Cylinder crack

[Chuck Sea/Tac]

A friend of mine built an engine, .080" over. Has 600 miles on it and Sunday there was water in the oil and out the exhaust. Pulled the head and number three cylinder is cracked horizontally on the valve side, about 3 1/2" down.
There is a small crack repair between the exhaust valve and cylinder, but whether that was a warning sign of problems to come, I don't know. Anyone seen this before? I think his plan, at this junture is going to bore and sleeve that hole.

[Tom Wesenberg]

If the babbit is good, I'd sleeve it also. I don't ever recall seeing a cylinder cracked on the inside where the rings run. I have one, and have seen others with grooves from wrist pins, but I don't recall seeing any cracked inside walls. Have the block checked all over for other cracks. I have a block with cracks at the main bearing saddles and inside the valve chamber.

[Mark in MT]

I have seen several cracked from inside the valve port, across the valve seat and down the cylinder 2". Like Tom says, it is a fixable problem if the Babbitt is in good condition and the rest of the engine is good. Stop drill the crack at each end. Stitch the crack from end to end and dress the pins down inside the cylinder, sleeve the cylinder and then bore it to match the piston. A fair amount of work, but it will save another block.

[George Miller]

Any time you get a crack from the valve towards the cylinder you should put in a valve seat and a cylinder sleeve. Plus fix the crack. Put in a sleeve it will be fine. That is if they put the sleeve in right.

[Bob Bidonde]

I suspect that the cost of repairing the cracked block may equal or exceed the cost of rebuilding a another block with no cracks. I also would question the remaining life of the other cylinders.

There is no shortage of good Model A blocks, so I would have one rebuilt by a professional and experienced shop.

[George Miller]

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Originally Posted by Bob Bidonde

I suspect that the cost of repairing the cracked block may equal or exceed the cost of rebuilding a another block with no cracks. I also would question the remaining life of the other cylinders.

There is no shortage of good Model A blocks, so I would have one rebuilt by a professional and experienced shop.

I have put sleeves in while the engine was in the car in the old days. It is not a big deal. If you are going to rebuild the the engine you might be better off to find another engine.

In my Sport coupe I had to put in two sleeves. It was the engine the car was built with. I wanted to keep the original engine. To me that means something. That was 22,000 miles ago.

[hardtimes]

Originally Posted by George Miller

I have put sleeves in while the engine was in the car in the old days. It is not a big deal. If you are going to rebuild the the engine you might be better off to find another engine.

In my Sport coupe I had to put in two sleeves. It was the engine the car was built with. I wanted to keep the original engine. To me that means something. That was 22,000 miles ago.

Hey George,
'it is no big deal'....ha, YOU are a hoot !
No big deal, for a guy who builds his own OHV Head and engine for pieces of metal and stuff !!

BTW..Have I missed THE engine running video ?

[George Miller]

Originally Posted by hardtimes

Hey George,
'it is no big deal'....ha, YOU are a hoot !
No big deal, for a guy who builds his own OHV Head and engine for pieces of metal and stuff !!

BTW..Have I missed THE engine running video ?

No it only ran for a short time. I think I have a camshaft problem. But I was running out of time. The hill climb will be end of next week. So I put the head on one of my other engines, that ran strong before. So it will be a spell before I get back on it, maybe next winter.

[BILL WILLIAMSON]

"THERE IS NO SHORTAGE OF GOOD MODEL A BLOCKS"!!!---HA-HA-HA-HA!
Buster T.

[CarlG]

There may be a lot of blocks out there, but my engine builder tells me that he throws away 8 blocks just to find one good one.

Seems like I remember Steve from Berts saying on this forum that he just sent several tons of blocks that were no good to the scrap dealer.

Go, Tod, Go!

[Mikeinnj]

Originally Posted by CarlG

There may be a lot of blocks out there, but my engine builder tells me that he throws away 8 blocks just to find one good one.

Seems like I remember Steve from Berts saying on this forum that he just sent several tons of blocks that were no good to the scrap dealer.

Go, Tod, Go!

Can't wait until Tod is banging out the new blocks.
No more trying to make poop from Shinola.