Grease or Ground

Gents, a couple of questions<br /><br />Should I grease i exa. head bolts before torquing, or will it give a wrong torque ?<br /><br />When you take compression tests, is it neccesary to ground plug wires to old spark plug to avoid damage to power pack, or dosnt it matter .

Re: Grease or Ground

G DANE <br /><br />Good 'can of worms' you opened up!<br /><br />>clean dry head bolts + spec. torque = clamping force<br />>oiled head bolts + spec. torque = 2 X clamping force<br />>sealant or glued bolts = less clamping force<br />>loctite'd bolts + spec. torque = less clamping force<br />>greased or STP'd bolts + spec. torque = 2plus X clamping force and may pull threads<br /><br />>Cast iron block manufacturers recommend to lightly oil head bolts with engine oil or their own special lube.<br />>I can't find 'documented' marine recommendations.....maybe someone else can<br /><br />As far as the ignition system goes, use the easiest method to prevent spark voltage:<br /><br />-flick lanyard, or<br />-disconnect pack, or<br />-unplug stator, or<br />-if its a system where shut down is accomplished by throttle position, ground plug wires to block<br /><br />Good luck!

Re: Grease or Ground

Hello G Dane<br /> I like to chase all thread holes, clean all threads and use a little anti corrosion greese (anti seize)or what ever is appropriate (thread lock,etc ). My opinion is its more important to have even torque than actual number. As long as its fairly close.<br /> Yes I feel it is nessary to ground ignition.

Re: Grease or Ground

I like to run a tap carefully thru the threads to clean, clean up the threads on bolts, or new bolts...then lightweight threadlock. Thatta way they can be precisely torqued to specs. Recheck torque after motor has been run to temp and cooled.<br />Just a Thought