gas tank leak

[Pete R]

When I FILL my tank I get a strong smell of gas in the car that seems to originate inside the right rear wheel well. If I use a few gallons the smell goes away. I assume one of my hoses at the top of the tank is old, cracked and leaking. I plan on dropping the tank once I use up this tank. My question is do I need that charcoal canister(in the r front fender well). It seems to be an emissions thing. Can I just plug those outlets off at the tank? Other wise I'll have to run new lines, which I'd rather not do if it don't need to. I have Euro CIS injection if that matters

[MPDano]

Originally Posted by Pete R

When I FILL my tank I get a strong smell of gas in the car that seems to originate inside the right rear wheel well. If I use a few gallons the smell goes away. I assume one of my hoses at the top of the tank is old, cracked and leaking. I plan on dropping the tank once I use up this tank. My question is do I need that charcoal canister(in the r front fender well). It seems to be an emissions thing. Can I just plug those outlets off at the tank? Other wise I'll have to run new lines, which I'd rather not do if it don't need to. I have Euro CIS injection if that matters

We have the same issue which I haven't pin-pointed yet. I now just fill up to the 3/4 mark on the gauge. Once I get time, I will investigate. Let me know what you find out.

[riber.bentsen]

Could be ventilation hose that protrudes the inner fender wall, could be hose to expansion tank, or it could be the in-tank fuel level sender seal.

The symptoms you discribe sound like the last may be your problem. There is a write-up on how to change it here:

88 Fuel Sender Seal Replacement w/pics

[Landseer]

Or like mine, could be holes from screws to install stereo equipment. The tank butts up against the underside of the hatch floor.

[Landseer]

Here's some

[Pete R]

I'm sure all that stuff is original so I'll just probably end up redoing all the soft lines and seals. Does anyone know if I need the charcoal canister though? I'd like to just seal those off at the tank if I could. How long does it take to get the tank on the ground?

[MPDano]

Not sure about the Charcoal Tank, but if you have Smog Inspections, I suggest not to remove it.

Here's a Diagram of the parts so this will give you an idea of the all the hoses, etc. you'll be changing out.

As far as time to drop, I would say about an hour. Put a hydraulic jack underneath to support the tank for dropping and installing. The strap bolts were the biggest pain for me. Also, theres a bolt where the Tank Filler is.

[Pete R]

great, i'm very suspect of hose 11 judging by the origin of the smell, but we'll see. I have no emmisions testing in NH. Well, it's just a visual at this point, and no one knows what to look for anyhow. I just have to burn most of a tank off gas now.

[MPDano]

Originally Posted by Pete R

great, i'm very suspect of hose 11 judging by the origin of the smell, but we'll see. I have no emmisions testing in NH. Well, it's just a visual at this point, and no one knows what to look for anyhow. I just have to burn most of a tank off gas now.

Funny, I was thinking that hose too. Also, maybe open up the circular cap to expose the Fuel Sender and see if you can see any signs there, might save you a trip of downing the tank. I was thinking of my Fuel Senders Rubber Gasket might have failed too. Keep us posted.

[84Shark]

You are in good company, my 84 has the exact same "fill up and leak" symptoms...

Dwayne did a nice write up on this, in his case he had an actual crack in the tank... I hope our issue is just a cracked hose...

[Landseer]

Pete,
You might want to replace the lines and keep the unit.

I've had two cars from new england that had rusted-through metal air lines under the car.

Went to NAPA and bought a few 4 or 5 foot lengths of metal gasline and replaced them. Connected to the good stuff using fuel injection hose.

I'm trying to keep the emissions stuff because when I was contempating a move to NJ a few months ago I discovered they are strategically reinforcing their scrutiny of older cars and I think its going to be a trend. The presentation I saw vividly made the point, true or false, that the lions share of emissions was from poorly operating cars several years old, and especially early stuff that other states have exempted. So they give you a very limited registration as a historic/antique or basically force you to meet standards for your year. Depending on politics, federal emissions law enforcement may cease to be optional in more states as the effort expands (speculatively) to force the old stuff off the road. So, it might be worth maintaining these simple systems. Just a thought.

[MPDano]

Hey Landseer,

So in your case of pinholes, what will you do about those?

[MPDano]

Also, plan on getting some sort of Rubber Weatherstripping for the Tank Strap since it's most likely will fall to pieces when you drop the tank. I got some stuff from Homet Depot when I put my Tank back in.

Porsche 928 Forums dot com - View topic - Pics of my First 928 and Current Project

[Landseer]

Originally Posted by MPDano

Hey Landseer,

So in your case of pinholes, what will you do about those?

Plastic welding. MAYBE ---edit -- research is not looking promising on this.
Epoxy failed.

I also lucked into a spare tank a while back from an 89 S4 being parted.
Got tank for $100 and trans, converter, TT and cables for $150.

Mission is to swap tanks, then fix the leaker.

[Pete R]

The reason I keep mentioning the charcoal canstister is, well, because mine is already missing. Just two hoses that end by my washer res. In 20 years I never had a reason to look for it before until the smell (not coming from there btw), maybe I'll find a used one and just thow it in.

[MPDano]

Originally Posted by Pete R

The reason I keep mentioning the charcoal canstister is, well, because mine is already missing. Just two hoses that end by my washer res. In 20 years I never had a reason to look for it before until the smell (not coming from there btw), maybe I'll find a used one and just thow it in.

Yeah, good idea. 928 Intl.

[AaronCross]

Figured I would add on to this thread instead of starting a new..

I've got some good shots of underneath I'll put up as soon as i get them uploaded but my main question is:

Would you replace or rework this strap? What materials or what would be the best
way to rebuild such a thing?






Thanks!

[Mrmerlin]

replace all of the those parts then you wont have an issue in a year

[AaronCross]

$123 and a 3 week wait from germany to get this hose(928.356.053.01).. (928 international & 928 specialists)

Any ideas on a better/quicker buy? Would you try fabricating this hose yourself?

[JhwShark]

You could take the hose to an AC shop or other shops (call around) and have them make it for you possibly using some of the original fasteners (if good) and new high pressure fuel hose. Some here have had made other hoses, not sure if this one...Check with Roger if he has them??