Help with an 8BA Flathead V8

57ChevyWagonMan

57ChevyWagonMan

Member
I just got a flat head that has been stored for many years in a barn. I was told it came from a state highway maintenance dump truck. I was tolt the reason it was taken out of service was a cracked head. One head was held on with only one bolt and I was told that was almost certainly the suspect head. After a quick inspection I see no signs of cracks in the head or any in the deck that amount to anything. My guess at this point is it was simply a bad gasket. I want to hear from the experts. What is good, bad, and repairable on these blocks. I am planing a mild rebuild to power my 1930 Model A 2 door sedan.

Thanks!

Mike:cool:
 
Pictures are our friend. Please post some!

What is the condition of the motor? Is the engine stuck? How do the bores look? What is the bore diameter? Etc?
 
The motor is stuck from siting. My guess it has been up in the barn for about 30 years. I have the cylinders soaking in oil and I am hoping it will break loose with a bit of persuasion. I quickly checked the bore with a caliper (I know not the correct way) I got 2.225". If what I have seen is correct this implies that the motor has been bored. I only have one head off at the moment and the exposed cylinders show little to no ridge. I don't believe I will need a ridge cutter to remove the pistons.
 
57ChevyWagonMan said:
The motor is stuck from siting. My guess it has been up in the barn for about 30 years. I have the cylinders soaking in oil and I am hoping it will break loose with a bit of persuasion. I quickly checked the bore with a caliper (I know not the correct way) I got 2.225". If what I have seen is correct this implies that the motor has been bored. I only have one head off at the moment and the exposed cylinders show little to no ridge. I don't believe I will need a ridge cutter to remove the pistons.
Click to expand...
3.2275 would be .040 overbore so you pretty close with your caliper. clean the top of a piston and see of if .040 is stamped in. Walt
 
Good news! I got her broke loose today. The pistons are domed. If I am at .040 over with a domed piston how much horse power is that worth? Did the 8BA have aluminum or iron pistons originally?
 
Post war engines all had aluminum domed pistons. Prewar from the late 30s were also domed aluminum but early to mid 30s V8s went back and forth from steel pistons to aluminum and earlies had flat tops.

Does your engine have a half a bell housing on the back of the block or is it one of the later 8BA type blocks with no bell on the back?

Kerby
 
I was asked for photos early on in the thread. Sorry it took so long but here they are.

DSCF3306.jpg


DSCF3307.jpg


DSCF3308.jpg


DSCF3309.jpg


DSCF3310.jpg


Hope you enjoy!:cool:
 
So far with only one head off things look great! I still want to pressure wash the thing cleaned and tear it down to check out the rest of the block.

Mike :cool:
 
Stick a long screwdriver in the lower water passages down to the bottom. My engine despite numerous flushings, reverse flushings, & chemicals had over 1" deep mud in the bottom. Pull the water pump off the front & blast the hose in the head surface holes & dig with the screwdriver.
Water pump has hidden bolt inside the inlet, usually rusty and had to use 14 or 13 mm 6 point to get it sometimes.
It looks like intakes have inserts also, my understanding cars had only exhaust inserts truck motors all seats were replaceable, NAPA has them.
Truck exhaust valve clearance in my motors manual says .018, don't do it, we did and and rattled so bad, a month later we swapped in adjustables set them 12-13.
That's a BIG generator, like a truck. Some guy up north of you name of Becker modifys alternators to fit the generator mount & use that pulley, has setups for all the flathead configurations. I got one at the flea market, just swapped my old generator parts for the ones he needed and had one ready to bolt on 1 wire. No volt reg. to mount, heavy harness from motor to firewall, 6volt PITA unless you are doing a restoration.
 

Attachments

  • DSC02517 (2).JPG
    DSC02517 (2).JPG
    62.4 KB · Views: 52
That's definitely an old truck motor. The generator looks like a high output type. It also looks like it has the big 11 inch clutch.

Kerby
 
I have a question about the oil filter mounting. $9 mounted with the head bolts and later heads had bosses for the filter to bolt to. Is the bracket on there something they did on earlier heads or did someone fabricate it for a later filter?
 
Man I like that generator. If you want to get rid of it, put me first on the list!

The early 8BAs, 49s I think, had the head bolt mounted oil filter canisters. The later 8BAs had bosses cast in the head for the filter in the picture. I think someone made the adapter in the picture.
 
I could be wrong but,I don't think it's a truck motor,the heads say 8BA not 8RT ,also I think the truck motors have a longer oil fill tube.Just my 2 cents.
 
The generator is a 12 Volt positive earth Heavy Duty generator for trucks.
It starts charging at low rpm.

And its a Ford original Lowering kit ;-) Since its so heavy L.O.L
 

Attachments

  • 49 truck stor generator II.jpg
    49 truck stor generator II.jpg
    20.1 KB · Views: 26
  • 49 truck stor generator.jpg
    49 truck stor generator.jpg
    58.2 KB · Views: 26
Last edited:
As far as that generator goes I have no intentions of using it. My rod is going to be 12V negative ground. Make me an offer, I am open to trades. I need a bell housing and a few other parts.

Yesterday I got most of the grime pressure washed off. Apparently someone was cleaning out the spray paint cabinet. The block is blue the bell housing and generator bracket are red, the heads orange, and the intake, water pumps and timing cover are green. (what a mess)

I got the other head off today and the gasket was blown. No visible cracks yet. However since the motor turns over easily but I cant get a full rotation out of it I am now suspecting it has one bent con rod. likely on the number 3 cylinder. My guess is the truck sat with a leaky head gasket and an attempt was made to start it on the compression stroke of number 3 with antifreeze in the cylinder. It likely hydraulic locked the cylinder bending the rod. I had a 350 Chevy once with a very similar problem.

Mike :cool:
 
57ChevyWagonMan said:
. However since the motor turns over easily but I cant get a full rotation out of it I am now suspecting it has one bent con rod. likely on the number 3 cylinder. My guess is the truck sat with a leaky head gasket and an attempt was made to start it on the compression stroke of number 3 with antifreeze in the cylinder. It likely hydraulic locked the cylinder bending the rod. I had a 350 Chevy once with a very similar problem.

Mike :cool:
Click to expand...

...or a valve is still hung up and the cam is stopping the crank. Truck pan will have the cleanout plate so you can get the pickup screen off for cleaning. Maybe you can see something from there
 
You must log in or register to reply here.
Back
Top