8BA Flathead rebuild

K

kccos

Junior Member
First off i have NEVER messed with a Flathead before. So all of this is new to me. Well I have had this 49 flathead in the barn for about 4 years and I have the same good running motor in my shoebox. So for the fun of it and to get to know these motors better I wanted to tear one apart and try to rebuild one myself. Lets see what kind of damage I can do.
Here is what I am starting with. I think it is a 1949 8BA. It is stuck. Before I try to get it free I wanted to pull the heads to check and see if there was any visible cracks our anything majorly bad with the block that I can see.

My first question is. As you can see one valve is stuck open and I think one is stuck open on the other side. Is this normal? My second question is once I get the other head off and if I see no cracks and I keep on going with this block. Should I just bolt the head back on and fill them up with ****** fluid or what not and let it set a few days to try and get the motor to break loose.

Thanks

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So I started pulling stuff off.
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When I pulled the intake off I found a nice little stash of corn and grain.
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Pulled the gasket off and found a nice mice nest.
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R.I.P.
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vally shot
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Got the pass side head off and I only broke one bolt off.
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You will find valves open, because they are on the cam. They are supposed to be open. Leave the heads off and repeatedly soak with a good penetrant oil. PB blaster is good stuff, so is Kroil. Tap on the piston tops occasionally, let soak. Try to rotate the crank, soak, keep trying. Be patient. How much ridge do you have at the cylinder tops? Cylinders very rusted?
 
OK well I got the other head off last night and BAM! I was hit with this. I am sure someone will let me know forsure if this can be fixed. One of the valve areas on this side looks REAL bad and it looks like the valves are rusted in thier pretty damn good. Not sure if a machine shop could fix this our not? Also we miked one of the cylinders and it looks liked it has already been bored out 30 or 40 over already. So not sure if I should keep on with this block??? Hit me with the bad news. I can take it!!

YUMMY!!!
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I've seen a lot of mice in flatheads. They go right in through any opening big enough. If your cylinders are badly rusted, even ATF & acetone might not do any good. I've cut more than a few pistons apart to keep from damaging the cylinder walls any further than they already are. It's worth a try if not too badly rusted. Stuck valves are a given if a motor has set up too long. A flathead's cylinder walls can be bored a way lot farther than most modern motors can and a really bad one can be individually sleeved to make it work again.

There are a lot of post on this board about disassembly of crusty flatheads so you might do a few searches for more info.
 
Use the 5o/50 mix od acetone and atf, it really works. While thats working it's way through the stuck parts. Get an old motors manual of the mid 50's. Might be able to borrow one and copy the pages. And of course you have use guys.
 
Kccos, your first statement say's it all. Go getcha Ol' Ron and JWL's Flathead book's.

Get you some education from the folk's that have lived it and come out of the darkness son:D

Don't wanna hear about any damage:eek:
 
"R.I.P. valley shot." How so? Pictures are not showing. If the block is not cracked it's worth saving. X2 on 39portlander's comment. Get those two books. Check this out also. http://www.flatheadv8.org/v8manual.pdf This is a reconditioning manual for flatheads through the 59 series(pre 48). It will give you an idea what is involved although the 8BA is a little different.
 
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Well I got the oil pan off and the motor flipped over to check out the oil pan rails for cracks. I got the gasket off and cleaned the rails up good with a wire brush and I looked it over real good and did not see any cracks. Got the two back pistons out number 4 and 8. They came out real easy. All the rings where intact. No scoring on the piston our cylinders. I have the really bad piston soaking but I doubt it will help. I will probably have to drill and hammer that one out. There was really not that much sludge in the bottom of the pan either.

Should I take the cam out because I know I have a few stuck valves as well? That way when I get the stuck piston out I can turn the crank to get the rest of the pistons out.

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KCCOS;
Go back about 3 pages of forum to "School Me On Flatheads. There are about 4 pages of correspondance that is very good about crusty old flatheads and disassembly of same. It should provide you with some insight as to what you are facing.
 
Chris Nelson said:
KCCOS;
Go back about 3 pages of forum to "School Me On Flatheads. There are about 4 pages of correspondance that is very good about crusty old flatheads and disassembly of same. It should provide you with some insight as to what you are facing.
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Ok thank you. I will check it out.
 
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