RXL Gasket Information

I get asked all kinds of questions about the RXL’s, and a frequent one is, “What gaskets do I use?”

The RXL engines were made 44 years ago; you can no longer just order them from a dealer. So here’s what I’ve learned, mostly from Doug Monson, who built almost all my engines for me.

1. Do not use Winderosa Gaskets. They just suck.

2. For the 250 and 340 twin motors (including the monoblock 340) as well as the 439 triple motors, use the same era TXL base gasket. They may have to be trimmed or cut a little, but they work the best.

3. 340 Individual cylinder engines use the same head gasket as the Centurion 500 motors

4. For 250 and 440 triple heads, you need original RXL gaskets – good luck, they can be tough to find!

5. For the 440 twin RXL Motor: The same era, 440 TX gaskets will work for the base gasket and perhaps the head gaskets.

6. All the water manifold gaskets are the same as the Centurion, and exhaust gaskets are the same as any same size Polaris Engine.

7. On the 440 triple, be careful of the thickness. There are two sizes 43(?) and 65(?), and you need the smaller of the two.

8. If all else fails, contact Kevin at Cometic gaskets to make what you want need – except he needs the original gasket to copy, or the head and cylinder, and what thickness you want them.

Hope that helps – and oh.. and please don’t contact me about this because that’s is all I know about it!


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