Cracked Block Quastion

Kohnke Rebabbitting said:
About 1, out of 2 or 3 Model A blocks are cracked. We have fixed them all, except 1 in the past 47 years, and none have leaked.

And that is a lot of engines of all kinds.

That doesn't mean that you turn your local black smith loose with a welder!
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Of course not, there are sound, time proven methods to repair just about everything that can be repaired. Replacing something just because it is broken, in my opinion, is a waste.
 
KMeredith87 said:
I have finally gotten the chance to pull the engine out of my '30 pick up and have now found a crack in the #3 exhaust valve. It is hard to see in the picture but the crack goes from the valve seat through into the cylinder wall. Would this block be worth trying to save or is it something that would make a nice table? I have only done a visual inspection and have not had it magnafluxed yet but the crack can be seen without that being accomplished. If the block is not salvageable where is the best place to pick up an engine without having to have a core?
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Yes this crack and seat can be repaired. Before you take it to the local shop make sure that they aren't going to use" Crazy glue,silly putty/JB weld or most recently lead filling".

Your picture represents why engines need valve seats. Pounded out.

Number two and three exhaust seat is a common area for Model A and T engines to crack. They can be easily repaired if the machine shop knows how.! There's no need to find a replacement block as we've been fixing these now for years.
What's to say the replacement block is crack free; it may be worse.?
http://www.jandm-machine.com/metalStitching.html
 

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Well, I say, Thank God! that new blocks are being developed! Terry Burtz and the other guy, Todd, I think. When I was fooling around with Ford 8N tractors, The successor to Central Tractor, in Iowa (Can't recall the name now) was producing NEW engines and blocks, In China, for around $2500. I have no idea how they worked or lasted. That was in the late nineties, early two thousands, so these new engines have a little track record. But it can be done!
I, Personally think every model A engine is doomed to internal stress cracks. With 30% to 50% of used blocks lasting 80+ years and then a virtual epidemic of cracking. The castings are timed out! They probably could be saved with some exotic heat treating, but I don't know!
Terry
 
ronn said:
if you can live with it Mike-no problem
so when you sell your car, do you tell the "new" buyer about all of the cracks in the engine that were repaired "correctly"..........?

just a moral question for thought
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I don't see the moral issue regarding this thread. Pinning or stitching the crack has been done for years and accepted as a good technic for the repair. What is there to cover up?

I am more trusting of the seller that tells me that the block has been stitched, that rust repair panels have been used, and that there is body filler underneath the shiny paint. I am skeptical of those that tell me the block is not cracked, the tin is original and no body filler. ;)

Everyone has to determined where they are comfortable with the parts in their car but hopefully the parts that are determined to not be worth fixing can be passed onto someone else that will appreciate them.

Neal
 
Thanks for the opinions guys. As for the engine matching the truck, not 100% but I do know that the engine number is the same number it is titled as. As for whether the engine was running, it was and was running surprisingly well until it wasn't. Took it apart, every babbitt is completely wrecked and the crank snapped in half at the number four journal and I didn't see anything coming prior to this happening. Now with that, I've learned I should have been checking bearing clearance every so often which I was not and did not know I was supposed to, too used to modern cars and jets I guess. However, there was less than 8000 miles on this engine since it was rebuilt so I don't know. I did drop the block off at the machine shop today to have it cleaned and magnafluxed for any other cracks. I'll keep you guys posted on what I find and decide to do. I may just find another running engine and rebuild this one at a later date, we will see.
 

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JJ Cunningham: Hopefully you have had good luck in securing a block and engine rebuild for your car?
Since you've had so many problems with cracks from the rebuilder.

This is how we do them rather than soldered joint, we leave to the plumbers!
We even had one like yours that the JB weld,solder and an attempt to do stitching. Fortunately for the customer he came to us.
 

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Bruce said:
How do you repair a crack that extends down 1 1/2 " into the intake valve hole?
The top has been stitched.
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Pre heat the block slowly until hot then weld with Nickel Rod Like softweld99Ni or softweld55Ni then cool over 3-4 days in the oven or sand box
 
"Do you replace the body parts with new or have the repaired by reforming and welding?"

body parts don't propel me down the road Mike....

I see many on here will repair anything and I guess that's a good thing. You all have far more experience on engines then I do. I still won't buy a stitched and pinned engine and wish Ryan had left the response to my original question on here. It gave an opposing view of a guy who was screwed at purchase. His stitched and pinned engine fell apart, but I guess we don't want to hear about them apples in fairness, just what we want to hear is what we hear.....
 
Bruce said:
How do you repair a crack that extends down 1 1/2 " into the intake valve hole?
The top has been stitched.
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Bruce: If you refer back to my post#25 you'll see the same repair you're enquiring about. We machine the valve seat area out for a new seat repair the crack through stitching and good as new again. No welding. Ever.
 
ronn said:
"Do you replace the body parts with new or have the repaired by reforming and welding?"

body parts don't propel me down the road Mike....

I see many on here will repair anything and I guess that's a good thing. You all have far more experience on engines then I do. I still won't buy a stitched and pinned engine and wish Ryan had left the response to my original question on here. It gave an opposing view of a guy who was screwed at purchase. His stitched and pinned engine fell apart, but I guess we don't want to hear about them apples in fairness, just what we want to hear is what we hear.....
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I wish he did also as I only remember a block that was soldered not one that was stitched failing.
 
KMeredith87 said:
Thanks for the opinions guys. As for the engine matching the truck, not 100% but I do know that the engine number is the same number it is titled as. As for whether the engine was running, it was and was running surprisingly well until it wasn't. Took it apart, every babbitt is completely wrecked and the crank snapped in half at the number four journal and I didn't see anything coming prior to this happening. Now with that, I've learned I should have been checking bearing clearance every so often which I was not and did not know I was supposed to, too used to modern cars and jets I guess. However, there was less than 8000 miles on this engine since it was rebuilt so I don't know. I did drop the block off at the machine shop today to have it cleaned and magnafluxed for any other cracks. I'll keep you guys posted on what I find and decide to do. I may just find another running engine and rebuild this one at a later date, we will see.
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Wow, that is a mess, sorry to learn of you having so severe and many problems with this 'rebuild' :(!
As I look at that crank, am wondering: What size main/rod journals was the crank ? Doesn't 'look' drilled for pressure...was it ? Looks awful small journals, usually all cranks (that were not drilled) I've seen snap at rear main ?
 
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