A friend of mine drives a beautiful, all stock and unmolested 51 Shoebox Coupé that is giving him some trouble. He called me and said he had a fountain of coolant coming up from the carb. He let the engine cool down and limped it home, but of course it was running rough. This is his first old car and he does not know a lot, but is pretty decent in turning wrenches and pretty keen on learning a thing or two . I told him how to pull the heads and after work I went over to his place to take a look. I found several cracks in the deck going from head bolt threads to a water outlet, but these don't worry me. There is one crack going from #1 intake valve to the bore. The # 7 cyl surface has discolorations and is rust pitted. My guess is the crack goes down into the bore quite some... Couldnt get a good look with the engine still in the car, but I believe I could feel it. So , what do you think? Can a sleeve in #7 be the rescue for this block? I have not found any other severe cracks other than that, but of course we will have to inspect the block closely after it's been dissassembled and cleaned. What would be your approach to fix this one?
I don't think an informed decision can be made at this time. I'm afraid that engine will have to come out, be disassembled, and then tested to make sure. There are too many other places that it may be cracked that can't be seen. The fact that you say that "he said he had a fountain of coolant coming up from the carb" is ominous. I have run cracked blocks before and have never seen anything like that. Certainly it is an indication of something much more serious than you can see deep down in the bowels of the engine. Sorry. Your friend should get a head start start searching for another block now if he wants to keep running a flathead. Reasonably priced ones are scarce. Unfortunately, I see another SBC/SBF conversion coming.
Yep, cracks like that have been repaired with pins and sleeves, if it doesn't go too far into the port. But as Tubman says you'll need to do a complete investigation to see if it's any worse.
The headgaskets were both tight and undamaged .the intake runners and cylinders were full of water. My best guess is that one crack in the bore opened up enough to flood this cyl, pumping water into the intake and the exhaust( forgot to mention there was a huge cloud of white steam in his rearview mirror), supplying all other cylinders with coolant aswell and shooting the rest of it out the carb. I would not be surprised to find a bent rod or 2 the time we take the pan of. The car will have to sit for 2-3 weeks before I have Time to help Robert tow the 51 to my place and start dissassembling. I told him, the improvement and easy way out would be a chevy swap. But that car is so nice and untouched , I hope can fix this Block or find a better one... Thank you for your ideas ,guys! I also noticed the Engine has adjustable lifters, insert valve seats, a few different Style valves and no Ridge on top of the bores... Maybe it was rebuilt not too long ago...
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