ok when i get home i can take pics of everything cleaned up. as for clearance im not to sure. neil did all the work on it. i can find out though. the only way coolant could leak through would be cause of the orings correct?
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Ok, I'm here now, been away at a race so didnt know about this.
Just to clear up things so we all will be on the proper page, in this reply where it states "neil did all the work to it" ( no), all Neil did was port & bore & fit a brand new ESR cylinder. Just a typo I'm sure, but it could be looked at wrong by some & thats not me.
Now when I had the cylinder in hand for my work, I had no idea there was no spacer plate shipped with the cylinder kit like normal, but when the porting was being done to it, the ports were degreed in with the proper thickness of spacer plate needed to be used for that cylinder kit, so that the piston edge came up flush with the top edge of the sleeve.
As far as the head dome not being the proper size for the bore, it was measured & was the proper size for the 350 piston, even large enough for a couple size over bores when needed. Piston to bore was set up at 0.0030 like always for a Wiseco piston.
Now if this engine was running out of my trailer & I knew the rider, how they break an engine in, I might would set the clearance up tighter because I would have an eye on every step taken.
I know some ESR cylinders are set up with more piston to bore clearance, but when one leaves me it will be 0.0030 regardless of all the talk.
Ok, now after the PM I just got & answered back, if the wrong thickness of spacer plate was used & the piston was hitting the dome, the resulting problems listed I can understand probably are happening.
A normal standard thickness of spacer plate for this cylinder kit, should have been a 4.8mm thick plate & two base gaskets, which I understand now was not included in the kit.
One thing that might need to be checked, maybe for other than to thin of a spacer plate being used, is if by chance the sleeve has dropped in the cylinder, which sometimes can happen on the 250R aftermarket cylinders, not a regular thing on all of them, but will happen in a few.
If that has happened, then there will be a greater amount of clearance between the head dome gasket surface & the top of the sleeve, so it could be the inner o ring not sealing as it should & could end up with a coolant leak into the bore.
Those o rings can be a pain at times, trying to get them to stay down in the groove when installing the head, so that maybe could have been some of the problem as well.
Not uncommon when installing the head & torquing the head down, to shiver off a thin piece of the inner o ring, which is probably what that thin thing is.
Its not good either way & the o ring needs to be replaced if that does happen.
Another thing I would like all of you take note of, in the pic of the cylinder, take note of that front coolant passage over top of the exhaust port. I had no part in that machining of that area & like I mentioned, all I did was the cylinder porting & bore job.
This was a builders cylinder kit sent to me to finish with porting & cylinder boring.
Neil
