Lower left stud (facing the motor) on a PR-3 head will not thread in.

The size of the bolt is a M8 1.25.

Any recommendatiosn on where to buy an "oversized stud? Or do I need to drill it out and make new threads?

If this is the case do I run any risk of hitting an oil or coolant passage? Also what size would you recommend I drill the new hole out to. I am lost.

THanks for the help. Jason

 

HeliCoil?
or the other thing, what are they called, TimeSerts??

 

I have no direct experiance, but I have herd its risky to drill out the hole because of nearby coolant passages.

 

I have heard of these heli-coil things before. Is this somethig you can readily pick up at a hardward store? Where could one obtain a heli coil?

Also I am not familiar with a time sert. What is that? Which more readily available and effective?

 

A Heli-Coil takes a little practice and the kit will cost about $30, just for one size.

You could always drill and tap a larger size—take your choice: 10X1.25, 10X1.50, 3/8X16, 3/8X24.

 

I think drilling and tapping would be the easist thing to do.

But... Will I be clear of any oil/coolant passages if I take it up one size?

M10 1.25 seems to be pretty big. Is 3/8 16 bigger or smaller than that?

 

Need more help please.

 

3/8" X 16 is a little smaller than the 10mm stud.

 

i had the same problem and took it to a machine to helicoil it for 20 bucks.

 

Thanks for all the help guys! I appreciate it.

I ended up tapping the head manually with a 3/8 16 tap. USed a 3/8 16 stud and it seems to have taken care of the problem. Now every time I take the damn header off I will be doing the old 12,12, 12, 12, 12, 12, damn umm, crap, oh yeah 9/16.