This is my first flathead rebuild and I have a few thing I would like help on Please . Please ID this motor , and is there a trick on removing the head bolts, These have been on this motor for 40 years, the center head bolts I have been able to remove but the outer bolts are not moving ,, I was going to try 2 things , 1 heat, 2 I was going to drill down the center of the bolt to weaken them so the heads will snap off and only leave the studs , Then what am I in for trying to remove the heads. Any help would be great
It looks like a 59 Style block. There ahould be some numbers cast into the bell housing. I used an air impact wrench to take one apart. Worked pretty well and that particular motor had been sitting outside for a number of years.
First thing, take it off that engine stand because the bell housings have been known to crack and break when supported like that. Get a exhaust mounted stand adapter. Search on the HAMB will reveal lots of discussion on that and your other questions. Good luck with your project.
Distributor is 1941 thru 1944 model. Probably a 239 cu/in motor. When you get the heads off mesaure the bore probably 3-3/16". Don't think it's a 59A. Yep use an impact to remove or break off the bolts. Jim
I agree with Aldixie, looks like a 59 a/b. I'm curious why it is not on the housing. That always seemed like the one constant thing I was able to find when searching for a good block. And yeah, definately get an exahust mounted stand like tbird said. (Learned that from expeirnece via a friend of mine!) Good luck and keep us updated. The flatties are a lot of fun and despite various controversy, I think they are very cool. They are traditional, have that distinct sound and there are lots of cool stuff that can be done with them. Good luck brother.
The picture of the bell housing area makes it look earlier than 1946 to 48 59A block. Crab cap came into use around 1942 but could have been added to an even earlier 81A type block from 1939. You will need to measure the bore to find out if it is a 221 block or a 239 block. Getting those heads off will tell if you can. Getting frozen head bolts out is tough when it's not mounted in a vehicle. You will have to find some way to bolt it to a dead man framework of some sort so you can get the cheater pipe on your breakover bar. The bolts may break off while being twisted but I would try to get out as many as possible before grinding, drilling, or cutting the heads off. Machine shops will take broken bolts out for you but they will charge a pretty good labor fee for a bunch of them. They usually weld a washer to them them weld on a nut to turn them out. The heat will loosen them up but they have to be red hot before it will make much difference. It looks like the old motor set out in the weather for a while. It makes you wonder why they wouldn't try to preserve it better. May have been a reason for that. Broken block, water in the oil or something broke internally.
Many times an impact wrench will remove bolts that would twist off if you exerted enough torque to twist using a pull handle while trying to remove them, and they are rusted tight in the block. The impact has a hammering effect that helps free up the bolts. Just don't get carried away and use too big of an impact or you'll twist them off with it. Been a long time since I put a wrench on a flathead, but I'm thinking most all of them had casting numbers somewhere. Most likely it is a 3.187 bore as I can't imagine anybody putting those heads and manifold on an 85 hp block! The distributor is a '42'48 "crab" type. It's gonna take a lot of patience to break loose those head bolts as they are most likely corroded to the holes in the alum. heads as well as rusted in the block. One thing that might help is to remove the water pumps and make block off plates to seal off the openings there as well as anywhere else except the water necks on the heads. Then mix up half and half auto trans fluid and acetone, enough to fill the engine water jackets thru the head center outlets with the engine blocked up level. This mixture has been tested to be the most effective penetrant available. Let that soak a week or so, then try again. It should at least free up the head bolts in the block, and then you'll only have to overcome the head bolt to aluminum head corrosion!Ditto on the engine support on the stand. Dave
Give the head bolts a twist by hand to tighten a little first, then start loosening. And lots of Kroil...
Absolutely! Aero-Kroil is something a "tool-maker" buddy of mine turned me on to about 15 years ago...granted I'm young here at age 36m but that is one "tool" that has NEVER let me down!!! I swear by that stuff and use it all the time! Then get a breaker bar, and like AlbuqF-1 said, tighten a little, very little, then loosen, and go back and forth like that until they start to come loose.
Good advice on the 'Kroil' penetrating oil to hopefully help loosen things up. My recommendation is to NOT use any sort of breaker bar to loosen them. It looks like it has bolts and not studs, so this means that they were replaced AT LEAST once . . . which is a good thing (as they ALL came with studs). I would soak the heck out of them and use a 1/2" impact wrench. Make sure you use a 6-point socket as well. I've taken more of these apart than I can count and the impact wrench is by far the best bet. If it has bolts, then you'll have a much easier time getting the heads off than if it had studs. Studs are a real bitch with aluminum heads that have been sitting and corroding for 40 years! The engine looks to be a pre-59AB style motor. Hopefully it has the larger 3 3/16 bore, but my guess is that it has the 3 1/16 bore (just a guess). If it is the Merc version with the larger bore AND the block is good, then you'll have a much desired early 'keystone' block. It looks to have an Edmunds manifold - which works just fine. Can you turn it over or is it stuck? Hopefully it turns over with a breaker bar . . . makes dis-assembly a whole lot easier. If not, put a lot of the penetrating oil in the cylinders and intake ports a well . . . hopefully to loosen the reciprocating assembly up. Hopefully you have a big ass forged valve bar - as you'll be having fun with the valves/guides. You'll be cussing, swearing and get just plain mad at some point . . . welcome to the world of ancient Flatheads! When you get to the dis-assembly part, post pictures and ask questions - there are a few 'tricks' to taking these things apart that you may need to know. This is my fortune telling for today . . . hopefully it is a good block -- that is what is most important (regardless of the bore size!).
I'm building a '42 Merc 239 with the "keystone" block. Mine has the raised intake manifold mounting surface with the contours that follow the intake. That seems to be a pretty reliable indicator of a pre-war 239. I don't see that feature. The manifold mounting surface looks flat from head to head. Sort of hard to tell in the photos, so ain't sayin' for sure. Bob
Stating the obvious: It is a 38 to 48 motor since it has 24 studs (or bolts) and does not have the added water passage at the top of the water pumps that the 8BA (49-53) motors have. It has a 42-48 distributor with the 42-45 distributor cap on it. Things to check: If you can rest a pencil on the block behind the timing cover it is a pre-WW2 block. If the engine has bulges in the oil pan rail for freeze plugs it is 1940 or older. If the intake manifold sits on a slightly raised area it is a 41 or later block. Clean the block between the intake manifold and the passenger side head on the front half of the motor. If there is a 99 stamped there you have a prewar Mercury motor. Things to check / know on disassembly: 3 1/16 bore motors are sometime bored to 3 3/16 so even if you measure to the larger bore you might still have an 85 horse block. The valves are closer to the bore on prewar blocks which isn't a concern unless you want to put prewar heads on a postwar motor.
I think you are on the right track using heat before grabbing a cheater bar. Heat the aluminum around the bolts and heat the bolt head good and hot. let cool. With luck the expansion and contraction will have released the corroison. At least it always works for me. I don't use any magic oil. Just heat.
Heat the bolt heads cherry red then go have coffee. Should be cool when you get back. Then try the impact wrench.
A point about applying heat to the bolts and that is that amount of heat getting into the cylinder head is you are likely to upset the factory temper of the head. Basically that means they can soften and if you try to reuse them they may not hold the tension on the head bolt. In short you will have to throw the heads away.
Thanks to all. I will change the engine stand asap. also I will post the tear down pics as I go. I will start with filling the block with the trans oil mix , as it will be at least 2 weeks before I can get back working on it.
If those heads are not corroded past being used now, just step up for some good (ARP) hard washers. Do not get the hardware store hard washers that are case hardened on the surface only. Get the tool steel heat treated through kind that won't cup.
There is an adapter under that distributor so that it will mount to the three bolt timing cover. Looks like pre-59.
Ok I have a update. I soaked, heated,tightened, and all of the advice given and it took a little of everything to remove the heads, but they are off . it is a 3.187 bore with a 3.750 stroke . So i am saying it is a 40 or 41 ?. below is stamped on the passenger side on the intake surface heads still look good -- just hope the other side comes off easier
Looks great so far! The fact that you can turn it over is a great PLUS - makes taking the rest of it apart a whole lot easier. From the pictures, it looks good so far -- don't see any really rusted cylinders (sometimes an indication of a cracked block). The valley doesn't have a ton of sludge in it . . . so it has not ran that long. Also, the lifter bores are drilled and it looks to have adjustable lifters (can't quite tell in the picture) - so it has been rebuilt to some degree before. Now . . . onto the REAL fun . . . getting the damn valves out of it! Prepare to get brutal with it -- and if you need to break the heads off the valves (when they are up), no problem . . . you won't be using them again. Hopefully you have a big valve bar - as you'll need it to pull the guides down. If they are really stuck, then I knock or cut the valve head off and drive the guides out from the top. My buddy used a big ass bolt cutter to CUT the stems on his last teardown (in the valley area) . . . made it possible to pull the valve head and most of the stem out the top. I've used an air grinder and a cut-off wheel before as well. All sorts of 'tricks' to get the damn things apart! Then onto the hot-tank, magnaflux and sonic-testing phase. I highly recommend a sonic-test if you'll be boring it out to like 3 5/16 (which is what I'd do). Maybe you'll get lucky and they'll come out "easy" -- rarely works that way for me!
As clean as that looks, I don't think you will have a lot of drama with the valves. The last one I took apart looked 10 times as bad as that and I pulled it apart with hand tools. I used a BIG cheater bar for the head bolts and only broke 3 sockets before I used a air socket to finish the job. I also used a c-clamp type valve spring compressor and pulled the locks off and pulled the valves out of the guides with a pair of channel locks, so that is a thought if they are troublesome. I think the stamp may be from the previous rebuilder? I don't know a lot about the older ones...
If the valves and guides are stock it will have the mushroom end on the valve stem with the split valve guides, so they have to come out as a single unit. They made a tool that wrapped around the head of the valve so that you could drive the guide down to get the clip out. Then you could use a tool like the KD-918 to press the guide up and out. KD made another tool -- I think the KD-917 that was used to drive the clip out without the need to drive the guide down first. You can still find these tools on the evil auction site sometimes. They usually don't sell for too much money. Here is a reproduction of the old KD service bulletin it should describe things in more detail. http://www.ntractorclub.com/howtos/pdfs/K-D_valve_service_bulletin.pdf
Take care with them lifters. You will need to use them. Put a wire wheel on your grinder and clean the decks and look for cracks. Bolt hole to water hole ok they almost came that way. Valve to cyl. not good but can fix.
Have a look at this wed site.. http://www.enginebuildermag.com/Article/2016/removal_tricks_for_broken_ford_flathead_bolts.aspx The paraffin wax worked well for me.
Seems to be a '39-40 99 engine, 239, though it COULD be an 81A 221 bored out for the 99 pistons. Either is fine, except the smaller engine would only be able to take a little more bore. If outer wall of cylinder comes real close to the edge of the keystone water hole, which it looks like it does, it's a 99. It may have 99 stamped near front of manifold surface of block, will probably have the 2 freeze plugs on each pan rail.
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