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new 408 head gasket?

F1shifty

Well-Known Member
so, im trying to dial my new 408(351windsor). Had to pull the distributor today anndddddd milk. :( brand new motor. seriously has ran maybe 5 -7 minutes tops. oils overful, radiators low. I didnt put it together. im gonna go by the place and see what he has to say in the morning but im just feeling out if anyone has an opinion. Like i said it ran maybe 5-7 minutes. seperate times at that. I dont think it even had chance to get to temp to blow a gasket. So im wondering maybe if theres an internal galley plug? head bolts that pass through a water jacket? ANYTHING. Im pretty sure im gonna end up pulling the heads but just trying to grasp for any other cheaper/easier solution I can. theres no oil cooler so i know thats not the case. Sorry for the long post. Thanks for any input.
 

partybarge_pilot

Well-Known Member
Probalby wrong intake manifold gaskets or, 351W and 302 actually had different water ports and some combonations of heads and manifolds do not mix. Head gasket water holes are all the same 351 to 302. Only odd balls were the Cleavor motors.........
 

07FJRog

Well-Known Member
Probalby wrong intake manifold gaskets or, 351W and 302 actually had different water ports and some combonations of heads and manifolds do not mix. Head gasket water holes are all the same 351 to 302. Only odd balls were the Cleavor motors.........
Cleveland motor ( big block 351)

Improperly sealed INtake gasket is my guess also. But I would also check the heads and head gaskets now as well
 

Slippery P

Well-Known Member
How did the intake fit? Sometimes due to block and or cyl. Head surfacing the intake will not fit in the valley very well and with that comes poor sealing. I've had to machine the intake before to seal properly.
 

F1shifty

Well-Known Member
Intake was brand new and heads were gone through. Talked to the guy who built the motor and he suspects it detonated and lifted the gasket due to it not being tuned for that size motor. Looks like its coming back apart. Thanks for the replys
 

Slippery P

Well-Known Member
Sounds fishy to me.
 

07FJRog

Well-Known Member
Sounds fishy to me.
I agree, I highly doubt detonation lifted the intake gasket, sounds more like improper assembly/preparation to me.
 
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