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Frozen head studs

Tproject

Senior Member
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I removed the head from a BJ7 engine that has been sitting around for years. Four of the head bolt studs will not budge. I have tried all types of liquid thread busters, double nut solution and tapping for vibration to loosen rust. Nothing worked yet. Heat is probably next unless someone has solved this problem in the past?
 
Studs are pretty cheap so I would use a pipe wrench and plan on replacing them. Do not re-use them if the pipe wrench teeth put grooves/marks in them because they could be stress risers that could cause failure of the stud.
 
Tproject said:
I removed the head from a BJ7 engine that has been sitting around for years. Four of the head bolt studs will not budge. I have tried all types of liquid thread busters, double nut solution and tapping for vibration to loosen rust. Nothing worked yet. Heat is probably next unless someone has solved this problem in the past?
A 50/50 mix of acetone and auto trans fluid is really good penetrant plus using dry ice works wonders in shrinking the studs so that the mix can penetrate the space and you might even be able to remove the studs right then. I've used refer ice on stuck wire wheels before and they slid right off the hub! I plced the ice inside the hub and held it there with a rag.
 
I have tried the 50/50 mix of acetone and auto trans fluid. Guess what, it doesn't mix and it doesn't work. Its like oil and vinegar. It's a myth. My advice is to buy a good product that actually works. But, if that concoction works for you, then you got lucky, or it really wasn't stuck that badly.
 
I thought I would make it a trifecta of PNW Healey racers.....
I've had an unusually amount of difficult to remove nuts and bolts lately and have have great success with this method. Heat the part with a portable torch, then blast it with CRC freeze off, https://www.crcindustries.com/files/Freeze-Off%20Brochure.pdf This has worked every time so far. I would take Dave's advice and replace the studs regardless, well worth the replace price.
 
BoyRacer said:
I have tried the 50/50 mix of acetone and auto trans fluid. Guess what, it doesn't mix and it doesn't work. Its like oil and vinegar. It's a myth. My advice is to buy a good product that actually works. But, if that concoction works for you, then you got lucky, or it really wasn't stuck that badly.
I suspect that the acetone might evaporate somewhat but the trans fluid won't. I think the dry ice did most of the loosening work. I had a friend who used to put his problem parts in his large freezer overnight and bragged it worked everytime.
 
A method I frequently use is a little heat (it doesn't take a lot) and wax. The application of heat for a little thermal expansion, and *touching* a candle to the stud will draw the melted wax in, wicking it around the threads.

Now the threads are lubricated with the wax and the fastener will be removable.

Too much heat and the wax boils without being draw into the threads.
 
Report:
I started at the top with the pipe wrench solution from red57. Tightened slightly then screwed out, worked on all four. I had used a marvel mystery soak on them for the last two weeks which might have helped. Will replace all studs.

Thanks red57 and everyone else since I may need other solutions as I progress with this engine.
 
One more suggestion. When you replace the studs - do not follow the factory manual and apply any torque to the studs. Apply a touch of oil to the threads and tighten them finger tight. Only finger tight! You will get better final torque results when you torque the head nuts (75 ft/lbs).
I just torqued my nuts on a fresh motor and I'm ready to rock and roll with Dougie, red57, and all of the other British race cars at the Pacific Northwest Historic races at Kent, Washington, June 29 - July 1.
Oh, I almost forgot to mention, I use ARP studs and nuts, so I torque my nuts to 85 ft/lbs.
 
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