Projects I'm 18 and building my first flathead 59AB+merc crank for my chopped 34 4 door sedan

Hi I'm Jesse I'm 18 and picked up a 8ba merc flatty for $100 last week for my birthday and thought that it would be cool to document the disassembly and rebuilding of the motor to learn the hamb better. I'm always looking to learn and any advice or knowledge would be much appreciated

 

Thats great Jesse. Lotsa love for flatheads on this forum. I'll be looking forward to pictures of your new engine. Good luck!

 

It's pretty crusty in the intake ports

 

Thank you!

 

Welcome to the H.A.M.B. Jesse!
Nice score for $100.



Sent from my iPhone using H.A.M.B.

 

Fords were 8BA, Mercurys were 8CM and trucks were 8RT
I drove a '46 Ford pickup with an 8BA, loads of fun.
Check out Van Pelt (and he is on the HAMB as well) http://www.vanpeltsales.com/FH_web/flathead_specs-90to125late.htm

 

Thank you for the info I probably should've guessed that from the 8CM on the heads lol

 

Heads can easily be swapped for those in desperate need of a HP " increase". Check for the throw of the crank out the elongated dimple on the crank.

 

Welcome young ‘un

 

welcome, the timing gear housing has a small indent near the base of the shaft... pilot...
if stock that is a 1949 only...

 

Thank you that's super useful I'm 90% sure it's stock

 

Just because it has Merc heads means nothing. Don't ask me how I know. If it has a Ford 3 3/4" crank the Merc heads will lower the compression. If you want to run stock heads find a set of EAB heads whether or not you have a Merc crank.

 

'49 Merc would have had wide belt pulleys. From what I can see in the photos the pumps are narrow belt but its hard to tell and pumps could have been changed over the years. Did it come with a bell housing? If it has a 1/2 bell sheet metal housing that's another indication of Merc but not a guarantee. Pull a head and measure the stroke. Then you'll know for sure.

 

I measured the depth the piston is in the motor and it is 4" is that enough information to tell?

 

Be sure to check all of the decks for cracks. Flatheads came with a national stock number for the cracks.

Sent from my SM-G973U using The H.A.M.B. mobile app

 

yea sounds like ya 4" crank in her thats worth 250 alone good score.
Take your time on disassembly and if no cracks you got yourself a real deal. What are your plans for it???

 

I want to do everything besides the machine work myself and put it in a traditional hotrod which might end up being a 1934 ford 4 door sedan that was chopped in the 50s that I picked up for $700

 

Bugger, you're really finding the deals! Way to go...

 

It's rough in the floor pans but the doors all close perfectly so it definitely would be a candidate for this motor eventually

 

The read two cylinders seem the roughest but it seems that there is no major pitting from what I can see and feel I'm going to try to get the oil pan pull tonight but it might carry over to tomorrow

 

I'll follow along.

 

Hmmm. I enlarged the picture and don't see even the "part number" cracks. You may have gotten lucky.

I wish you more luck with this.

 

Thank you for the good luck lol. I couldn't see any cracks either.

 

You may have to have it magnafluxed at the machine shop. Cracks may not be visible to the naked eye. Good luck and welcome.

 

Just so you know, "part number cracks" are the cracks between the middle head bolt hole and the water passage just below it between the #1 and #2 cylinders and #3 and #4 cylinders. They are considered to be harmless and are common in a lot of flathead blocks. I have found that if you get a block without them, it is practically guaranteed to be good. (Maybe I have just been lucky.) They are called "part number cracks" because they are so common that a few wags have suggested that they should have been assigned a "part number" by Ford.

In addition to having the block magna-fluxed, it should be pressure tested, which a lot of folks will say that will detect internal hidden cracks better than magna-fluxing.

 

Welcome and good luck !

 

Depending on how much of an over bore you plan on (if any) you might want to consider sonic testing the block in addition to the magniflux and pressure test. The machinist that did the work on my 8ba said based on his experience (extensive) and the mag test he didn't feel a pressure test was necessary. 10k on the rebuild and no issues so he was right

 

Hi Jesse,
Before you get too far along in your teardown, search "Mart" on here and check out his videos. He's resurrected a few flatheads, and has some good tips. His videos also show some problems and "oops" he's run into, along with hints on avoiding or worsening damage. He's a good narrator and time spent viewing his videos would be time well spent (and maybe less money spent). Good luck!

 

Hmm. In my experience, 1/8" (.125") overbore in an 8BA has never been a problem (and the pistons are the same price); Ford had the "core-shift" problem under control by then. I also believe that skipping the pressure test would be a mistake.

I also recommend "Mart"'s videos; the guy is a "practical" treasure. In the same vein, you might want to try "The Ford Barn"; website where things are a little more "flathead focused".

 

Thank you guys so much for all the advice I'll check all this stuff out tonight before I go to bed