I have a 1995 88 special evinrude. I recently installed a thermostat and the head bolt that I used will not torque as tight as it should be. Should I remove the head bolts, retap them, and use new bolts?
It may not be as easy as that if the threads are stripped.Since the block is aluminum and the bolts are steel,I'm almost certain the the bolt holes will need to be heli-coiled,oversized,or backfill welded and remachined.Good luck.
Your threads are probably stripped. Install a helicoil. They come in a kit available at NAPA auto parts stores. Get comfortable with them you will need them again sometime. See you in St. Pete.
The helicoil as middleground explained so nicely simply requires that you drill out the old threads with a specified drill size and retap the new hole with a tap supplied with the kit. The helicoil is inserted (screwed) into the now larger tapped hole and the internal diameter of the helicoil spring (stainless steel) fits the original bolt diameter. Now you have new stainless steel threads with a stainless steel bolt. Its better than OEM.
I'm no expert, but I would!<br /><br />Having said that, it's not like your driling out a spark plug hole, so you probably wouldn't get any swarf inside the cylinders.<br /><br />Good luck<br />Steve
Steve is right. None of the head bolts should go through to the cylinders. If you want to play safe, coat the tap with some heavy grease. This will catch the "swarf" (that's a term I ain't heard before) as you work the tap.