HSSK50 small block mods
- Thread starter delray
- Start date
ok guys here is what i was work on for a head gasket. initially it was for another engine for racing(clone). i was working with gentleman on making a copper head gasket in different thicknesses and he was also making it to my bore size. this is where it gets interesting. factory gasket on the clone is about .050 over the bore size. told me he could make the copper much smaller. closer to the bore size and when the copper was torque down the copper will only travel about .001 in word. so i end up making the gasket much smaller to the bore size. this too now help increase the compression with out milling so much off the head and on thickness of the gasket. at the same time i was asking about hs-50 gaskets that he already had made up in the pass and that he could make them in .042 and .032 so i got one of each for now with my clones gaskets(ship together)
after getting my hs gaskets i set one on top of my block and that too i notes the gasket was about .050 large then the bore. with my 2.795 bore i could have him make the circle part much smaller. of course this would only work on this bore size and the bigger bore you might only be able to go little smaller. every little bit would help specially on the small bore hs-50's and i can get the gasket in a .032 thickness.
after getting my hs gaskets i set one on top of my block and that too i notes the gasket was about .050 large then the bore. with my 2.795 bore i could have him make the circle part much smaller. of course this would only work on this bore size and the bigger bore you might only be able to go little smaller. every little bit would help specially on the small bore hs-50's and i can get the gasket in a .032 thickness.
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there's a guy on ebay selling copper hs50 gaskets at .042" thickness. they are only i think $10. he also says he can make other thickness. but i've never heard anything good about copper gaskets. my understanding is that they must be annealed before use?
http://rover.ebay.com/rover/1/711-5...0001&campid=5335845805&icep_item=313010930171
http://rover.ebay.com/rover/1/711-5...0001&campid=5335845805&icep_item=313010930171
yes clay, you need to anneal the copper first. then take a red scotch pad to the copper and then apply permatex copper spray or this toyota gasket sealer material that i seem to see alot of gokart guys use and engine builders. thats the two biggest ones that i see pop up. there is other products that might also work.
here's the engine done and ready for a mount. then i'll make an exhaust and intake/carb once it's mounted on the minibike. I added an alternator to the CDI ignition. it's the small version but it will run an LED headlight just fine. note the use of an old style 4 leg pull start and blower housing.
http://www.pinrepair.com/minibikes/p/hssk50crank4.jpg
http://www.pinrepair.com/minibikes/p/hssk50crank5.jpg
http://www.pinrepair.com/minibikes/p/hssk50crank4.jpg
http://www.pinrepair.com/minibikes/p/hssk50crank5.jpg
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i set the stock head gasket on the block and that too has quite a bit of clearance between the bore and gasket. i'm sure it was one gasket fits all. meaning it was made for the big bore blocks too.
i also did a quick measurement of the thickness that came out too about .063 maybe little smaller if i squeeze the calipers.
i also did a quick measurement of the thickness that came out too about .063 maybe little smaller if i squeeze the calipers.
not much going with my engine build now . it's kind of on the back burner with all my racing stuff going on now. i just finish up coating a racing piston so i thought at the same time i would give the tecumseh piston the treatment too.
before picture of the piston clean up and looking just like new.
products i use where made by a company called Cerakote. piston coating is a oven cure ceramic thin film thermal barrier coating designed to be applied on the top of pistons, on the top of valves, and the combustion chamber on a cylinder head and the side coating is a Micro Slick used to assist in reducing friction where.
before picture of the piston clean up and looking just like new.
products i use where made by a company called Cerakote. piston coating is a oven cure ceramic thin film thermal barrier coating designed to be applied on the top of pistons, on the top of valves, and the combustion chamber on a cylinder head and the side coating is a Micro Slick used to assist in reducing friction where.
part number for the piston coat is V-136 and the MICRO BLACK IS C-110
Cerakote Coatings & Cerakote Swatch Samples | Shop All Products
Cerakote Coatings & Cerakote Swatch Samples | Shop All Products
have you run that piston yet? Been curious about that one and actual fitment in an HS block (thinking possible deck height difference?). Supposedly after 2005 they were going to coat and redesign to the elliptical style on all the remaining small frame pistons to match that low emissions designed one you got according to their publications.
thanks, I’ve wondered about those for a couple of years now, but most of them I have worked with (hs50) were the early bore size. I have an NOS big valve/small bore ball bearing sbh that I wanted to get a std sized one of those for it....have been watching for a junk engine off a mower that used them or a really cheap used one to check measurements from before I ordered a new one. Thanks for the info!