What to look for on a preliminary block inspection?

[Ken Henry]

I'm planning to look at a 51 truck engine on Wednesday and am hoping for suggestions on what to watch out for. This would be to use as a core for building up a bigger displacement engine for my 51 tudor, which has a nice running 8BA in it already.


What I know is that the engine was pulled from a truck years ago and the current owner got it running briefly though two cylinders were dead. It has been stored in a warehouse since then. I have the go ahead to remove the heads to look for obvious cracks, but don't know what kind are definite deal breakers vs repairable.


Engine is about an hour away in Buffalo, NY.



Thanks for any input! Ken

[Kilohertz]

What size truck is it? F1, 2, 3 etc? You might get lucky and find it already has a larger than 239 engine. EAB heads are the highest stock compression heads, I think the EAC came out around 1950 one the Merc engines and are a little larger combustion chamber.

I have read that the cracks commonly found between the studs are repairable with new inserts, the cracks between the valves would be more difficult to repair. I found a youtube video a few weeks ago that explained a lot about the blocks and what to look for...I'll try to find it and share the link.

I'm still new to flatheads so my words are not gospel...but I'm learning lots from everyone here.

Cheers


https://www.youtube.com/watch?v=T_9DsWDGwiY


https://www.youtube.com/watch?v=zuqBPkUILag

[Ken Henry]

Should have specified, it is a 239 8ba style engine. Not sure what heads are on it now, maybe 7RT if they are stock?

[19Fordy]

Check for stripped threads and if it's missing the small parts that are hard to find.
If so, it has been stripped for a reason. Pull the intake and look inside for adjustable lifters.
Also, see if it's frozen.

[drolston]

Pull the pan and carefully check the block pan rail for cracks. It water has frozen in the block, that is where it will show up. Generally not fixable.

[tubman]

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I would have to disagree with the statement "You might get lucky and find it already has a larger than 239 engine". If it is a large Ford truck, it would have the 337 Lincoln flathead, which, while kinda neat, is one heavy sumbitch. They are certainly not a good match for a '51 Ford. When I was in high school, two guys I knew put one in a '53 Ford. As soon as they set it in, it put the suspension right down on the stops. When they finally got it running, it was hard to steer, handled like a safe in a wheelbarrow, and was slower than a good running stocker. All and all, a total mismatch.

Although one may have been swapped in, Ford trucks never came from the factory with the 255 ci Mercury.

Every flathead that I have had that had no "part number" cracks turned out to be good. It's a good "quick and dirty" indicator.

[19Fordy]

tubman makes a great point. 337 is a boat anchor but, it sounds good in the song.

[Zeke3]

Originally Posted by tubman

handled like a safe in a wheelbarrow,

That one got me.

[Ken Henry]

Thanks! By part number cracks are you referring to the ones in the deck between the head bolt holes and coolant passages? What about cracks between the cylinder bore and valve seat? Not sure if it will be an option to pull the oil pan to check the rails but will give it try... Ken

[Tim Ayers]

If the heads are off, bring a wire brush. Better yet, a cupped wire wheel that you can put in a cordless drill. Bring some brake cleaner and hit the areas around the valves and hit them with the brush. Most of the times, READ: NOT ALL THE TIME, you can see a crack from the valve seat to the cylinder after cleaning if it's there.

Most important tool to bring with you is a super bright LED flashlight. That will also help you see any cracks, damage, issues etc. that are obvious. If it passes these tests, try to get the seller to agree to some type of guarantee that the block will past both a pressure test and mag testing.

If not, do not offer a lot of money for the motor. Tear down is a dirty and hard job. Only serves to give you heart break if it turns out to be no good. No reason to add insult to injury by paying an arm and leg for a possible boat anchor

[Aarongriffey]

The last 8ba I bought had foot long cracks between the oil pan and exhaust manifolds on each side. Did see them until it was hot tanked.
The two before that had cracks in the valve seats to the bore.
I forget now, why is it that so many guys put Chevy engines in these old cars?
So far I have resisted the urge.

[Ziggster]

Lots of good advice. It is a crap shoot, so good luck. Also, bring a helper or two if you decide to purchase it unless you already have a handy way to move it. Also, the coming storm may have a surprise for you tomorrow or Wed, so be prepared accordingly. Bring lots of rags/ shop towels, hand cleaner, degreaser, etc, and a garbage bag to stuff everything into, and maybe some boxes if you know there are already loose parts. A couple of ratchet straps can also be useful to secure it. Also check around to see what other stuff they may have.

[Ken Henry]

Right, need to keep an eye on the weather!! I plan to look it over as well as possible on Wednesday and leave a deposit if it looks worth pursuing.

[Yoyodyne]

I've been through 6 junk engines trying to find 1 good block, and I've developed a new strategy because of that. Next one I'm going to leave the heads on a pressure test it by capping the water inlet and outlet, with a plate over the water pump mount if the pumps are off, and pressurize it through the drain fitting hole. Only if is seems ok that way will I take the heads off and look further. I disassembled, hot tanked and magnafluxed all those motors that were assured to be good, and every one had fatal cracks that weren't found until after all that work. And the last one that seemed good in magnaflux still had one show up when pressure tested afterward.
Pay a maximum of $200 for any engine that can't be heard running and take it home, hoping to recover the $200 in parts sales if the block is junk, and write off the time and expense you go to to find out if it's junk or not as a 50/50 gamble.
I recently saw an ad for a pressure test kit offered to mechanics (dealers?) long ago to pressure test engines traded in as cores before disassembly, and though WOW why didn't I think of that sooner! START with the pressure test! genius!

[tubman]

Here's a gizmo I made to do a preliminary pressure test on 8BA's. The vinyl cap and hose clamp can be put over the hose outlet on the water pump. If the pumps have good seals, it can even be done in the vehicle. If the seals are bad, or if the engine is accessible, the plate bolts over the water pump opening. The smaller plate bolts on in place of the thermostat housing. It has a pressure gauge and Schrader valve mounted on it. I give it about 10 lbs of air and wait and watch.

[Ken Henry]

Wow! 6 blocks must be extremely disheartening! Sorry to hear it. This guy is asking 400 and says he had it running briefly, and no coolant in the oil, but I suppose even a cracked block might pass that test?? Not sure of my options other than hoping for beginners luck!!

[VeryTangled]

Well, Let's hope it's really worth 400. Honestly if it's good it's worth more.

But the 400 is all a crapshoot until you know it can be used for your desired purpose.

Even if you see it running it can still be cracked. Cracked blocks run quite well, sometimes for a crazy long time.

I think the 200 range is safer for you.

But when my Dad did a similar deal about a decade ago the negotiation was $100 now (after all the 'I trust you' and 'it ran' and 'you're good'), and $400 more when it proves usable.

Thankfully we hit on the first try and were happy to be able to get a tested workable piece for $500 (without the testing and stripping). The seller was a gentleman.

This is the block that went to Mark M. and is now in my '35.

[Ken Henry]

So here's what I found upon pulling the heads. You can click the pictures to bring up higher resolution versions. At least one combustion chamber has a crack between the valve seat and cylinder bore:
E0E709EF-8539-4147-92F0-CD684E29685B by kenhenry_06268, on Flickr



Another had water in it at some point and is badly corroded:
E8D27A4E-643E-47F8-A5E9-1756F6819074 by kenhenry_06268, on Flickr



Finally, there is one with a dislodged valve seat.

A0B5F606-0034-4200-9412-B16601FD4796 by kenhenry_06268, on Flickr


And of course some nice looking combustion chambers:
00794704-EE49-4F11-BB8F-3EC4E6AF194D by kenhenry_06268, on Flickr



I did not check the pan rails as I ran out of time and the engine was not a stand, but I'm guessing this is a 'pass' or at least not worth $400. Thanks for any input! Ken

[JSeery]

Looks a little rough!

[Ziggster]

Too bad. That crack must have something to do with the displaced valve seat. What would have caused that? Good luck in your search!