Small Engines (Lawn Mowers, etc.): small engine, engine mechanics, dumptrucks

Question
john i have a small question is there a guide small engine mechanics go by to set engine rpm's on engine do u have to look up specs on each one to set or is most set at certain speeds.thanks i was just curious also my uncle works on bobcats dumptrucks he used to work at golf course keeping up there equipment he told me compression on weedeater should not be under 100 is this true. thanks

Answer
Hello Andrew:

Usually 90psi PLUS or MINUS 10psi is the Normally the Low End Compression. Usually if the Compression is Less than 100 you May be having Idle or Power Problems. The Engine RPM is Usually Set at 3600rpms Maximum for 4 Cycle Engines. I Obtained a Wire Type RPM Gage from my Local NAPA Automotive Outlet. The Governor Control Spring When Purchased New and Not Having Been Stretched will Usually be the Correct RPMs for the Engine. All the OEMs Offer a Shop Manual that Covers the Particulars of Their Engines. Hope this Helps. I am Here if You Require More Assistance. Let Me Know What Happens, Please. Thanks.

Good Luck

Respectfully

John