16vsilverstreak
XS650 Enthusiast
If the head is pulled off does the base gasket need to be replaced? The only air cooled engine I've worked on is a 911 flat six and when we pulled heads we pulled cylinders. Thanks
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Base gasket question
- Thread starter 16vsilverstreak
- Start date
If you break the cylinders loose from it then I would say yes - and it's pretty hard not to. If you pull the head, it's just plain silly not to remove the cylinder block as well so you can inspect things (rings, bore, etc.). If you pulled the head to replace the front cam chain guide, it's near impossible to insure the new one is mounted perfectly straight unless the cylinder is off and you can measure side to side at both the top and bottom of the guide.
Are you pulling the head to replace the front cam chain guide?
If you are careful and don't break the seal on the base gasket when you lift the head, then you won't need to replace it.
If you might break the seal and not realize it until the engine is together and running and you find it leaking.
If your compression is good, then you can lift the jugs off, put on the new gasket, replace the jugs then put the head back on. This can be done without new rings, or even honing the cylinders.
If your compression isn't so good then I might pull the jugs, measure the piston to cylinder clearance to see if it needs anything.
With the jugs off you can measure the rods big end clearance and swing of the small end.
Your repair manual tells how to check these things.
Leo
If you are careful and don't break the seal on the base gasket when you lift the head, then you won't need to replace it.
If you might break the seal and not realize it until the engine is together and running and you find it leaking.
If your compression is good, then you can lift the jugs off, put on the new gasket, replace the jugs then put the head back on. This can be done without new rings, or even honing the cylinders.
If your compression isn't so good then I might pull the jugs, measure the piston to cylinder clearance to see if it needs anything.
With the jugs off you can measure the rods big end clearance and swing of the small end.
Your repair manual tells how to check these things.
Leo
16vsilverstreak
XS650 Enthusiast
I might as well "do it while your in there". I was going to decide how far in I was going to go after I looked at the cylinder walls. I originally was going to replace the valve seals and be done. I'll tear it down and replace what needs to be replaced. Thanks for the input.
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