Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

I have a Techumseh HMSK 80.  I An thinking of milling .020 off my head for more compression and hopfully more power. What can I exspect if I do this?  I'm trying to make it a 9-10 hp engine or at least increase the torque.

First things first- Get a Tach and check the rpm your emgine is running at. I bought a new commercial grade Toro mower with a 6hp Kawi several years sgo and it didn't cut well at all. When I checked the rpm it was turning at 3150. I adjusted it to 3500 and the performance difference was considerable. If I am not mistaken your engine is rated for 3600RPM. If it is running several hundred less than that you need to "up the ante"! A lot easier than milling the head.In addition if you have a fixed jet carb and not the adjustable one I fear you are in for some difficulty at the higher compression. Marc

Thanks for the reply. What do you use to check the rpm? how do you adjust the gov?

bus708 wrote:

I bought a cheap tach off of ebay. One leg goes to ground and the other wraps around the plug wire.It also has a mode that acts as an hour meter. There is another type that vibrates when you hold it near the head. When I was a kid and used them for model airplane engines they were sold under the name "Vibra Tach". Briggs makes a similar product today. As far as setting the carb you need to look at the Carb section in the tecumseh medium block engine repair manual which can be found on line if you do a google search. Advice: Do your research and due diligence BEFORE you start playing with the engine.It will be time well spent. Good Luck, Marc