Pelican Parts Forums - So this is what they mean by a head stud problem?

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Quote:

Originally Posted by expernet (Post 6502164)

Since the stud is supposed to match the expansion of the case you have to be quick and make sure you are not heating the stud too.

Try wrapping the stud in a wet towel to reduce it's heating relative to the heated case...

Judging from the look of the sealing surfaces and blow by on most of the cyl the studs broke after the engine was sitting.
Bruce

Quote:

Originally Posted by expernet (Post 6502164)

So here is what I learned:

The $19.95 screw /stud extractor from Sears is a must have. Makes the job simple

Some studs must still be heated, I heated on the inside of the cylinder barrel along the base of the stud with a good old bernzomatic.

Since the stud is supposed to match the expansion of the case you have to be quick and make sure you are not heating the stud too. I had my helper put torque on the stud and at the right temp it will give, turn fast or it will lock up again.

I am only replacing the lower studs , Mainly because of the stress to the threads (not because I am cheap even though my kids say I am)

Stay tuned for reassembly!

The heat needed is not for "expansion" of the case, its to break the loctite.

With broken studs welding on a nut works great and the heat from welding is enough to break the loctite. Then an impact gun (cheap electric works fine) on the nut.

It's on the road

not bad, oh, by the way, your labor-priceless!