E30 Fuel Leak

[CanadianDirty30]

Good to hear! Glad I found it quick enough. I hope they'll have the part haha need the car back on the road today or tomorrow

[Dave_G]

Okay guys last update! I decided to drive my car around my drive with the cover off the backseat and saw that it overflows from the top, around the fuel pump when I move and the as splashes! Leak located, I think it would just be the o-ring around the pump that needs replacing them I'm assuming

I hope for your sake the o-ring fixes it. My previous E30 had that same leak on the top of the tank. It pooled around the fuel pump, which made me also think it was the o-rings (I also replaced the one on the other side for the fuel level sensor), but in my case that did not fix it.

I hope it works for you, but if it doesn't, and if you live in the rust belt, my bet is going to be on the horizontal vent line that runs across the top of the fuel tank. It's between the two access panels, and you can't see it unless you pull the tank out. Salt collects on the top of the tank and rusts out that vent line, and fuel leaks out and pools around the top of the fuel pump, the fuel level sensor, or both. The only fix is either a) replace the tank; or b) never fill the tank above 2/3.

When I pulled my tank out, there was a gaping hole in that vent line. My current E30 had the same thing happen, but lucky for me, the tank was replaced by the P.O. As was mentioned earlier, it's not a difficult job, but it's a PITA, because you have to remove the exhaust and the drive shaft to drop the tank.

[Cephas]

Thats where the one on our race car leaked as well. Job takes time because you have to drop lots of stuff. But it's not terrible. Replace all rubber lines and fuel filter too. Those premolded ones have to be ordered.

Hopefully you get lucky and its the o-ring, but judging by the rust I see around that tank, it's not looking good.

[CanadianDirty30]

I hope for your sake the o-ring fixes it. My previous E30 had that same leak on the top of the tank. It pooled around the fuel pump, which made me also think it was the o-rings (I also replaced the one on the other side for the fuel level sensor), but in my case that did not fix it.

I hope it works for you, but if it doesn't, and if you live in the rust belt, my bet is going to be on the horizontal vent line that runs across the top of the fuel tank. It's between the two access panels, and you can't see it unless you pull the tank out. Salt collects on the top of the tank and rusts out that vent line, and fuel leaks out and pools around the top of the fuel pump, the fuel level sensor, or both. The only fix is either a) replace the tank; or b) never fill the tank above 2/3.

When I pulled my tank out, there was a gaping hole in that vent line. My current E30 had the same thing happen, but lucky for me, the tank was replaced by the P.O. As was mentioned earlier, it's not a difficult job, but it's a PITA, because you have to remove the exhaust and the drive shaft to drop the tank.

Oh okay at least I know another thing to look out for now! I'm gonna replace the o ring tomorrow and if it doesn't help i may have to drop everything out by the sounds of it. I'll see how it goes. Thanks for the advice!

[CanadianDirty30]

Thats where the one on our race car leaked as well. Job takes time because you have to drop lots of stuff. But it's not terrible. Replace all rubber lines and fuel filter too. Those premolded ones have to be ordered.

Hopefully you get lucky and its the o-ring, but judging by the rust I see around that tank, it's not looking good.

Yea I'll admit it doesn't look to pretty. I'm crossing my fingers that the o ring will solve my problem! If it doesn't, I'll deal with it and drop everything out. Wish me luck haha

[CanadianDirty30]

So it turns out it's not the fuel pump o ring, the fuels actually coming out around the edges of the fuel level sender unit which attaches to the top of the pump. I can't find any information on this, is there supposed to be a gasket there? Or do I need another unit which is like 200 bucks

[TobyB]

There's a molded rubber seal- funny, it kinda looked like that on your pic, but they don't usually leak...
I kind of remember it being molded TO the fuel level sender, but that seems odd.

You could ghetto something with fuel resistant rubber, or find a used one- the tank
sender's not bulletproof, but it's pretty durable.
Heck, the fuel- resistant RTV in quantity would probably work just fine.

hth
t

[CanadianDirty30]

There's a molded rubber seal- funny, it kinda looked like that on your pic, but they don't usually leak...
I kind of remember it being molded TO the fuel level sender, but that seems odd.

You could ghetto something with fuel resistant rubber, or find a used one- the tank
sender's not bulletproof, but it's pretty durable.
Heck, the fuel- resistant RTV in quantity would probably work just fine.

hth
t

Thank you! I just wasn't sure if there was supposed to be a gasket there or not. Thanks for the help! I'm sure I'll figure out what material to use

[Rob Daman]

do you guys think the o ring is the fix for my leak?