Gasoline in Trunk

[gte619n]

Fellas,

I've got a bit of a head scratcher. Had a relatively drama free trip up to SESF and then continued up to North Carolina through the twisties in the mountains. I filled up in Braselton and everything was fine. Right before I made the turn up on to 64, I started to smell fuel in the trunk. It got stronger and stronger. Once I arrived at my destination I pulled everything apart in the trunk and the panels (and my suitcase!) were saturated with gasoline! Not good.

So, I checked all the standard places. PO had some very creative "fixes" for the fuel situation. The three evap hoses all went into an empty plastic tank behind the battery. This tank had been cut in half and "sealed" with a piece of MDF. Non-fuel safe silicon was used to close up the chopped up half, so that was completely gone. The suction hose routed to the front of the car and dumped into the crossover tube.

The fuel sender access panel in the trunk does not have a gasket. No rust in the evap hard lines by the fuel filler. It looks like the steam has a small leak, so I need to get that taken care of, but it's not emergent. I tried to recreate the issue on Sunday but could not get a drop of gasoline into the trunk. What could have happened? Any ideas?

As I redo the tank and re-gasket everything, I was wondering if I could just cap off the evap lines and get a vented gas cap? What about taking the three lines and routing them into a small charcoal canister in the trunk? I'd like to get rid of that vacuum lines going to the front of the car. Also, there looks to be a small plastic tank in the bottom of the fender with a line going to it. What is that guy for?

Appreciate any insight. Thanks!

[dwcains]

My '85 (not an M-car) is a Euro, so it never had all that evap plumbing and charcoal canister from the factory, and your car shouldn't have, either. I'd have a look at realoem and put the car back to its original configuration. There will still be that plastic tank in the trunk, but basically the vapors are vented to the atmosphere. No need for any lines going to the front of the car. I don't think you should eliminate that expansion tank and seal the lines because there won't be any room for fuel expansion, and I'm not sure you can run a vented cap. I am careful not to overfill my car's tank, as if I do fill it to the brim, there will be some leakage as the fuel gets warm and expands, so I just fill it until the gas pump clicks off the first time.

Mine did have a charcoal canister installed during Federalization, but it was merely screwed to the inside of the right front fender, and never hooked up to anything. Does yours look like this:

[gte619n]

Is it possible that a non trivial amount of gasoline could have crept up through the evap lines into the trunk?

[slofut]

Is it possible that a non trivial amount of gasoline could have crept up through the evap lines into the trunk?

Yes! And with the bubba evap modifications it's probable. Like Dean says, it would be easier to put it back original. Parts like the evap tank under the rear glass would be easy to find used. System works well as designed. Only problem I had ended up being the three original vapor lines from the tank, I don't care if they look new, replace all three and it'll prob take care of the fuel odor that Bubba was trying to fix the first time.

[gte619n]

When I check out RealOEM and look at the M635CSi fuel expansion tank, I see this diagram. When I search for that part number, I find this part, which is the tank that I have, or, rather, 1/2 of the tank that I have.

Should the pictured tank at ECS be the part that I need? I assume that the other port should vent outside the car?

[dwcains]

Yes, I think you'd be good with that, and venting out to atmosphere with that single hose. If you want an OEM look, I was able to find some of the cloth braided hose at a VW dealer several years ago, and recently used what I had left on my E24. You might see if ECS also has it, and I've even seen it on eBay and Amazon.

[slofut]

Dean that charcoal canister looks nothing like the US factory version. :)

[dwcains]

You see some odd things on the Euro cars sometimes. Mine didn't get the ugly side markers added on, nor the cats and O2 sensor, but it did have all the gauges and OBC changed and signals added to the front corner lights. I just recently found a German gauge cluster and OBC, so it's now just about the way it left the factory. After I trashed that Purolator charcoal canister, I saw one on eBay for $80 - apparently the 911 restoration guys like them.

[slofut]

I'd just about give my left nut for a euro 635 , I'd rather have it than an M.
Here's a pic of the U.S. can...

Untitled by Bill Smith, on Flickr

Untitled by Bill Smith, on Flickr

[GRNSHRK]

Gents, the one in Dean's photo is actually the factory stock US version series I charcoal vapor canister

Here's a shot of mine, 1980 vintage, showing the exact same model type

But I doubt that this is related to the problem with gasoline in the boot, however

Think I would go with the previous advice, tracing back all of the lines including those for fuel vapor returns

[gte619n]

Just to verify, are these evap hoses the standard 8mm fuel hose? Thanks!

[dwcains]

Hmmm, I thought it was 6mm ID.

[gte619n]

Ah great. For a second there I thought I was going to just be able to use something I had!

[dwcains]

Check realoem using your VIN to be sure. Just checked mine, and it does confirm 6mm ID hose for the vapor lines.

[slofut]

Gents, the one in Dean's photo is actually the factory stock US version series I charcoal vapor canister

Here's a shot of mine, 1980 vintage, showing the exact same model type

But I doubt that this is related to the problem with gasoline in the boot, however

Think I would go with the previous advice, tracing back all of the lines including those for fuel vapor returns

Once again I stand corrected . Mine is an '88, didn't check the '87 but the early cars are obviously different that the late ones.