Hello, I just purchased two 59-AB Flathead ford engines, one from a 1942 and the other from a 1946. I am new to flathead engines and trying to learn as much as I can, but I think that theses are 239s. Would I be able to put a mercury crankshaft with a 4in stroke in these, and what would I have to change with the pistons? Any help or information that you could give be about these engines would be greatly appreciated. Thank you!

 

You should be able to put the Merc crank into the early flathead.

 

What is the Merc crankshaft out of, a late model 8CM? I'd assume so. I don't think it's a simple swap, you'd need at a minimum all new rods, pistons. I would post it on the Ford Barn, Early V8 (1932-53) - The Ford Barn

What is your intended use?

 

I haven't purchased a Mercury crankshaft yet because I want to make sure that I can get the engines free, and would probably get an aftermarket one, same with the rods and pistons. Thank you both for the advice. If I only can get one running, I will probably put it in my 52 Ford F1. If I can get both of them running, I will probably use the other in a hot rod. Again, thank you both.

 

If both your blocks are 59 series, then neither one is 1942. A 4 inch crank will bolt into any 1939 and later full size (not 60 hp) flathead V8 block. The rods are the same for 3 3/4 and 4 inch strokes, except the weird French military setup. The piston pin height is changed to compensate for the longer stroke, again except for the French military setup. Depending on the rear main seal setup in you block you may need to purchase a rope seal holder. Here is a thread from the Ford Barn that will allow you to identify what blocks you have: Engine block I.D. pictures - The Ford Barn

 

If I'm not mistaken, the oil drilling on an 8CM-style crank would be different than those for a 59-series engine, due to the different types of rod bearings used? So I think the later rods need to be used. A 59-series crank that was welded and ground to create a 4" stroke could use the existing rods.

 

You are correct, the rods match the rod bearing style which matches the number of oil holes in the rod journals on the crankshaft. You can use the floating bearings and rods on the later crank, but you might have lower oil pressure.

I should have been more clear: all flathead V8 rods except a few weird french ones are the same length.

 

First, thank you all for your advice. I have been reading on this site and several others in the threads, I realize I should have done that first to help narrow down my questions. I have discovered that the gentleman that I purchased the trucks and engines from is not 100% sure of the year, which I will determine when I get them home sometime next week. I will also take a better look at the engines, one of which is out of the truck. After identifying them, I have to get them free. One of my mechanic friends recommended a 50/50 mix of acetone and synthetic transmission fluid. Do any of you have recommendations that you think would work better, as many people seem to have a certain thing that they like to use? Any advice is always welcome

 

If they are really rusty and stuck be prepared to use hammer and chisel, even a hole saw to cut through the tops of the pistons if neccesary. Fun times ahead.

 

I use Tap Magic or an equivalent tap cutting fluid. Seems to work well as a penetrating fluid since it is very thin.

I agree with jmadsen that you need to disassemble the engines in order to evaluate what you really have.

 

My brother who is into 41 Fords, tells me not to mount those older flathead V8s on an engine stand that holds the engine by the transmission end of the block. Apparently that end of the engine can break off. Sounds dangerous to me! I'm talking about the engines that have part of what we call a bell housing as an integral cast part of the block. He didn't tell me if there is good alternate way to hold it. Patrick

 

Absolutely true! You are supposed to use an adapter to hold them by the exhaust port holes:
http://www.ebay.com/itm/Flathead-Ford-59AB-8BA-engine-stand-adapter-ford-flathead-flatty-adaptor-/221489083271?pt=Motors_Car_Truck_Parts_Accessories&hash=item3391c73387&vxp=mtr

 

I have used 50/50 acetone/ATF for ever and swear by it. The Military has used it forever also.
That must mean something.

 

ALBUQ -1 and 41505379 are right about holding the earlier flathead V8s. My father was given this engine after it was broken during overhaul:

 

JB Weld???