plambert

Just be careful when reinstalling the fuel sending unit.

Earlier this summer, I was very low on fuel (close to home) so thought I'd have a look at the bottom of the tank to see if there was any sludge in there that would need to be cleaned out (100k miles). Bottom of tank looked fine. Reinstalled the fuel level sending unit (a bit too hastily, it turned out) and proceeded to get fuel on my way to a haircut appointment.

Thought I smelled a little bit of fuel in the next mile. Smelled more on the way home, so pulled over to have a look. Just about $hit my pants! The rubber o-ring had broken (or, I should say, I broke the rubber o-ring) and fuel was running out from my now-full tank into the bottom of the frunk. Used a bunch of paper towels to clean it up. Towed it home and removed everything--battery, spare, etc.--for a full mop-up & clean-up with Simple Green, lots of water rinse (helps to remove the plugs in the basin of the frunk, as the water will drain more quickly), air dry (mercifully, it was a dry, sunny, breezy day).

Scored an o-ring locally, squirted it liberally with silicone spray, and ever-so-gently rolled it up the neck of the tube. all is now good.

Metal Guru

You might want to check that o-ring to make sure it hasn't turned to mush if your not sure of it's pedigree. Not all grades of rubber can withstand gas and vapor.
As for stock sizes for straight replacement hose, 3/8" O.D. fuel hose from Summit Racing will work for the two rollover valve lines. For the lines from the fuel tank to the expansion tank, 3/4 " O.D. oil line from Bat Inc. works well.

SuperUser

Thanks Guru!

FeralComprehension

FWIW, the sender o-ring part number is 999 707 115 40, indicated size 44x4. Pelican gets $1 for it.

plambert

Paul,
You make an excellent point. The ring I purchased was for use w/fuel lines. Would NOT recommend buying just any ring that fits!

Sea964

Am I just too tolerant?

My trunk smells, and so do most 964's and 993's I've seen. I've sort of thought, "they all smell like that".... I went camping a couple of weekends ago, my sleeping back (among other things) in the trunk. When I pulled out the bag it had a bit of gaseous odor but by bedtime, it had aired out and didn't smell.

Metal Guru

I will admit to initially replacing my rubber with stock sourced from the local auto parts store labeled "emission hose". Within a week it was slimy from vapor attack. That's when I got hold of Bat Inc to get stock rated oil/fuel. Same with the Summit Racing stock; it is fuel line. Hate to see anyone repeat that mistake.

Vandit

Hey guys, after reinstalling the tank after an evaporator replacement, I am getting a bunch of fuel smell when the tank is topped off and I'm taking hard right turns.

Whenever there is a smell, I can feel it is damp where the two hoses meet up with the fuel filler neck. I've tightened the clamps on those two hoses and it persists.

What's the appropriate course of action? Fuel filler neck replacement? I see lots of part #s for the same piece. What's the correct part for my '91 coupe? Anything else I need to replace while I'm doing this job?

540964

At first I replaced the cap seal but continued to smell fuel. Then I replaced the fuel filler neck and the smell went away completely. I never could find a crack.

Also, it isn't difficult to fill the tank anymore. Before replacing the neck, the fuel nozzle would shut off many times while filling the tank. Now I can fill the tank quickly without the nozzle cutting off again and again.

LPMM

Staying tuned for some ideas, I too get the smell and I have no idea where it is coming from.

machisono

Vandit,
Part # 964-201-043-07 from Sunset Imports (coming from Germany) for $153.26 + Freight. Purchased this past June and it really helped for my 91 Cab. For $3.96 I added gas cap gasket too.

Hope this helps

Goughary

Vandit...I have the same issue and have been putting it off so long that the fumes from the gas have melted and bubbled the rubber seals where my fenders meet the cowling and my almost brand new wind shield seam...not to mention my daughter gets pissed that she has to sit in the car when we first get in, Cuz "it stinks in here"...

So as these threads keep coming back around, I get re motivated to buy the correct parts and get to it...let's see if it sticks this time...

tfitch03

I changed the fuel filler neck and the fuel smell is completely gone in the cabin. My trunk still stinks though. I am hoping the carpet is just saturated and will go away with time. Getting the smell out of the cabin was a big enough win for me though. I too ordered from Sunset.

2000m2

Thinking I may need to attack this project next. The fuel smell is pretty strong in the cabin. I leave the windows open when parked at home in the garage. I replaced the fuel cap seal, but that didn't help anything. I do notice that the smell is stronger when the tank is full, not sure if that points to any particular part of the fuel system though.
Looking at this write-up to change out the filler neck:
https://rennlist.com/forums/964-1989...placement.html
Everything appears original in my 1990 964 with ~114k miles, but I'm not seeing any leaks or cracks anywhere.
Does the fuel filler neck make sense as the next item to replace here?

540964

Check the fuel pump connections. I once found a leak at the banjo fitting.