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Author Topic: Engine wall casting thickness.  (Read 1013 times)

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Offline stony

Engine wall casting thickness.
« on: June 26, 2014, 10:03:52 AM »
I am getting ready to start serious work on my engine, however it has a freeze crack in the block wall.  Yeah, but I was young and dumb.  Anyway by now you probably know I like to do stuff myself, so am going to try Lock-N-Stitch pins for the repair.  So here is my question, how thick is the casting on the side of the block?  The metal is slightly displaced on the top of the crack (a few thousandths), so would like to grind it flat before drilling and pinning.  Any of you guys tried this?  Have another block if I really screw the pooch on this one so going to give it a try.
Terry
1949 CJ3A 11159 body 11225 engine 11140
On preservation vs. restoration:Roscoe Lee Brown "the Cowboys" when he met the whores on the trail:"Well, I have the inclination, but not the time”.

Offline F Bill

Re: Engine wall casting thickness.
« Reply #1 on: June 26, 2014, 02:20:28 PM »
Can you show us a picture of the crack and the surrounding area? The first thing you do with Lock-N-Stitch is drill a hole in the crack, so you might do that just to see how thick it is.....You also want to clean everything spotlessly and then spray it down with a solvent to see just how long the crack really is..there are online tutorials about using the crack finding solutions...

You could do basically the same thing with peened over 1/8 cast iron pipe plugs threaded into a crack and overlapping by about a third.....but the Lock-N-Stitch line offers some pretty good features to make badly cracked stuff stronger....
Owner of the world famous?? Pintojeep 3A and one yet to be named stock project 3A.
Based in central TX and upstate NY.

Offline F Bill

Re: Engine wall casting thickness.
« Reply #2 on: June 26, 2014, 02:22:47 PM »
You also may want to pull the head if you haven't already and check the head gasket surfaces for cracks.....the external crack may be one of many cracks caused by freezing...also check your distributor bore in the side of the block.. If you can pressurize it before pulling the head to see if anything shows up all the better..
Owner of the world famous?? Pintojeep 3A and one yet to be named stock project 3A.
Based in central TX and upstate NY.

Offline Carls_jeep

Re: Engine wall casting thickness.
« Reply #3 on: June 28, 2014, 02:01:35 PM »
You are entertaining a disaster. When a block freezes the pressure is as great on the outside as the inside. The bore wall could be cracked as bad or worse than the outside.

The only way to fix it is to tear the engine down completely and have it hot tanked and magnafluxed for cracks. If the bores are cracked it will have to be sleeved. If the outside is cracked it will have to be pinned or welded. You have no other choice than to do it once right or keep visiting it over and over.

Offline stony

Re: Engine wall casting thickness.
« Reply #4 on: June 29, 2014, 10:40:54 AM »
Yeah, I did run the engine after the crack, no coolant in the oil, so I think internally it is OK.  Yeah gotta get it taken apart to see what is going on.  Should just use the other block, but kinda look forward to a new challenge.
Terry
1949 CJ3A 11159 body 11225 engine 11140
On preservation vs. restoration:Roscoe Lee Brown "the Cowboys" when he met the whores on the trail:"Well, I have the inclination, but not the time”.

Offline Carls_jeep

Re: Engine wall casting thickness.
« Reply #5 on: June 29, 2014, 11:15:37 AM »
I agree, try repairing it. I saved my bad block to take to a friend in Springfield Mo so we can repair it and have fun.