WANTED 500e gas tank

[500e702u]

Hello fellow 500e fans .
I recently purchased a 500e from a member in Toronto.
I've been enjoying the car until the dreded gas smell in car and trunk .
So I'm looking for a good gas tank .
Any info or or leads would be appreciated
Adam

 

[gsxr]

Forum member @david hendy had a used 90L tank for sale recently, and he's located in the northeast, so you might want to drop him a line.

Worst case you can install a standard 70L tank for now, if you can't find a 90L tank, and swap it out later if you can find a 90L.

BTW, welcome to the forum!

 

[Jlaa]

Hello fellow 500e fans .
I recently purchased a 500e from a member in Toronto.
I've been enjoying the car until the dreded gas smell in car and trunk .
So I'm looking for a good gas tank .
Any info or or leads would be appreciated
Adam

Welcome! I love the prefacelift look of your car. Btw - your issue might not be the fuel tank. You might wantnto start with least invasive approaches first. See here about the check valve - Fuel Lines & System Maintenance | M119 Engine

 

[gsxr]

Oh yeah - I was assuming the source of the odor had been confirmed to be the tank. If not, do that first. The tank vent valve should be replaced if original, and absolutely replaced if the old tank is verified to have partly collapsed.

Either way, inspect all the fuel hoses at the rear of the car, click here for details / photos / part numbers. The high-pressure hose exiting the fuel filter is a very common leak point, and extreme fire hazard if it leaks... more than one 124 has burned to the ground due to this. If the tank comes out just replace everything... feed hose from tank to pump, new OE hose from filter to chassis hard pipe, two new Bosch pumps if they are original, tank vent valve, and the short hoses around the vent valve.

 

[captruff]

i might have one...ill need to verify


Jeff

 

[500e702u]

I took the back seats out and the trunk interior . It seems to be pooling to the right side, below of the tank. I jacked the car up and removed the cover to the pumps and it's completely dry ..also checked the tank vent from below the car again dry.
I sprayed brake clean and cleaned it up..changed the gas cap and took it for a ride ...a left hand turn and checked it ..fresh gas again . I noticed the gas in the rear right behind the seat ..it seems it's Leaked through one of the factory small holes .
I'm thinking the leak is coming from the from of the tank ..where I can't see.

 

[500e702u]

Thanks guys for the welcome. This is my 5th 500e I've owned over the last 20+years and always regretted selling them ...this one's going nowhere!!!

 

[gsxr]

If there is no leak at the filler cap, or the sending unit... yeah... sounds like a hairline crack in the tank. When removed you may find it partially collapsed, which is more common than it should be. I think @Rain went through this last year.

5th 500E... niiiice!

 

[500e702u]

Looks like she's going into my garage until I fix her ...not taking any chances on it catching fire ..I already drive it a week like this .

 

[Rain]

If there is no leak at the filler cap, or the sending unit... yeah... sounds like a hairline crack in the tank. When removed you may find it partially collapsed, which is more common than it should be. I think @Rain went through this last year.

5th 500E... niiiice!

500e702u, based on what you’re describing thus far, it does sound like it might be an issue with a partially collapsing tank. Hopefully not? But there’s honestly only one way to find out: removing the tank for an inspection. Before that, though, you could also have a smoke test done to see if there are any leaks or pressure inconsistencies. I had my Master Tech do that for me, and while nothing turned up initially, a week later we removed the tank and found the entire backside to be collapsed. And yes, if you’re wondering, that sort of thing is pretty much impossible to repair.

The most common cause for a collapse, or preliminary hairline fractures, is a clogged vent valve. It’s a small white plastic little thing that costs pretty much nothing, but has the potential to ruin an entire tank if not cleaned regularly, or, more responsibly, just replaced. It’s beyond strange(and disappointing) that Mercedes didn’t address that issue during initial testing of the 500, because the issue seems to be directly related to the tank and vent valve being originally designed to handle the pressure generated from a smaller engine—not necessarily the monster V8 that got dropped in. Or at least, that’s what a few of the Master Techs at Fletcher Jones concluded after a long study of my situation.

So, yes, as gsxr already noted, you 100% need to replace the vent valve. It should honestly be at the top of any list of mandatory maintenance for our cars. Why? Because you can’t buy the original 90L tanks new from MB anymore. They unfortunately confirmed with me last year that they sent me the last one. And because it’s illegal in most(all?) states to ship used tanks, the only way to replace a tank with a used one is to find someone(preferably here) that you can trust, and has one available, is within driving distance, and is willing to part with it. Or, as was already mentioned, you can easily put in the smaller 70L tank without any problems—at least until you track down a 90L one.

gsxr had also suggested to me that I go ahead and inspect and replace all sorts of other fuel-related pieces while I was in deep and had the tank out—an excellent idea that ended up giving me peace of mind when trying to get rid of the lingering fuel smell after it was all over. The simplest, cheapest thing to replace: the O rings on the tank! Especially the ones for the fuel sender. Those rings age and thin over time(especially 30 years later). When worn out, the slightest turn while driving can lead to fuel leaking out of there. Even the smallest drop can yield a very strong fuel smell in the trunk and cabin, and you won’t even necessarily see a puddle under the tank.

If you’re curious, in addition to installing a brand new tank, and new vent valve, I also went and changed all the fuel lines, breather line, purge valve, charcoal canister, fuel pumps, and gas cap. Also, I removed all of the trunk lining, rear seat, and floor carpet, and deep cleaned every inch. Hopefully you don’t have to go to those lengths, ha. Best of luck to ya!

 

[Jlaa]

500e702u, based on what you’re describing thus far, it does sound like it might be an issue with a partially collapsing tank. Hopefully not? But there’s honestly only one way to find out: removing the tank for an inspection. Before that, though, you could also have a smoke test done to see if there are any leaks or pressure inconsistencies. I had my Master Tech do that for me, and while nothing turned up initially, a week later we removed the tank and found the entire backside to be collapsed. And yes, if you’re wondering, that sort of thing is pretty much impossible to repair.

The most common cause for a collapse, or preliminary hairline fractures, is a clogged vent valve. It’s a small white plastic little thing that costs pretty much nothing, but has the potential to ruin an entire tank if not cleaned regularly, or, more responsibly, just replaced. It’s beyond strange(and disappointing) that Mercedes didn’t address that issue during initial testing of the 500, because the issue seems to be directly related to the tank and vent valve being originally designed to handle the pressure generated from a smaller engine—not necessarily the monster V8 that got dropped in. Or at least, that’s what a few of the Master Techs at Fletcher Jones concluded after a long study of my situation.

So, yes, as gsxr already noted, you 100% need to replace the vent valve. It should honestly be at the top of any list of mandatory maintenance for our cars. Why? Because you can’t buy the original 90L tanks new from MB anymore. They unfortunately confirmed with me last year that they sent me the last one. And because it’s illegal in most(all?) states to ship used tanks, the only way to replace a tank with a used one is to find someone(preferably here) that you can trust, and has one available, is within driving distance, and is willing to part with it. Or, as was already mentioned, you can easily put in the smaller 70L tank without any problems—at least until you track down a 90L one.

gsxr had also suggested to me that I go ahead and inspect and replace all sorts of other fuel-related pieces while I was in deep and had the tank out—an excellent idea that ended up giving me peace of mind when trying to get rid of the lingering fuel smell after it was all over. The simplest, cheapest thing to replace: the O rings on the tank! Especially the ones for the fuel sender. Those rings age and thin over time(especially 30 years later). When worn out, the slightest turn while driving can lead to fuel leaking out of there. Even the smallest drop can yield a very strong fuel smell in the trunk and cabin, and you won’t even necessarily see a puddle under the tank.

If you’re curious, in addition to installing a brand new tank, and new vent valve, I also went and changed all the fuel lines, breather line, purge valve, charcoal canister, fuel pumps, and gas cap. Also, I removed all of the trunk lining, rear seat, and floor carpet, and deep cleaned every inch. Hopefully you don’t have to go to those lengths, ha. Best of luck to ya!

@Rain @500e702u —

You may already have a good list / more experience than I at replacing fuel system components…. i found it helpful to diagram everything out when I recently addressed my car’s fuel system. Maybe these diagrams will help others in the future. OWNER - OWNER - jlaa | Owners and Their Cars