Gas (petrol) cap gasket woes...

[mdsalemi]

So, some years back the original cork/rubber gasket on my gas cap kind of fell apart. When ordering a bunch of small parts from one of our suppliers (not nameless, I just don't remember!) I bought a rubber replacement, it was a distinctive blue in color. That was always too snug and gave me fits when replacing and locking the gas cap. So, a year or so ago I bought a better replacement from another one of our suppliers (still trying to find a receipt!). That fit well.

Yesterday, I filled the tank and lo and behold that gasket was soft, mushy, had swelled, and when I tried to push it into place on the cap, it started to come apart. Awful smell of fuel on the drive home from the gas station as I'm sure some fuel was coming out the back as the gasket was no longer working.

I don't have time to wait for a replacement so I ordered some specific fuel resistant gasket material from Amazon (cheaper than just the shipping from one of our vendors here) and will cut my own.

I'll amend the post here with photos when that arrives.

[Pawel66]

Fuel cap gasket topic again - the one from the MB dealer works for me for years. Just need to put a thin layer of oil on it form time to time, e.g. when you change oil.

[Paul & Dolly]

I regularly coat the cork gasket with vaseline,which seems to help the cap rotate smoothly.

Paul

[mdsalemi]

Fuel cap gasket topic again - the one from the MB dealer works for me for years. Just need to put a thin layer of oil on it form time to time, e.g. when you change oil.

I am not sure you understood the point of my post, but gasoline and oil is what destroyed the gasket. It was made out of an inappropriate material that could not stand up to petroleum products!

[Pawel66]

I did get it. It is disappointing to receive an item that is supposed to seal from gasoline leak made of material that is not capable of doing it. I also noticed that you, having experienced issues with tight application of your previous solution, embarked on a journey of experimenting with after market suppliers, failed and ended up cutting your own gasket.

That is why I mentioned a simple solution (MB dealer gasket) with a potential solution to tight application by means of lubrication. As alternative to a journey: original ,aftermarket, own fabrication.

[mdsalemi]

This was a considerably less costly and much quicker solution. I ordered this gasket material yesterday evening:

https://a.co/d/98CiRIP

And it was delivered this afternoon. Total cost about $10, shipping included. Took me about five minutes to custom cut and fit the new gasket. I have a lifetime supply.

The deteriorating gasket is quite sticky now, and yesterday was slimy and swollen clearly not standing up to the fuel. One may expect an off size or bad fit, but an inappropriate material was not something I expected.

Just because a part comes from MB doesn’t always mean it’s right. I’ve got plenty of experience with parts from MB that are just wrong or don’t fit or other issues. Not to say their gasket isn’t good but I needed a very fast solution.

Photo taken before I threw gasket in the trash.

I should mention that I did not leave the comfort of my home for any of this. Ordered it on my phone one evening was delivered to my front door the following day, and cut the new gasket at my kitchen island. It can’t get any easier. I will admit however that three massive Amazon warehouses are within 10 miles of me so we often don’t wait for much of anything from Amazon.

[VikDasor]

I have other issues going on with my original gas cap at the moment as all of sudden it does not want to thread on to the fuel tank so I am currently using my (spare) R107 gas cap at present which infact fits really well but does not look the part.
So not sure what's going on there.

[BobH]

I've never had a gasket in my fuel cap, never noticed any fumes inside the car or out, until recently, so, after reading the pro's and con's of cork and rubber, i ordered some
 
Fuel Resistant Nitrile Bonded Cork Gasket Sheet 200mm x 150mm 2.25mm

It's cork impregnated, looks like cork on both sides, smeared with some vaseline, as others have recommended, cap is slightly resistant to screw on, obviously tighter than having no gasket at all, i'll see if it stops the fumes, and how long it lasts

[BobH]

I have other issues going on with my original gas cap at the moment as all of sudden it does not want to thread on to the fuel tank so I am currently using my (spare) R107 gas cap at present which infact fits really well but does not look the part.
So not sure what's going on there.

Hello Vic, i'm sure you must have read this, but if not:

https://www.sl113.org/wiki/Fuel/LockingGasCap