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MG TD TF 1500 - Petro Leaks, Tank Fill Neck

Does anyone have a good solution to fuel leaking from the tank fill neck when the tank is full? I have a metal rod 'drip stick' with a round baffle on top that fits in the fill neck under the gas cap. It is supposed to slow the fuel sloshing and spilling but it doesn't work all that great. I have no problem so long as I do not fill the tank. However, if I do come close to filling the tank I lose fuel from the top of the fill neck. I have replaced the cork seal but this hasn't helped at all. I have also tried cutting a piece of gasket material to fit the fill neck and punched a vent hole slightly off center so the material sits tightly on top of the 'baffle/drip rod' but I found that this doesn't work either. The gasket just gets soaked with fuel (tank full) and fuel still spills out the neck.
I might tryp cutting a new seal but this time use a material that will not soak with fuel.
Does anyone have any ideas? I am not concerned about cleaning up the fuel spill on the tank so much as I am worried about ruining the paint.
LD Kanaster

LD,

Do a search of the archives for fuel leaks from the filler cap and you'll discover a novel fix.

My TF did the same when I first got it, and someone on this forum pointed me to this fix. You purchase a brass sink drain fitting (The one directly below the sink bowl). One that is 5 to 6 inches in length is what I went with.

Open the gas cap and push/hammer lightly the tube into the tank opening until seated. You'll then find that the gas can't slosh up the pipe when you corner or stop quickly, but rather past it. It cured my problem without the aid of any gaskets.

I might add as well that I usually only fill the tank 3/4 at most. Check the archives for more specifics as I've seen this reposted several times over the years. Good Luck!

Gene
P Burgess

Larry - I just stick the pump nozzle as far into the tank that it will go. Start filling the tank and when the nozzle automatically shuts off, don't top it off. This like the drain pipe will minimize the spillage, although neither is 100% Cheers - Dave
David DuBois

Larry, I'm pretty much with David. The exception is, if I'm leaving on a trip with a significant number of miles of expressway driving, I'll fill the tank to about three inches from the top and motor gently around the first few right hand cloverleafs. Bud
Bud Krueger

Thanksw to everyone for your ideas. I have always been careful to never fill the tank but this time I tried it only to get a check of the miles per gallon. Sadly, when the fuel came out of the filler neck while driving (full tank) it ruined the paint around the filler neck. The car was just painted a few months ago and now I have to get it back to the shop to get repairs made. Lots of fun!!!!!

Larry
LD Kanaster

Larry,
I found this one on the bargan table at local hardware store for $1.00.
The clearner wax is what I have used in past to clean up the spill before I put the pipe in.

David Sheward

Well, here is the latest on the leak problem. I drove to the paint/body shop and the plan is to repaint the fuel tank from the left tie-down strap to the edge. We are also going to try to fill the indentation in the tank that goes around the fill neck. Apparently when the fuel spilled into this indentation it then very quickly went under the paint. I see no reason for the indentation so I hope that by filling it (we haven't figured out what to use as yet) then if a spill occurs again it will run down the tank. The paint peeling is solely around the fill neck and perhaps 3/4" outward from it. Today the tank level was about 2 inches from the top when I drove to the shop and no fuel spilled. At the shop I opened the fill cap and the gasket-
material insert I mentioned earlier was soaked with petrol though none leaked out. I removed the insert and drove home and sure enough fuel spilled out. I reinserted the gasket-insert and had no further problem. Lesson learned--no more filling of the tank.

LD Kanaster

this maybe of little help..but my driver mg td gets filled up all the time and i have only had a problem when i filled it to the absolute brim...i only fill to the neck (which is a full tank)and have no problem at all. regards, tom
tom peterson

Larry,
Part of the problem might be:
Pretty sure that gasket should be under the "lip".
Hope you can see it here.

David Sheward

As a temp fix I wind a rolled up sheet of Kleenex around the filler neck and fix it with a rubber ring. Soaks up the spill ok so nothing runs down the tank any more. Plan is to install the Drain pipe as this seems to be the best fix for the problem
Mike
Mike Fritsch

David,

I think your suggestion is not the right one.

The gasket must be around the filler neck (see pic), not in the cap or under the lip, otherwise you obstruct the venting capacity.

Moss-USA part # 293-600

With this gasket no leaks of petrol. That is, on my TD #3966.

Jasper



JL Nederhoed

Larry,

IMHO - The indentation is where the gasket (sealing ring) goes...
Moss-USA part # 293-600

Jasper
JL Nederhoed

Jasper is correct,,, we have never had any leaks when the cap is closed,,, our gasket is on the neck as shown in Jaspers pics,, I always fill our tank right up to the neck,,,
The insert that L.D. put in actually seals where it should be sealed if the gasket was installed in the correct place,,,,
SPW,
STEVE WINCZE

I have to take another look but think I have a gasket where Jasper shows, but also one (Like in Larry's first pic) "under" the center lip. Been a while since I have looked close at it, and mine must not be right as I see everyone else has a rivot holding the center piece. I think mine has a screw there. Perhaps it had been replaced before I got the car?

Be a couple days before I can put up a pic. 3 digital cameras are in for a repair, (at a company that obviously wants no more of my business...cost over twice as much to fix as buy same camreas new!) new camera (different company) is on the way.
David Sheward

my car's gasket is also in the filler neck. regards, tom
tom peterson

Lots of good ideas are coming from all of you. Regarding my 'fix' about inserting a cover gasket as seen in my picture, the idea was to see if I could just block some of the fuel from spilling. It apparently did not work for a full tank but right now the tank is about 2 inches below the top and it works fine (though it gets soaked with petrol). Dave suggested that I cut another piece of the gasket material and insert it under the normal gasket. I had not thought of this. It makes sense, especially since the picture that Jasper has in his note clearly shows an indentation in the gasket from the cap. Mine does not show such an indentation and therefore cannot be sealing correctly.
As I mentioned in an earlier note, my immediate concern is to fill the 'moat' around the fill neck and repaint the tank. Hopefully any fuel spill will then run off the tank and make a mess (as one would expect) and not ruin the paint at the fill neck.

LD Kanaster

The leak seems to come from where the "split" is where the hinge is for the cap. Or at least mine did.
Looks like that is what happened to yours also?
Sloshed out there and got under the paint in front of tank where maybe they did not get a good coat of paint?
Plumbing drain seems, (so far), to be the best fix I have found. I put mine in with a homemade Nitle gasket and a smear of Permatex Ultra Gray.
Still carry some cleaner wax and check it but so far so good.

David Sheward

LD,
The outer ring in the cap indeed causes the indentation in the gasket. When the gap is closed this outer ring presses upon the gasket, not only preventing petrol to get spilled, but also lifting the vent hole a bit.
JL Nederhoed

David--good comment re the leak coming from the cap hinge. I will look into that. My other car (54 TF)also leaked fuel when the tank was close to full but I had no paint problems. The filler neck gasket on that car was new and definitely showed the expected indentation all around it from the closed cover. It seems that currently the best solution is still to increase the thickness of the gasket via an insert and then see if the cap makes a good contact. Other than that I can just keep using the round gasket-material insert that I currently have.
Thanks again.
LD Kanaster

DPO in training?
Is that what I am?

I honestly don't recall if I drilled and tapped this to take a screw or if that was the way it came to me.
(It's been a while ...and many beers ago LOL)
I do recall replacing a cork gasket under the center "disk" many years ago. It is still there (could use replacing again, it's kind of funky).
Pretty sure it had a "vent hole" in it just like the one Larry shows.

New camera got here today, as promised ..this what I have.

David Sheward

I recently purchased the filler opening gasket from Moss, #293-600, and installed. As several others have noted, the gasket fits into the lower slot ring. I also noticed that when I closed the lid, there was the appropriate "pressure" of a tight seal. Larry, I haven't filled the tank with gas and driven, but as you can see this seal appears to seal all around, even at the rear hinge area. Photo attached.

John

John Brickell

My tank will leak I overfill the tank. My solution is to put the pump nozzle into the tank as far as it will go. After it shuts off automatically, I add exactly 1 more gallon. I drive somewhat carefully immediately after filling. This works well and is accurate enough to calculate fuel consumption.

Frank Grimaldi
Frank Grimaldi

John has the correct instalation,, no need for a "drain Pipe", no need to not fill the tank all the way,,no worry about sloshing when going arond a corner,,


IMHO,
SPW
STEVE WINCZE

This thread was discussed between 17/05/2012 and 21/05/2012

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