How to tell if a motor is buildable

Big Bore

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Following on from my friends nightmare I thought I'd get some input on things to look for when examining engine parts to see if they are even worth having magnafluxed.

So during a visual inspection there are a few things I know I will look for based on what I've learned over the years. I'm sure things are missing so feel free to add to the list. I might copy and paste them into this post for future reference.

Look for cracks in block at webs and in cylinder.

Check pistons for cracks.

Check cylinder walls for scoring that is too deep to be machined out.

Check crank journals for scuff marks.

If pistons are still in block check protrusion (not sure what that number is) which gives an indication of rod straightness.

Check valve seats for cracks and and check heads for cracks at exhaust valve openings and exhaust manifold ports.
 

Arisley

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You can compare piston height's. If there is a difference you have bent rods. If they are all the same, they are either straight or all bent the same amount.
 

bpcheramie

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You can compare piston height's. If there is a difference you have bent rods. If they are all the same, they are either straight or all bent the same amount.


Have u ever seen 8 bent rods? It is kinda funny when u are trying to check them and they are all bent....
 

Arisley

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Have u ever seen 8 bent rods? It is kinda funny when u are trying to check them and they are all bent....


All the same too.

No, I cannot say I have ever seen a motor with eigh bent rods. Seen quite a few with one bent and one or two broken. But those, you didn't even try to save anything from the motor. You had to actually remove them in pieces.
 

bpcheramie

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Yea the last set we pulled from snow white was like that and the only way we knew they were bent was because the pistons were so to speak rocking in the bore. Most were about the same on protruding from the block. Only one was really bad.

So point is check them make sure they are in spec then look at the side load on the cylinder wall..... If real tight on one side you may have a bent rod.....
 

StockCar#10

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i would "FROM PERSONAL EXPERIENCE" check your main web casting rise... my block cracked on stageII's termies and a 38r... needless to say wen i got the engine on the ground and saw more than 3/16" rise all the way up the mains i was pretty well set on not playing with another 7.3 with out knowing what the block looks like...
 

bpcheramie

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i would "FROM PERSONAL EXPERIENCE" check your main web casting rise... my block cracked on stageII's termies and a 38r... needless to say wen i got the engine on the ground and saw more than 3/16" rise all the way up the mains i was pretty well set on not playing with another 7.3 with out knowing what the block looks like...

One word for you OUCH......
 

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