Rear Main Seal Done, KNOCKING NOISE

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AustinDube

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Hey, so i just did my rear main seal 2 piece, hearing a knocking noise when its turning over. I torqued the bolts of the rear main cap at 75 ft lbs but just put the bolts in dry. Is it possible the bolts require loctite and could have loosened up? Right now I am assuming its the crank rubbing against the oil pump pickup since i changed that too, what do you guys think?
 

74 Shortbed

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If the bolts and block are dry you didn't get a proper torque, NO loc-tite just oil they will not come loose. Odds are the pickup isn't installed right if you didn't have this noise before, drop the pan and have someone rotate the engine by hand while you look at the crank and pickup for contact.
 

MikeB

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Yes, definitely re-torque using oil on threads. And remove the cap again to inspect the journal and bearing inserts.

Is it a random knock, or rhythmic? Typically a worn out main bearing will cause a rumble, whereas a bad rod bearing will cause a rhythmic knock that varies with RPM.
 

AustinDube

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Well I havent started the pickup yet i just turned it over a bit and stopped, and yes this certain point it knocks after every rotation
 

74 Shortbed

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More than likely a rod bolt is contacting something..
 

CSFJ

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Flywheel bolts retorqued properly?
 

AustinDube

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yep 60 ft lbs with loctite on the flywheel
 

87ChevyR10

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Thread title: "Rear main seal done, Knocking noise"

I think someone forgot to let the gerbil out when they sealed the rear.

:sorry: :headbang:
 

vkh

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Thread title: "Rear main seal done, Knocking noise"

I think someone forgot to let the gerbil out when they sealed the rear.

:sorry: :headbang:

Oh my... Sounds like someone might be watching to much South park...
 

AustinDube

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I retorqued everything to spec with oiled bolts. The knocking went away.
 

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