Rolling Your Own Gaskets

There are times when you can't find a particular gasket locally, or it's just unobtanium. You could always use silicone gasket maker but there are certain applications that are just too much for it to handle. That's if you trust silicone gaskets not to eventually lose chunks and do things like clog your oil pickup screen. I don't and, as a result, avoid the stuff whenever I possibly can. So what do I do when I can't find the gasket I need? I cut my own, of course. Sometimes you can even make a better gasket than what the local parts store is pushing as OEM. All of these reasons apply when it comes to the gasket I'll be doing today.

First of all, it's important to get the appropriate gasket material. You can't use just anything. Use the wrong material and you'll be sprouting leaks, or worse, very quickly. I picked up this roll of composite paper/rubber gasket material (suitable for most applications, with the exclusion of oil pans) from the clearance shelf of a local parts store for about two dollars some time ago. Let's put it to good use.

Here you can see the reason a store bought gasket isn't optimal for this particular application. The odd bulge on this intake port isn't accounted for on stock offerings and, as a result, the amount of gasket preventing a leak here is tiny. (Just about 1mm! You can see the imprint left on the second to last intake port below, the clean areas are what the oem gasket covered.) With a custom made gasket, there will be a good deal more space between you and a huge vacuum leak.

The first step is to simply make a pencil outline of the part by putting it down on the sheet of gasket material and running around the perimeter with your pencil. There's really no need to be careful, because we'll trim any excess later.

Now, it's a pretty simple matter to cut along the line to make our basic shape. Again, no need to worry about perfection. Leaving too much is just fine. Remember, it's easier to trim than it is to add material.

We have our basic shape. It's time to cut out the bolt holes. This is accomplished by placing the form on the intake as closely to it's final position as possible and punching through one of the bolt holes with an x-acto knife or something similar. No need to make the hole very large as some friction is important to hold the thing in place. Repeat for the remainder of the holes, keeping in mind that the gasket must lie perfectly flat. No waves or bumps at all or your new gasket will leak.

Now is a good time to begin cutting out the port holes and cooling passages. This should be fairly self explanatory. Try to start in the center of each hole to minimize the chances of poking a hole where a hole should not be.

Once that's all done, you can trim the outside to a perfect fit with your sharp blade and finally enlarge the bolt holes to ensure an easy assembly. Slop on the gasket sealer, assemble the parts and call it a night.

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