Engine Motor problem
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Engine Motor problem
- Thread starter MacD1
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CJ
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- '72 CJ5, 401, T18, D20, D44, D30
'82 CJ8, 258, D300, AMC20, D30
1st off, a 73 AMC 304 is a non interfere engine. What that means that no matter where the cam, valves or pistons are in rotation with each each other that it cannot cause any valve train damage via piston interference. Its not physically possible on a stock engine.
Without interference, the pushrods should not be bent.
We need to do more research.
What does a compression test show for each cylinder?
Is the engine stock?
How was your oil pressure?
Most important, what two pushrods?
Just don't go replacing parts nonchalantly without diagnosing the issue.
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- 85 CJ7 4.2L 258 .040 over, T-5 trans, dana 300, dana 30 front 3.23 and lock right locker, rear amc 20 3.23 one piece axle shafts traclock
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Couldn't have said it better. Is your timing set correctly? How many degree before TDC?
CJ
Admin
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- 24,394
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- 881
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- '72 CJ5, 401, T18, D20, D44, D30
'82 CJ8, 258, D300, AMC20, D30
Well 
! Just went through my notes and it looks like some 304s were interference!
Let's start with which pushrods were bent on which cylinders? The reason is to drill down by firing order.
You did say the valves were ok. So you pulled both heads and inspected the valves and pistons? That is a lot of work.
Since you pulled the heads, which ones showed piston contact?
The most telling test is what does the compression check show? If the do not show good compression, then you do not have a cam problem (which I highly doubt) but a timing issue or something still bent.
Jumping a tooth due to a old timing chain won't hurt the cam.
! Just went through my notes and it looks like some 304s were interference!Let's start with which pushrods were bent on which cylinders? The reason is to drill down by firing order.
You did say the valves were ok. So you pulled both heads and inspected the valves and pistons? That is a lot of work.
Since you pulled the heads, which ones showed piston contact?
The most telling test is what does the compression check show? If the do not show good compression, then you do not have a cam problem (which I highly doubt) but a timing issue or something still bent.
Jumping a tooth due to a old timing chain won't hurt the cam.
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