I noticed some fluid from the back of my car in late August of 2015. A quick whiff and I discovered it was diesel fuel. DANG! This is the summer of front-end repair, a new starter, and now a leak in my fuel line.
A few days later I decided to take a quick look and the fuel was leaking from where the folks who did the conversion from gas to diesel took the fuel pump out. There was an extra filter and an adaptor. EASY - WRONG! It looked like the fuel was coming from the top of the tank and dripping down. It could be the rubber hose but I decided to remove the tank and make sure.
Here is what I did:
- Run my truck to almost empty.
- Disconnect my battery (no power, no sparks, no boom)
- Removed the rear mat to get to the floor.
- Removed the four philips screws that go to the square panel in the middle and remove the plate.
- You will see a plug with three wires going to the tank, remove the plug. (If you like you can remove this unit and pump your fuel out at this point)
- Also, remove the breather hose that goes to the top of the tank.
- My truck features the extra two tanks in the side pillars so I jacked up the car, removed the clamps from the large hose that goes to the lower tank and disconnected the hoses. You will need to squeeze them to get them off. Then lower the car back down.
- Then I removed the lower hose that feeds the fuel system and drained the tank into a diesel container. (Note this will not remove all the fuel)
- I then removed the return fuel line at the top of the tank.
- I then placed a hydraulic jack under the skid pan and jacked it up just enough to hold the tank in place.
- Two metal straps are all that hold the tank, so simply remove the 13mm nuts and remove the straps.
- Now slowly lower your jack and the tank will start coming out back first. Watch out not to spill the remaining gallon of fuel.
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| Rust on Bottom of Old Tank |
If you have an early model G-Wagon you probably know about the plastic tank conversion. Quick summary: for about $1200 you can purchase a new plastic tank and for $1800 more the kit to install it. The upgrade is a good idea because plastic is better than metal for a BUNCH of reasons. Before we talk about what I decided to do, let me give you some important HARD TO FIND info that will save you money and time.
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| Original Tank From top back |
- The Mercedes part number for the new Plastic Tank for the W460 and W463 is A4604701201.
- The Mercedes part number for the installation kit is A4614700004.
- You can get an after-market part for a LOT LESS from a parts supplier in Latvia at: https://plasticautotank.com/ € 539.25 for the tank and does not require a kit. Even with freight of €599.00, it is half of what they sell for in the States!
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| New Plastic Tank A4614700004 |
I've got a couple of classic cars and decided to look at fixing the tank and maybe getting a new plate made. I know fellow car enthusiasts who have had major tank work and they look great and work for years.
The folks I found locally (State Automotive) use a process called Renu. The tank is cut open, sandblasted inside and out, holes repaired, and sealed with special Renu coatings. They look great and are sealed in a way where they will virtually never rust. The entire process cost just over $500 and in two weeks I had a virtually new tank.
They pulled out all the dents and with the new finish the tank was tough and solid. Actually, I think it is now better than new and should resist all corrosion. They even said there was a lifetime warranty for as long as I owned the car. The best part, it was an exact fit.
I purchased all new hoses, new clamps and sanded down the straps and applied primer and three coats of paint so the straps would look as good as the tank. I installed the tank without the old rusted skid plate for now and it looks and works great.
If you are doing this yourself, make sure you keep the inside of the tank clean, don't get the supply and return on your diesel lines reversed and make sure all hoses are well clamped to eliminate the risk of any air getting into the fuel lines. Once installed you may need to use your diesel primer pump to prime the fuel system.
One more thing to check: After the installation of the new tank, my return lines were seeping at the joints and I was getting a lot of black smoke. I pulled off the return line from the engine and applied some pressure and found the fuel was not going anywhere. The return line was clogged and since the seeping was all the way at the tank, it had to be in the tank. I ran the tank to almost empty, removed the line going to the tank and used a thin flexible wire brush to clear the line. When I first inserted the brush, there was a lot of blockage, but with a little pressure, I was able to clear the line. The car instantly ran better and all of the seeping stopped.
With the tank reconditioned and installed, it was time to start thinking about the skid plate that covers the bottom of the fuel tank. The skid plate for the metal fuel tank and the plastic tank are different and don't look to be interchangeable. Four by Four Club is the only place I found the old-style plate and it is expensive, like $550. CLICK HERE for the plate for the gas version I believe it will work for the diesel as well, but a quick call to Vlad will verify if it works for the diesel tank. ORC also makes aluminum front and back skid plates for the W460 and W463 G-Wagons but they are designed to work for the new plastic tanks as well.
I decided to visit a local sheet metal shop, Sheet Metal Fabricators, and see what they could do. Showing them the rusted rear skid plate they said they could fabricate one for less than $400. He could not reproduce the grooves but otherwise, it would work perfectly. I asked if they could make it from aluminum and they said it would not cost much more. Lead time: two months. When complete, I'll have it powder-coated red just for fun and it will be as nice as the ORC versions.
Stand by for results.
The folks I found locally (State Automotive) use a process called Renu. The tank is cut open, sandblasted inside and out, holes repaired, and sealed with special Renu coatings. They look great and are sealed in a way where they will virtually never rust. The entire process cost just over $500 and in two weeks I had a virtually new tank.
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| Reconditioned Fuel Tank |
I purchased all new hoses, new clamps and sanded down the straps and applied primer and three coats of paint so the straps would look as good as the tank. I installed the tank without the old rusted skid plate for now and it looks and works great.
If you are doing this yourself, make sure you keep the inside of the tank clean, don't get the supply and return on your diesel lines reversed and make sure all hoses are well clamped to eliminate the risk of any air getting into the fuel lines. Once installed you may need to use your diesel primer pump to prime the fuel system.
One more thing to check: After the installation of the new tank, my return lines were seeping at the joints and I was getting a lot of black smoke. I pulled off the return line from the engine and applied some pressure and found the fuel was not going anywhere. The return line was clogged and since the seeping was all the way at the tank, it had to be in the tank. I ran the tank to almost empty, removed the line going to the tank and used a thin flexible wire brush to clear the line. When I first inserted the brush, there was a lot of blockage, but with a little pressure, I was able to clear the line. The car instantly ran better and all of the seeping stopped.
With the tank reconditioned and installed, it was time to start thinking about the skid plate that covers the bottom of the fuel tank. The skid plate for the metal fuel tank and the plastic tank are different and don't look to be interchangeable. Four by Four Club is the only place I found the old-style plate and it is expensive, like $550. CLICK HERE for the plate for the gas version I believe it will work for the diesel as well, but a quick call to Vlad will verify if it works for the diesel tank. ORC also makes aluminum front and back skid plates for the W460 and W463 G-Wagons but they are designed to work for the new plastic tanks as well.
I decided to visit a local sheet metal shop, Sheet Metal Fabricators, and see what they could do. Showing them the rusted rear skid plate they said they could fabricate one for less than $400. He could not reproduce the grooves but otherwise, it would work perfectly. I asked if they could make it from aluminum and they said it would not cost much more. Lead time: two months. When complete, I'll have it powder-coated red just for fun and it will be as nice as the ORC versions.
Stand by for results.
