Author Topic: '76 cb750F exhaust stud removal  (Read 7049 times)

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Offline pjlogue

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'76 cb750F exhaust stud removal
« on: October 16, 2024, 02:26:32 PM »
I purchased a '76 750F engine that has 16,000 mi on it.  I am in the early stages of rebuilding the motor.  What I need to do is remove the exhaust collar studs.  I have tried three nuts jammed together, heat, vice grips on the non-threaded part while using the jam nuts and the stud is still rock solid.

Any suggestions for removing them?  Suggestions would be greatly appreciated!

I plan on using my stock exhaust with the exhaust nipples that are on my 750K,  I also don't want the studs sticking out when I go to put the rebuilt engine into my bike.  Frame is like new condition and I know the exhaust studs will trash the finish on the frame. 

-P.

Offline calj737

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Re: '76 cb750F exhaust stud removal
« Reply #1 on: October 16, 2024, 03:09:50 PM »
There is no amount of heat that is too much. The head is basically a huge chunk of aluminum and that is a massive heat sink. Swap from propane to MAPP gas. Heat the head around the stud too. Make sure the stud is cherry red, then spray ample amounts of PB Blaster into the threads. Then wiggle back and forth between tightening and loosening the stud. Don’t try to twist it straight out.

Tightening sounds wrong, but if it won’t budge tighter, then it won’t loosen up. Keep up with the heat and PB Blaster; it WILL come out. Be patient and don’t brute force it. You’ll shear it off then you’ll have a new mess on your hands.
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Offline pjlogue

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Re: '76 cb750F exhaust stud removal
« Reply #2 on: October 16, 2024, 04:09:33 PM »
Thanks for the advice.  I think I need a bigger torch.  I have the mapp gas but the torch head is quite small and isn't throwing out a lot of heat.

-P. 

Offline Tracksnblades1

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Re: '76 cb750F exhaust stud removal
« Reply #3 on: October 16, 2024, 08:01:17 PM »
Sometimes the rattling impact of a 3/8” impact can work wonders.  a few hammers tighter, a a few hammers looser, tighter-looser, back and forth,  back and forth, watching your socket for progress, can do more that slow steady gorilla torque that just twist things off.. patience patience patience is the key…😇
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Offline willbird

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Re: '76 cb750F exhaust stud removal
« Reply #4 on: October 18, 2024, 08:49:57 AM »
Yea a rosebud on an oxy acet torch is what you want to heat things red warm when they are threaded into an aluminum heat sink.