Exhaust Leak

I purchased new exhaust gaskets for my 1980 kz440 and have been experiencing an exhaust leak around the left hand side flange at the block. With one gasket installed on each side I can wiggle the left hand side pipe an 1/8" or so in and out of the block. I then doubled up the new gasket along with the old one and it tightened things up but I still have a leak at the block. Anyone experience this or know of a fix beyond adding another set of gaskets? Thanks.

A single gasket in each port should prevent any exhaust leakage at the juncture between pipe and port.

Perhaps the split collars are too short.









Good Fortune!

Thanks for the feedback Patton. The flanges and exhaust are stock so I'm not sure the flanges are the problem. I have noticed a couple gasket options for this bike though. One being a flat gasket with a little thickness to it, and the other is a copper gasket much like the one shown in your picture. Maybe changing to the copper will help.

Here's Z1E's listing for KZ440 exhaust gasket.

www.z1enterprises.com/catalog/product/vi...-gasket-kz440-kz400/

From the picture, it looks similar to the slightly thicker Suzuki exhaust gaskets sometimes suggested for the larger KZ models when the rounded stock copper gasket seems not quite thick enough.

Good Fortune!

I couldn't get my 750 to seal up properly despite new copper crush rings and very careful assembly. Solved the problem by doubling up on the gaskets; used both a copper crush ring and a flat gasket as well. Had the pipes on and off several times before figuring all this out.

I'm thinking that's my next plan of attack. I think the old ones doubled up with the new ones just aren't thick enough. Hopefully two new ones as you suggested will fix it. Thanks!

The length of the split collars determine how hard the pipe flange is pressed against the gasket when the clamp is tightened.

A too short split collar won't press the pipe flange hard enough against the gasket when the clamp is tightened. Which results in a "loose" fit subject to leakage.

A too long split collar should press the pipe flange hard enough against the gasket as the clamp is being tightened to thereby fully seal the juncture between port and pipe, but won't allow the clamp to seat against the head, and probably leave the clamp nuts insufficiently torqued. All of which presupposes enough exposed thread on the studs to get the clamp nuts started.

Ideally, tightening the clamps against the head should result in "perfect" pressure of the pipe flange against the gasket.

I think the effect of adding a second gasket is the same as fitting longer split collars.

If all else fails, some high temp copper sealant can be used on each side of the gasket.

Good Fortune!

Installation tip --- use dabs of high temp copper sealant to hold the gaskets inside the ports while maneuvering the exhaust system into position and getting the clamp nuts started. Perhaps also tape the split collars together. Idea being to help keep all the components from separating and falling apart during installation. Such as gaskets falling out of ports, and split collars taking flight. :pinch:

Good Fortune!

Thanks!

You said one pipe was still loose after tightening down the nuts. Look to see if you're running out of thread on the exhaust studs. If so, the problem is at the collars or the studs themselves. I think I remember on my bike that the studs had less thread on the head side, meaning if they were reversed it might cause this problem.

Also, make sure the mufflers or crossover pipe clamp bolts aren't getting hung up on something. doh.

Thanks fellas