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New Motor can't roll it.

Hawkdoc

Full Member
Joined
Sep 1, 2006
Messages
280
Ok, put in a new long block and had the tranny rebuilt. Has mild cam and flat top pistons. While trying to turn it to TDC, I flat out can't, and when I say can't, I mean to the point of flexing a 1/2 Inch breaker bar with a cheater pipe on the end. Plugs are out and Dizzy is out. Any ideas on where to start? had tranny in N and diff and N and every other tranny combo and yes I topped it off with fluids. It is a C4.

Thanks
Hawkdoc
 

Carl

Bronco Guru
Joined
Aug 8, 2006
Messages
1,035
Loc.
Aurora, IL
Have you checked your valve lash (clearance)? I'm no engine builder, but I think incorrect valve lash could cause an engine not to turn.
 

76Broncofromhell

Bronco Totalitarian
Joined
Jul 30, 2001
Messages
4,228
Loc.
Reno, NV
Did you install the torque converter on the transmission properly? If you put it in the same way you do with a clutch (as in install it attached to the engine rather than the transmission) it will lock the engine. That would be my guess as to your problems.
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,835
I am guessing engine is bound to the transmission as well.

Were you able to turn it over from underneith to attach the torque converter nuts? If installing the nuts is what you are trying to do can you move the torque converter away from the flexplate. Doesn't have to be a lot, just enough that the converter isn't bottomed out in the transmission. With the nuts off the converter should be a little loose on the flexplate, sort of rattles around.

If that isn't the problem, then did the engine try and turn over as you bolted the flex plate to it? The torque wrench should have exerted enough force on the crank to turn the motor over. If it didn't then the problem is in the motor.

Last wierd one I have run into. Flexplate counterweight bound up to the starter. Remove the starter and engine turns over. Install starte and engine turns over until the weight hits the starter. Flexplate went back the the engine balancer.
 
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Hawkdoc

Full Member
Joined
Sep 1, 2006
Messages
280
I will drop the starter and try and get the TQ convertor loose and see what happens. The engine did roll when I was torqueing flex plate to it. Thanks for the help.

Hawkdoc
 
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Hawkdoc

Full Member
Joined
Sep 1, 2006
Messages
280
76Broncofromhell said:
Did you install the torque converter on the transmission properly? If you put it in the same way you do with a clutch (as in install it attached to the engine rather than the transmission) it will lock the engine. That would be my guess as to your problems.

And to fix this problem, need to drop trans case and tranny and try again correct?
 

surfer-b

Contributor
Bronco Guru
Joined
Sep 7, 2006
Messages
2,972
76bronco nailed it, sounds like tq conv. to me, been down that road before.
 

wildbill

Old Bronco Guy
Joined
Jun 29, 2001
Messages
6,885
:p :p :p If the flywheel is on backward it will jam the motor also.:D :D :D Bill %) :cool: ;D
 

72Sport

Bronco Guru
Joined
Jul 8, 2002
Messages
2,954
Possible to have the bushing in the crank for a manual tranny. I did read it was a new long block.
 
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Hawkdoc

Full Member
Joined
Sep 1, 2006
Messages
280
wildbill said:
:p :p :p If the flywheel is on backward it will jam the motor also.:D :D :D Bill %) :cool: ;D
I did get that one right going back together. Will make sure while tearing all back down though.:mad:
 

Mherriford

Sr. Member
Joined
Oct 16, 2006
Messages
613
Loc.
Oregon City, OR
If the torqe converter is not completly installed than the motor will be bound up because the t conv. will be binding up in between the motor and tranny it can seem like it is in all the way but if you turn it it will slide in further this is just an idea, the valves could also bind the thing up had that happen to me once, in my younger more dumber daze
 
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