The Stovebolt Site Forums The Shop Area Engine Shop What gas-safe gasket material for fuel filter?

What type of gasket material do you suggest that I use to make a gasket for the Moraine Durex fuel filter on my '54 3100 235 Rochester B? (pic taken before bowl filled with gas) The body of the filter is warped a little, probably from years of overtightening the bowl.

I installed the filter a couple of months ago and made a new gasket from 1/16" Fel-Pro Cork-Rubber gasket material part #3018. It was a little too thin, so I cut another one and sat it on top of the first one. Both fit tightly in the body. I only drove it a few times. There were no leaks and it ran great.

Last week I removed the glass bowl to do some carb work. The truck had sat for about a month. The glass bowl was still full of gas. One of the two 1/16" gaskets fell into my hand. It was deformed like a potato chip. The other remained in the body of the filter and was also deformed when I removed it. When I finished the carb work, I reinstalled both 1/16" gaskets and started the truck. Surprise - gasoline came gushing out of the filter between the bowl and the body.

I cut a new gasket from 1/8" Fel-Pro Cork-Rubber gasket material part #3019. When I started it up, gas gushed from the filter again.

I thought that maybe the 1/8" cork would soften and conform to the filter body if I soaked it in gas before installing it. After soaking overnight - - it swelled up and GREW 3/16" in diameter. Even if I can use it, it will probably shrink to a potato chip shape again if the truck sits for a while.

What should I use?

A pic of the gaskets is below ...
> Top Row
1) 1/8" gasket, swelled and starting to wrinkle
2) Original 1/16" cork gasket that came with filter purchased on eBay
3) Rubber ring that was stacked with the cork gasket in eBay filter

> Middle Row
1) & 2) 1/16" gaskets that I cut. Shrunk and wrinkled.
3) Diagram for gasket.

> Bottom Row
1) Rubber gasket that came with Durex Filter purchased from Wrenchbender Ret. I have also seen four-slot rubber gaskets for Durex filters.

Click for gasket pic.

I searched on StoveBolt. Althought some posts suggested cork, some did not.

Thanks for your help,

Why not have a machinist face off the gasket surface of the filter housing flat again? It's a fairly simple setup in a lathe with a 4-jaw chuck, and you'll eliminate the source of the gasket distortion. Rubberized cork would be the material of choice, but you're whizzing in the wind trying to seal against a warped surface.
Jerry

Thanks Jerry,

Deep down, I know that the warped body is not good. Didn't think about having it turned flat.

What about the gasket? Is there something better than the Fel-Pro material that I used? Why did my gaskets distort so much? Even if the body is flat, will I still need to be concerned about the gasket swelling, shrinking, and distorting into a potato chip? I'm not looking forward to a gas geyser after the truck sits for a few months.

Once the gasket is in place, it won't have much of an opportunity to warp as long as the glass bowl is cinched up snug. Back when those filters were in general use, we seldom re-used a gasket. Anytime it was necessary to remove the bowl for cleaning, the gasket got replaced. Of course, the parts stores stocked them by the dozen back then.
Jerry

Thanks again -

I am always amazed at the knowledge on this forum. May be a simple answer, but it was a major problem to me. I'll cut a new 1/16" gasket after the body is trued up. I have two filters, so I'll let the shop use one for practice.

Thanks for your guidence.

Recently we purchased a fuel ump rebuild kit from these folks (not for a Stovebolt) http://www.moyermarine.com/index.htm
Our fuel pump as part of it has a fuel filter bowl.
In the kit came instructions (can't find them online) and a disc of reasonably coarse sandpaper with a hole in the middle.
the idea is you peal off the back of the sandpaper and stick it to the top of the fuel bowl, then use it by hand to sand the gasket seat in the filter housing flat. It worked quite nicely!

Could also be machined flat in the lathe (I would) but a piece of sandpaper is a whole lot cheaper, faster, and no need to remove the filter housing.

Another caution in the instructions was the cause of the warped housing to start with was over tightening of the clamp, and from here on out only lightly snug it enough to not leak and a tad more, don't go overboard tightening it.

for the gasket I recommend you just buy the premade ones that are a rubber and cork blend. I used to get them from the local tractor repair place and they always had the size I needed (I messed with all sorts of engines many with one version or another of a glass bowl filter), NAPA may also have them?

Grigg

Thanks Grigg,

I may try the sandpaper trick on a spare Durex filter that I have. I agree with you and Jerry that having it machined is the better fix.

The face of the filter body has a very thin bead directly above the rim of the glass bowl. The bead presses into the gasket to give an extra seal. I hope that a machine shop can preserve the bead.

I'll also check Tractor Supply to see if they have a gasket in stock. That would be too easy! I found a gasket for a glass bowl fuel filter in NAPA online that looked like my filter gasket, but the diam. was too small.

I keep the least amount clamping pressure possible on my glass bowl fuel pump and on the Durex filter. I see how the design is prone to warping.

I have a 48 1.5 ton and it has the mechanical fuel pump and filter assembly...got the glass to housing cork gasket at Tractor Supply.

I fixed the gasket problem on my Durex glass bowl fuel filter (I hope). The gasket leaked because the body of the filter had become warped from years of tension by the bowl clamp. Here's what I did:

Rather that having a machine shop turn the face of the body flat and true as Jerry suggested, I cheaped-out and pressed it in my woodworking vice. Stuck a couple of narrow pieces of wood where the clamp wire hooked onto the body. I tightened the vice a few of times a day over period of three days. I didn't crank down with brute force, just listened to my gut on this one. I tested this on a rough filter that I don't use before pressing my "good" filter.
(Vice)

Then, I did as Grigg suggested and stuck a ring of 100g sandpaper to the glass bowl and sanded the inside face true. Actually, I only had to remove a small amount of pot metal from the ring inside the body, not the entire face.
(Ring sanded true)

Finally I cut a new 1/16" cork-rubber gasket and inserted it into body. I installed the filter, started the truck, loosened the pressure on the bowl until it leaked, then tightend it about half a turn. So far - no leaks.
(New gasket)

Thanks for helping me.

Thanks for the information,that's a really nice write up and pictures.Just curious if this gasket would fit your filter bowl,it also fits the fuel pump bowl ? glass filter bowl gasket


Tim

Hi Tim,

The gasket in your link would not work on a Durex filter. The gasket must seal two surfaces:
1) The glass bowl to body near the edge.
2) The cup-shaped brass filter element to body near the center.

The seal for the bowl and the seal for the element are held in position by the ribs in the gasket. Fuel travels through the slots in the gasket between the ribs to fill the bowl. The element is pushed against the gasket by a spring inside the bowl. The brass filter element does not have a built-in gasket like paper elements for reproduction AC glass bowl filters.

My Durex filter had a rubber gasket like the one in your link PLUS a cork gasket like the one in my pics. The rubber gasket was probably added to seal the warped body.

Excellent solution!
Thanks for the followup and pictures.

Grigg

It'll be interesting to see how the cork gasket seals in the long term. Cork is somewhat porous and can allow low viscosity liquids to seep past.

Tiny -

Now you've peaked my paranoia. I'll keep an eye on it. (Just hope the leak doesn't start while I'm driving!)

Jerry and Grigg suggested cork/rubber for the gasket. I believe that the original gasket was cork, but the cork particles were smaller than the ones in my new gasket.

The cork/rubber swells and shrinks a lot. I'll change to rubber if leaks develop. Any suggestions about what to use?

I've seen old cork gaskets just like you made in that application. Run it and see how it does, I think you'll be just fine.

If it seeps more than you like find some cork/rubber because that's what the replacement glass bowl fuel filter gaskets are made of. Check tractor supply for an example, although not the shape you need.
NAPA may be able to get a roll or sheet of the material.

I see your link now, that looks right.
I've never had the swelling/shrinking problem you mention, never seen it before seeing your pictures. Could it be the ethanol issue, or poor quality material?

Grigg

If it does seep it most likely won't be a gusher. I've seen old cork gaskets too so I made a gasket out of cork for my fuel tank sending unit. I have seepage issues with it and can't keep a full tank of gas in the '38 because of it. I've tightened the mounting screws as much as I dare but no luck. In my case it's more a fume issue than a fire hazard. My tank is in the car rather than under so the fumes from the seep get pretty strong if I leave too much fuel in the tank.