Ever seen a GPW engine cracked on top of the head?
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Ever seen a GPW engine cracked on top of the head?
Hi all,
Thought you might find this of interest. I'm familiar with many of the usual places a GPW block cracks, but I don't know that I've seen them break like this around the head bolts and valve seats:
This engine, which is an early '45, was running when I bought it and I'm thinking it's worth putting back together and see if it runs without any issues. Worst-case scenario is if it fails, I'll have the spare '44 block that's correctly dated for my December '44 GPW bored, stitched, and time-serted to bring it back to life.
Anyone run into this before? Any ideas as to the cause?
Thanks,
John
Thought you might find this of interest. I'm familiar with many of the usual places a GPW block cracks, but I don't know that I've seen them break like this around the head bolts and valve seats:
This engine, which is an early '45, was running when I bought it and I'm thinking it's worth putting back together and see if it runs without any issues. Worst-case scenario is if it fails, I'll have the spare '44 block that's correctly dated for my December '44 GPW bored, stitched, and time-serted to bring it back to life.
Anyone run into this before? Any ideas as to the cause?
Thanks,
John
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Re: Ever seen a GPW engine cracked on top of the head?
Cracks around the head studs are not so common & can be caused by torquing the head studs into the engine block when they are meant to be fitted with sealant & just over finger tight.
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TO DIAGNOSE, TROUBLESHOOT OR FAULT FIND ANY AUTO SYSTEM....
Understand how system parts interact with one another. GOOD parts can then be established & the NOT GOOD problem/s part/s isolated for repair or replacement.
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Re: Ever seen a GPW engine cracked on top of the head?
John
Luc's spot on. I 've seen those same cracks on gpw engines a few times myself. Was worried the first time but the Engine ran without any problems. Got to say they were all on engines that had the heads bolted on. Don't recall seeing the cracks on later engines fitted with studs.
regards Nick
Luc's spot on. I 've seen those same cracks on gpw engines a few times myself. Was worried the first time but the Engine ran without any problems. Got to say they were all on engines that had the heads bolted on. Don't recall seeing the cracks on later engines fitted with studs.
regards Nick
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Re: Ever seen a GPW engine cracked on top of the head?
Thanks for all your input. This bolsters my initial thought of putting it back together and running it. If problems develop at a later date, I'll go over to plan B.
Will post updates on this thread for those who might be interested: http://g503.com/forums/viewtopic.php?f=144&t=295942
Sincerely,
John
Will post updates on this thread for those who might be interested: http://g503.com/forums/viewtopic.php?f=144&t=295942
Sincerely,
John
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Re: Ever seen a GPW engine cracked on top of the head?
Now, when I have that, (common on GPWs as I assume Ford's casting house was taking some shortcuts), I always put thread inserts in the stud holes, and install hardened seats in the valve seats. Maybe not necessary but then I know nothing bad will ever happen to it. It's in the machine shop anyway.
Last one I did needed valve seats anyway as they had been ground too much.
Last one I did needed valve seats anyway as they had been ground too much.
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Re: Ever seen a GPW engine cracked on top of the head?
Maybe a bit off topic, but the mention above of bolts being used rather than studs answers a question I had about the engine I bought a few weeks ago. It is a WW2 engine, with head bolts rather than studs, and I was wondering whether that was original. Maybe, maybe not?
All of the other Jeeps I have owned have been post war, so the bolts struck me as odd.
All of the other Jeeps I have owned have been post war, so the bolts struck me as odd.
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None of us are as smart as we pretend to be.
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Re: Ever seen a GPW engine cracked on top of the head?
What’s the date on your block? GPWs transitioned from bolts to studs in Nov/Dec ‘44 as best I know.
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Re: Ever seen a GPW engine cracked on top of the head?
Overheating the engine over the years will also cause those cracks. you’ll be fine after rebuild
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Re: Ever seen a GPW engine cracked on top of the head?
Put a bad ass Copper Head gasket on it , you’ll be good to go
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Re: Ever seen a GPW engine cracked on top of the head?
Depends on how many used Jeep engine blocks one has inspected. These cracks are quite common, especially on Jeep engines that have been driven while overheated.
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