Buying used engines

Brian T

Brian T

Well-known member
I have read often here that B engine blocks are prone to having cracks, my question is of all the A engines made were there any years that were more robust than others and less likely to have cracks other than user abuse.

I am thinking the 31 year engines would be better with improvements thru the years I am looking at building an engine, (undecided configuration or use) and would sooner not drag home unknowns that may become yard art.
I would much prefer finding a unmolested bare block as most everything will be replaced, repaired anyway, I hope the engine restorers here can understand my thinking.

Thanks Brian T.
 
Cracks can occur in any year block if the engine has overheated, metal fatigue or have suffered blunt force.

Having bought a few "Boat Anchors" in my time, I would only buy one contingent on having the block water/pressure tested and magnafluxed. Keep in mind some cracks are easily repaired but some can be very expensive and may not be worth repairing.

Watch out for the guy saying " it ran when I took it out of the car" and ask yourself (and him) why he took it out to begin with.
 
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were there any years that were more robust than others and less likely to have cracks other than user abuse
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MUCH discussed here are the so called "diamond" block. These were made in the period AFTER the Model A Ford for industrial uses such as gleaners, welders, and other uses. You can tell a diamond block by a small cast in "diamond" just above and to the left of the timing gear cover.

The engines themselves aren't that much different in any of the usual Model A sense - perhaps (someone confirm) they have the improved "B" style camshaft even though a A engine?

But the distinguishing feature of the diamond blocks is that Ford dramatically improved the "build quality" of the engines, perhaps capitalizing on the increased technical challenge of the V8? Wall sections tend to be heavier, cast surface finish is better, dimensions are generally more consistent.

And a better place to start doing the machine work - which also was improved.

Given a choice between a diamond and a regular engine - most choose the diamond.

Joe K
 
Any used engine I buy is done on the assumption it will need a crack or two repaired along with a full rebuild. I have never paid more than $65 for a used engine. I have had several diamond blocks and have one that still had standard pistons in it set back for future use. Although it is in need of a full rebuild, it is crack free and has never been bored. Rod
 
Watch out for the guy saying " it ran when I took it out of the car" and ask yourself (and him) why he took it out to begin with.

7 out of 10 times-hot rod....................
 
I would much prefer finding a unmolested bare block as most everything will be replaced, repaired anyway, I hope the engine restorers here can understand my thinking.

Wouldn't we all. Much nicer being the first one to rebuild it so there's no screw up to fix. The diamond block is preferable but no different as those crack as well as stock Model A's. only thing different is installed exhaust seats.

I get with someone who knows where they crack and have them show you what to look for because good blocks are drying up.
 
Diamond blocks had hard-seats in the exhausts, other than that not much difference. The later the A block, the better. Late blocks have thicker walls in some areas and are stronger in the main bearing web area. B blocks are fine if not cracked, look for cracks between the exhaust valve and the cylinder, especially on #2 & #3.
 
I have talked to another builder who says basically the same but his ratio is more like 1 in 10. What about us who want their original blocks rebuilt? There is an economic trade off between crack repair and ? I think that it may be useful to buy a used crack checker the next time I see one at Hershey.

Vic
 
CarlG said:
In a recent discussion with a prominent Model A Engine Builder indicated that he goes thru 8 blocks to find one good one.
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Thanks Carl:
Yes we just played out that senario: Customer bought a '29 pickup and wants engine rebuilt. First block has 17" of weld and is cracked.
Second block brought by customer; dirty says it's worn standard . The block after cleaning is cracked worse than first.
Customer finds third block is crack free but needs to be sleeved.

As I mentioned in the earlier post need to be familiar with the old iron and areas of crack and wear or else this senario could be repeated.
 
Here's a block I bought and didn't see this long crack until I got it home. It also has some cracks on the main bearing webs.
 

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There is a take out engine on eBay from a '29 phaeton. I asked a question about it since there is a link to Dreamwerks for comparison description/pricing. I asked if they were representing the engine as rebuilt/ or done by Mr. Rogers. The seller said no just comparison? There is a link in the posting showing the car being pulled into the garage before engine removal but you cant tell anything by the sound. Look at the price they are asking. They removed the engine to install a battery operated motor to use the car on broadway "Bullets over Broadway." I made an offer to buy the engine as a core but the seller said some Model A'er will step up to the plate. FYI

FORD MODEL A MOTOR RUNNING incl STARTER GENERATOR FLY-WHEEL 1928 1929 PHAETON
( 111607950580 )
 
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