors and they automatically lock when I start the car! Most importantly, my daughter does not look at me strange when I unlock the car!

Interior Update: G-Wagon Carpet

Interior G-Wagon
When I got my 300GD, the previous owner had removed all the vinyl interior floor covering and painted the floors with what looked like bed liner. It looked pretty cool... but (and this is a big but) it was LOUD. On long drives, it was also kind of hot underfoot. Pretty cool for 4-wheeling with your buds on the weekend, but for a daily driver, it is a non-starter. 

Something had to change. For me there were three issues:
  • It had to isolate and reduce cabin noise
  • It needed to better insulate the interior from heat and cold
  • It needed to look better
I had already decided on going to MB colors from the 80s and picked up some German Wilton wool carpet from Veteran Company in LA so the decision for the top layer was set. What was needed next was provide a good foundation before laying down the carpet.


Dynomat and Dynoliner
Dynamat with Dynaliner Padding Partially Installed
Since the interior was already out I started by covering the front starting at the firewall and continuing under the front seats with a layer of Dynamat. This is a great sound deadener and heat shield. I cleaned the surface with alcohol to make sure the Dynamat would adhere to the floor. I then cut it to size, removed the backing starting from the front, lined up the product and continued to pull the backing off as I worked toward the back of the car. I used a hard roller to make sure the Dynamat made contact with the entire floor surface.

Like when I covered the doors and roof, this made a huge improvement in the "tin can" feel of the car. It seemed more solid and muted the sound of the engine and transmission. It also was an excellent heat barrier. There was still more to be done. 

Before installing carpet, I needed to put down some padding. Once again, I used Dynaliner. While just about any foam or padding would work, a nonporous material is best used in a car. If padding or carpet gets wet and can absorb the water, it will sit against the metal and start to rust. Wet padding is also prone to mold and mildew. While Dynaliner is expensive, it uses a closed cell foam with a very good self-adhesive backing.

I applied Dynaliner everywhere there would be carpet. This included the firewall, floors of the passenger area, the center transmission hump and the rear wheel wells. This dramatically reduced the interior noise in the car. Engine noise was reduced, as was the transmission wine and the sound from the rear wheel wells.

I then used the original vinyl floor mats as templates to cut the carpet. I placed each carpet piece in the car to make sure the fit was perfect. Then I had the edges of the carpet that would be exposed bound so it would look nice and would not unravel.


Once complete, I applied a coating of Scotch Guard to all the carpet. Then I put a coat of 3M Hi-Strength 90 Spray Adhesive to the surface for the Dynamat and the back of the carpet. Once tacky, I started to apply the carpet. Carefully cutting holes where seats, console and seat belts would be mounted. I then screwed in the door sills and mounted the seats.

While no serious 4x4 would have carpet, in my case the carpet absorbs and isolates cabin noise, looks nice and compliments the rest of the interior. While the W460 may not have come with this type of carpet, it is consistent with the color and type that was delivered on MB cars in the 80's so for me it is in keeping with the period and a nice upgrade. Now that the work is done I am a practical realist, so there are some pretty heavy duty floor mats protecting the carpet!         

November 14, 2014

G-Wagon Tunes!

Early G-Wagons suffer from a lot of cabin noise so getting a good music experience is really difficult. The first step is to reduce cabin noise (see other posts), the second is to get a good stereo that will overcome the noise and provide good balanced sound. 

My brother Paul and I used to run a couple of high-end stereo stores in Atlanta so I've got a little experience with car sound. The first thing you need to know is, unlike cars made before 2000, most modern cars have really good sound systems. The second thing is getting good sound into older cars does not have to be expensive if you do a little DIY. The final and most important thing is to make sure you design the system for the interior of the car and what it needs to do when the car is running. That means listening to speakers in a showroom may not be the best idea.

For any car, the system should be more bass forward than a home system to have a good experience in a running car. That is because the rumble from the engine and road noise provides a lot of low frequency interference. Your ears will start to ignore that sound so your stereo will need to be able to overcome that low end noise and make up the natural attenuation of your ears. Listen to any car system with the engine off then go for a drive and you will see what I'm talking about. 

From the factory, the early W460 has the ability to support 4x6 speakers. Two in the rear pillar and two in the kick panels up front. Frankly, I don't believe 4x6 speakers will cut it. A previous owner had installed 4" speakers in the lower part of the dash on each side, not unlike what Mercedes was doing to just about every car in the 80's.

After pulling all the interior out of the car I decided that the rear pillars could take a 6.5" component speaker system, and I could add two more 6" dedicated woofers in the front kick panels. I decided to change the head unit to support Bluetooth music, had an output for a subwoofer and kept with the German theme. That meant Blaupunkt, although you can choose any single DIN stereo. Another G-option are head units from VDO.


The rear pillars were very easy to put the 6.5" component system. Since I was recovering the interior, I simply cut the holes making sure to have enough clearance then cover with MBTex. The thing about the rear pillars for speakers, is that the cavity behind the speakers rings like a tin can. Without deadening the metal and putting in some sound treatment, any speaker would not produce that solid bass or clear midrange needed for good sound. Do you have a W460 handy? Go back and knock on the outside next to your rear door. Hear that ring? It needs to GO or your stereo will not thump!

Like the doors and roof, I covered the entire rear pillar exterior metal with Dynamat and Dynaliner. I also stuffed it with Fiberglass prior to installing the panel. After applying the treatment, the enclosure was solid and as dead as any quality speaker cabinet. 
Rear Pillar Stereo Speakers

Then I mounted the component speaker system in the rear pillar area making sure to place the tweeter high enough to clear the back seat. For the rear speakers I selected the Kenwood KFC-P709PS 6.5-Inch Performance Series Component Speaker System for about $60. The woofer of this system is not very deep and that is important because there is not much clearance there. Mounting the speaker lower provides better clearance, but even then I needed a spacer ring to make it work. For that extra finished look, I painted the grill of the woofers to match the trim of the car. 

I put an inline capacitor in the existing Kicker front speakers to keep the bass that the speakers could not reproduce anyway from overloading the speakers. With a 4 ohm speaker, I decided to use a 200uF 100V Non-Polarized Capacitor that would roll off at about 3db per octave starting just under 200 HZ. Not only would the reduction of bass signal going to the speakers allow them to play louder without breaking up, it would eliminate any potential low frequency phase issues with the near by woofers installed in the kick panels. 


Subwoofer in Front Kick Pannel
Then I got a couple of $50 6" woofers and installed them in the kick panels. That required some cutting into the metal behind the kick panel. Cutting the thick steel ended up being the hardest part of the entire job. No wonder these cars are so heavy. Additional sound deadening treatment was installed behind the kick panels.

I installed a $40 Pyle PLMRA120 2-Channel amplifier on the back of the dash just under the glove compartment. I took the subwoofer output from the head unit, split it with a Y connector and sent it to both channels to the amp. I routed the amplifier power from a new constant 12V fuse box installed behind the glove box and the trigger power from the head unit. 

I chose to use the Blaupunkt Toronto 420 BT head unit as it had plenty of power to drive the front and rear speakers, two USB ports with iPod support, CD player, and Bluetooth all for less than $150. I installed to to the existing wiring including a trigger for the dash lights so the Blaupunkt would dim at night.

After it was all done, It took a while to tune the parametric EQ and subwoofer output but once adjusted the final system plays nice and loud, has clear highs and nice bass. Most of all, it looks pretty nice.

Most folks really don't care about a nice stereo on an older G-Wagon but this is my winter daily driver, and I needed my tunes. The bonus was that only $300 the entire system came in well under my $500 budget.