sanding the head

stevenflintrichards

stevenflintrichards

New Member
so far every engine i have seen has a gap on the head , i wet / dry sanded the head until that centre ring was completely gone and the head was flush . any one else do this it has way more compression and does not leak at all it is a 66/80 cc slant head . i may end up doing this on every engine i work on. what do you all think ?
 
I've always 'lapped' the cylinder head and cylinder gasket mating surface. Along with proper torque, 120 to 140 inch pounds on the stud nuts (throw the acorn nuts away) you should have a good seal. When sanding the head lay it on a known flat surface, glass works best, and rotate the head in your hand so you don't sand an angle into the gasket surface. I like to coat the area with 'Magic Marker' to give you some reference as to when you've removed the high/low spots.

Replace the acorn nuts with shouldered hex nuts. The acorns are notorious for bottoming out on the studs and not tight against the cylinder head.

Tom
 
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acorn nuts ruined an engine right after i had it broken in and bottomed out pulling the threads out of the block i also have bought a torque wrench that is in inch lbs .
 
While you have the cylinder head off try this: Double nut the studs, you can do one at a time, and torque them into the engine case. The same 120 to 140 inch pounds works. That way you know the studs are tight. Some will suggest to use thread locker on the studs but I don't and have never had one loosen.
After the engine has reached operating temperature a couple of times re-check your cylinder head nut torque and you shouldn't have to worry about them again.
Good luck.
Tom
 
yeah 2 door i am glad i joined this forum , im noticing these ht engines are of kinda poor quality but i wonder if there intentionally produced unfinished to keep the cost down knowing we have to finish machining them i dont mind i like learning but i wish these were american made
 
Look at it this way, Steve, if they were made here, we probably couldn't afford them :)

And, look at all the experience you're gaining.

Tom
 
yeah sounds good to me but polishing and sanding that ring out of the head made a world of difference the new engine idled on first start has way more compression how much i dont know till i buy a gauge but no head leaks and cant push start it have to be sitting down thanks to 2door and every one on here that post , im having fun learning new things almost 20 yrs working on mopeds and other small engines but these are like nothing i ever seen im keeping it under 25 mph for 100 miles but i am giving it burst of up to 75% throttle here and there
 
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