So as the old saying goes, one thing leads to another. Was working the 318 Poly removing the exhaust manifold on the 66 W-200 when engine bolt broke in the cylinder head. When I drilled the stud to use a extractor the bit went through the end of the stud and water came out. Is this what should have happened? Those course/fine engine studs are only 1/2" long going into the head. I used a 5/32'" drill, the size specified for the extractor and did not go deep when I drilled. This was the first stud from the front of the block on the on the right side that broke.
I checked another pair of heads from a 305E V-6 1967 GMC and noticed from sticking a piece of copper wire into that same front hole that the wire passed through what think is a combination water jacket/cylinder head bolt passage. I am assuming this is why the water came out when I drilled?
Is it the shoulder in the middle of the engine head stud that keeps the water in head and is it recommended that I use some red silicone to make the thread seal?
On the 305E heads all the other bores had bottoms 7/8" deep except the front ones. Thanks so much in advance for your help!
Broken Engine Stud
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- Sweptline.ORG Pioneer
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Re: Broken Engine Stud
U got it. Bolt hole is into the water jacket. That's why they like to rust solid and break on removal. Silicone helps, but it also breaks down over time. I replace all the exh manifold bolts with grade 8's. Good to use anti-seize on them too.
- Wildergarten
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Re: Broken Engine Stud
I'm for blue loctite on a new stud and the antiseize on a bronze nut (Dorman still makes them). After extracting, tap the hole clean and blow dry.PwrWgnDrvr wrote: ↑Tue Sep 01, 2020 11:09 pmU got it. Bolt hole is into the water jacket. That's why they like to rust solid and break on removal. Silicone helps, but it also breaks down over time. I replace all the exh manifold bolts with grade 8's. Good to use anti-seize on them too.
'69 W200 (thumbnail)
'68 W200 (RIP)
'68 W200 383 NP435 3.53
'67 W200 383 NP435 4.10 w overload springs, Dana 60, PTO winch & flatbed dump, racks, crane, c-air (Max)
Mark Vande Pol
Wildergarten.org
'68 W200 (RIP)
'68 W200 383 NP435 3.53
'67 W200 383 NP435 4.10 w overload springs, Dana 60, PTO winch & flatbed dump, racks, crane, c-air (Max)
Mark Vande Pol
Wildergarten.org