Leaking Head

[timmymac]

hi can anybobdy help.

i am having trouble getting the head to seal on my sherco 250 2006

i have had the barrel religned etc and and have come to putting it back together and water keeps getting into the barrel each time i run it for around 30 seconds.

i have 2 new o-rngs inner and outer and the small ones for the screws so i imagine no sealer is required

i am fitting an s3 head i dont know if it makes any difference but it also leaks with the old head aswell.

also the supplier of the head wasnt sure if the s3 head needed the samll o-rings can anyone clear this up.

thanks

[copemech]

hi can anybobdy help.

i am having trouble getting the head to seal on my sherco 250 2006

i have had the barrel religned etc and and have come to putting it back together and water keeps getting into the barrel each time i run it for around 30 seconds.

i have 2 new o-rngs inner and outer and the small ones for the screws so i imagine no sealer is required

i am fitting an s3 head i dont know if it makes any difference but it also leaks with the old head aswell.

also the supplier of the head wasnt sure if the s3 head needed the samll o-rings can anyone clear this up.

thanks

That does seem a bit odd as the things normally go together fairly easily.

As you state this cyl has been relined, one would want to insure the top surface is perfectly flat and smooth. I would likely use a short machinist rule or something similar accross it to insure the top surface is good.

Presuming the head is also flat and the grooves clean, you would want to closely inspect the o-rings to insure one not pinched or damaged in a prior installation attempt. Use grease to hold them in place during install so nothing moves. Sealer is not needed.

Hope that helps.