I changed the head gasket on an hs50. The head was fine, I cleaned it up and put on a new gasket. I torqued it down to 175 in/lbs. Ran the motor and it was bubbling around the head on the left side. I torqued it to 190 in/lbs and it's still bubbling around that same area. I want to torque them all over again. If theres oil going past the gasket, do I have to take the head off and clean it up before tightening again? The manual says between 160 to 200 in/lbs max. anything else I should look for? where it might be leaking.
head leak hs50
- Thread starter jscap99
- Start date
Sounds like you have a warped head, or possably you got dirt under the gasket when installing? Were the mating surfaces on the head and block ok and not burned? I'd take it apart, check for warpage and dirt, if all that is ok, get a new gasket and torque the head bolts down in the correct sequence, see what happens. Also, while you have the head off, run a tap in all the head bolt holes, make sure they are clean and the bolts are not bottoming before they are tight.
Coop
Coop
Last edited:
Some head bolts stretch and bottom out before the gasket crushes. Actually all the new cars that come off the assembly line and even torque specs are just for stretching head bolts. The days of of 65 foot punds are over, now its get your biggest impact gun and run them down. And if you do follow the instructions it will tell you 35 foot lbs.,50 foot lbs., then turn an additional 90*.
Also the newer gaskets are tri metal wich mean three layers of metal. They have a better heat transfer and can take the abuse of the different metals expanding and contracting due to heat. For instance a aluminum head and iron block. Or sleeved engines. BUT ALL REQUIRE A SPAY SEALER. You can get it at any parts store for $6. Its a copper spray just for head gaskets.
SO my advise is to take the head off one more time get a piece of 320 grit stapple it to a flat surface and with a circular motion rub the gasket surface a little and check for spots that didnt get scratched. IF there is a big area that didnt get scratced the switch to 180 to cut it down then swich back to 320. Get some new bolts or cut the ones you have. These are small engines and the tolerences are big so there is lots of room for error. All my engines I put together with impacts and have had no problems.
Also the newer gaskets are tri metal wich mean three layers of metal. They have a better heat transfer and can take the abuse of the different metals expanding and contracting due to heat. For instance a aluminum head and iron block. Or sleeved engines. BUT ALL REQUIRE A SPAY SEALER. You can get it at any parts store for $6. Its a copper spray just for head gaskets.
SO my advise is to take the head off one more time get a piece of 320 grit stapple it to a flat surface and with a circular motion rub the gasket surface a little and check for spots that didnt get scratched. IF there is a big area that didnt get scratced the switch to 180 to cut it down then swich back to 320. Get some new bolts or cut the ones you have. These are small engines and the tolerences are big so there is lots of room for error. All my engines I put together with impacts and have had no problems.
