Fuel vent line hoses/fuel smell inside car!!!

[rsefczek]

now i'm thoroughly confused. i pulled the diagram from my opel repair manual and it shows the gt as having a top, near center vent line between the filler pipe and the fuel sensor. but the .jpg from ealier in this thread doesn't show anything like that. i looked at my set up again and there is no center vent nor can i find a vent to the charcoal cannister. looking at the jpg it looks like one of the tee fittings goes out to the cannister but, since i'm lacking that fitting, i don't have that line. my thoughts are:
1. put in another tee fitting and connect according to the .jpg
2. run a line from that out to the cannister (assuming i can find that!)
the line to the cannister may be a long one, correct? where does the vent line leave the body? since it is currently non-existent, i don't know where it goes and the diagram isn't too helpful. crawling under the car i can see where the fuel line exits and there may be another opening further to the rear of that. is that the vent line opening?
are the manual diagrams often wrong?

bob

[yellaopelgt]

Its been a few years since Ive done my vent lines but... not all GT's have a canister... if you did it would be up in the nose by the battery.I think...mine did not have one so...and its a early 1970.I re-did mine with fuel line and worm gear clamps and it took me about 2 hours. BTW...the FSM was no help whatso-ever and luckily my old cracked lines were still in place. It cleared up the gas smell immediatly,thank god!!! That was terrible. I'm taking a stab in the dark but memory tells me it was 16-18 feet of line to repair.
Joe

[jvandyke]

I had a chance to look under my leaking tank, I pulled a tail light too. Very strange no wetness by the vent line on the left/driver's side as I suspected as I just fueled up and jacked the right front for caliper repair, thus pushing the gas to the left side of tank, that's where I thought I'd see leakage, the vent line in gas due to tilt.
But dry. bottom of car is soaked in extreme driver's rear corner, dripping into a puddle (now just a wet spot).
Maybe filler tube is getting gas contact where it normally wouldn't (due to raised front) causing an actual fluid leak and that filler tube leak was the source of my fumagation after filling up too. Sound plausible?

I work too much. Spend hours at "work" mentally imagining problems and fixes to problems that would probably take minutes to investigate and solve if I actually had the car.
Solution: quit my job and pay myself to fix my car

[namba209 (R.I.P.)]

Bob, charcoal cannisters are available at your local auto parts store. I got one for Willit? because I needed it for the computer system on the car. Here's some pics of where it is supposed to be mounted, and where the vent line comes out by the fuel feed line. I ran my electrical fuel pump lead through that hole and put a couple more in behind that for my fuel return and vent lines. I had to modify the attaching bracket/clamp on my new cannister, it was a bit larger than the original, I just cut it in half and used it like a clamp to hold the new can in place. HTH.

[markandson]

Another bad possibility is that you have a hole in the tank where the outlet is. The original fitting is brazed in, so you have dissimiliar metals in the area which causes a little galvanic action. When I did my tank I had to cut the area out and put in a patch. You can see it in the thread I referred to earlier in this thread. If you have a hole, the only way to fix it is to remove the tank.....big job.

[rsefczek]

thanks for the pics, ron, it really helped. looks like the p.o. removed the cannister and clamp since they do not exist where your picture shows 'em. i guess it's time for a trip to the auto parts store for a cannister and some kind of clamping arrangement. nothing like spending a little more money....

bob

[namba209 (R.I.P.)]

thanks for the pics, ron, it really helped. looks like the p.o. removed the cannister and clamp since they do not exist where your picture shows 'em. i guess it's time for a trip to the auto parts store for a cannister and some kind of clamping arrangement. nothing like spending a little more money....

bob

Bob, a quick and dirty method to mount it, would be to fab up a bracket, you can use sheetmetal screws to hold it horizontally to the front structure, then run a large hose clamp or two under the bracket, and around the cannister. Until I found and modified the original clamp, that's what I was contemplating doing.

[jvandyke]

can't pin down the source of the leak sure is leaking, not done with brakes but lowered car back down to hopefully stem the flow as it really reeks in the garage, not good

Replaced all stock vent lines (which didn't look bad) with 5/16" fuel line. It was a pain fishing the line through the floor under the tank and back up to vent T. In the end I ground down the outside of the 5/16 line (about a foot's worth, so diameter was less) on my grinder wheel shoved it down from the top (with my hand through the brake light opening) and watched the hole under the car, saw the end through the hole, grabbed with a needle hose and hauled some through. No canister up front on mine so at the moment it's open to the air by the pumpkin (previously it was cut off right where it came out of the car by the fuel line).
There was one piece of hose spliced on the plastic line from filler neck, must have broken there in the past. This seemed a bit damp.
Gas actually poured out of the passenger side vent hose when I pulled it off the tank.
I guess if you really fill this tank up, you fill up the vent lines too, as you can fill the filler neck, you could have gas in the vent lines quite high (probably why the lines are clipped to the roof of the compartment, to keep them high.
I hope that solves my gas smell. Hard to tell, too much has been soaked and seeped for the last few days. How long before that dissipates I wonder?

[Mike Preble]

Light a match. That will help get rid of it. HAHAHA

Mike

[OriginalOpelGTOwner]

I replaced my fuel tank vent hoses last spring with 5/16 ID fuel line. To route line through hole in the floor pan there is a clearance depression in the crossmember located just inboard of the left side market lamp for the vent line. Did you try routing the line pass the crossmember at the depression?

[jvandyke]

I replaced my fuel tank vent hoses last spring with 5/16 ID fuel line. To route line through hole in the floor pan there is a clearance depression in the crossmember located just inboard of the left side market lamp for the vent line. Did you try routing the line pass the crossmember at the depression?

I routed it just like OEM (unless someone preceded me in this, which I doubt), which was down right in front of the driver's side brake light, under the tank then out a hole right near where the fuel line to carb is located. The hole through the chassis is too small for this tube (as has been said before). (Enlarging it scared me, anything sparky with all those fumes floating around is kinda scary)
(I think the diagram shows slightly different set up in '73)
Anyway, I got it down. What I'm going to do with the "loose end" under the car I don't know. PO had it just sitting there too. I sure hope this solves my gassyness (the burritos don't help either).

PS had to search to find that the nuts to release the tire/jack bracket that sits on the shelf on passenger side (has to come out to get shelf out) were in the rear wheel well, above the tire, on the outside of the car (for the benefit of those that are doing this in the future) the heads for these bolts are smooth like rivets.

[Crazy Harry]

I replaced my vent lines with fuel line as well. I didn't have to remove the tire bracket mount on the passenger to get the shelf out.

The gas smell is significantly less now, but not completely gone. Any other suggestions Does one have to change any other components back there, like the rubber section between the tank and the filler neck or a fuel level sending unit seal? I think my charcoal canister in the front has a leak, looks like rust got to it, would that make a difference?

Thanks,
Harold.

[OpelJim]

Yep, I've read up on this and downloaded the diagrams and all that, 5/16" fuel line, clamps. Don't recall about how many feet it takes now, anyone remember? Also, at some point to get through the body 5/16 was tight, maybe splice a little section of someting a bit narrow there? I have to go look through all my stuff again. I suspect as soon as I lower the car I'm okay for the moment. Probably pouring out the top left line, gas is way too expensive for this loss!

http://clubs.hemmings.com/clubsites/...h/TankVent.pdf

from another thread

I read Charles Goin's repair information and it is very good advise with the exception of the "5/16 th Tees" you can use from a local hardware store

The one "Tee" off the filler neck has a small pin hole opening on one side and a larger hole on the other.
There is a design reason that small hole has to be mounted towards the neck This is to lessen the amount of gas that will flow down the line when filling the tank, and lessen the vapors that go into the compartment.
If anyone wants the tech tip from Jim Petzold with instructions on how to do the repair and an easy to understand illustration too I can send them copies.

[rsefczek]

i could definitely use that explanation, jim. p.m. or personal email?

bob

[BDD]

I need that tech. sheet and explanation too.

The info. that I have shows the small opening in the tee valve, NOT in the line to the filler cap but in the tee at the line thta goes to the charcoal canister to reduce chance of gas going that way.

What size does this opening have to be? Only vapor moves through it.

Can any old tee be used, just put a press fit metal tube in that end of the tee to limit that particular orifice size?

[Anonymous D]

"Does one have to change any other components back there, like the rubber section between the tank and the filler neck or a fuel level sending unit seal? I think my charcoal canister in the front has a leak, looks like rust got to it, would that make a difference?"

In answer to your questions:

(1) Yes, there are other components involved, and it's a good idea in general, to just go ahead and replace the wide hose between the tank and filler neck tube, and to also replace the gas tank sender gasket, at the same time as you have done the labor to access the hoses off the fuel tank. I have experienced an ongoing fuel smell, even after replacing the vent hoses and clamping them off, which wasn't stopped until I took those extra steps. In many cases, these are 34-38 year-old original components that are asked to prevent a possible explosion! Certainly it's worth an extra $20 for the parts, to eliminate that scenario.

(2) It's a good idea to also connect the carbon cannister line to the tank. It helps to reduce tank pressure buildup, by providing a filtered outlet for fumes to be vented out. (Also understand, that when you rely on a tech tip, that you need to verify that the writer has actually performed the procedure and has monitored its longer term results on an actual GT. Badly written tips, which have been observed in the past, can invite complications and even injury. Variables can also include profit motives, publication deadlines, the degree (or lack) of social responsibility of the writer, and individual ego).

[carter840]

Well I want to drain my fuel tank but i can't seem to unscrew the plug in the bottom of the tank i have tried all types of sprays to loosen it but nothing has worked. Can anyone suggest another way to drain the tank i have 8 year old gas in there now that i want to get rid of. Also i noticed as well that the vent lines on the tank have fallen apart can someone recomend a good replacement hos that will work as a recplacement?

[namba209 (R.I.P.)]

You can drain the tank by removing the fuel line where it attaches to the metal tube coming out of the tank. I would put a short piece of hose over the metal tube, so you can squeeze it closed or plug it to stop the fuel running out if needed. The replacment vent line hose has been discused numerous times on the site, do a search for fuel tank vent lines and you'll find a lot of posts on it, also make sure you put the "T" fitting back in the correct position when you replace the lines, there are different size holes in them for a reason. HTH.

[West Coast GT]

I've found no good way to dispose of old fuel once it's drained from a fuel tank. The 3 times I've had this issue, I've left it in the tank and followed the following procedure;

1. I install one of those semitransparent white plastic cheap fuel filters in the easiest accessible location (under the back of the car)
2. Top the fuel tank off with good fuel,
3. Add a can of fuel additive to absorb the moisture,
4. And burn the fuel through the engine.
5. Change the cheap filter when it appears clogged.
6. Add more good fuel as needed to further dilute the bad fuel.

I change the cheap filter and leave it on for a tank or two just to make sure I've captured all the crud. Then remove the filter and trust your real filter to do its job.

No Muss, No Fuss.

[George]

Do you have to take the tire shelf out to see the holes in the tee or can I go in through the taillights?I just replaced all the vent hose and didn't know the tee had two different size holes.