Weeping manifold Stud Gn'1

[KWIKR 1]

had this in the general tech section thought I'd move it here . replaced upper rad hose and did a pressure check on system . discovered the very front manifold stud on PS weeping coolant . very very little ...but it's still weeping . do the manifold studs/threads go into the coolant passages on GN1's ? thanks .

 

[charlief1]

Are you talking about where the intake and the head bolt together? If that's the case then you most likely have an intake gasket leaking.

 

[KWIKR 1]

it's weeping right from the intake manifold bolt itself . you can actually see it weeping out from under the washer .

 

[charlief1]

Intake gasket is leaking.

 

[KWIKR 1]

i've seen them leak in the corners where the manifold/block/heads meet . but never from out of the actual intake bolt .

 

[turboclam]

Tighten the bolt to see if it stops leaking. Iron or aluminum heads? Are you sure that the intake is not cracked where the bolt is?

 

[KWIKR 1]

nope ..intake does not look cracked . Alum GN1's . anyone know if the manifold bolt holes on the GN1's are "blind" ?

 

[turboclam]

Did you use the rubber rail gaskets or RTV (or both) when the intake manifold was installed?

 

[KWIKR 1]

It was done with RTV only by previous owner . how would the manifold seal to block/head have anything to do with coolant weeping from intake manifold bolt ?

 

[turboclam]

Well...if the intake bottoms out on the block rails then you won't get the clamping force with the intake bolts. (thus leaking) . You run into this with aftermarket heads/rebuilds/decking/shaving. This is one of the reasons why Champion sells intake spacers. If you're sure that the intake is clamped down properly you could try thread sealer on that particular bolt. What presure did you go up to on the tester?

 

[forcefed3.8's]

The intake bolts are dry. Sounds like an intake gasket leak going to the bolt hole as previously stated. If the intake wasn't sealing, there would be coolant in the oil and vacuum leaks. I would pull the intake and take a look. Putting sealant on the bolt is a bandaid. Either the gasket is leaking where sealant will do nothing, or the head is damaged.

 

[87GNSteve]

Put teflon thread sealant on the thread and that will fix that. You're supposed to put sealant on all corners; sometimes you get lucky sometimes you don't.

 

[Nick Micale]

I would put a couple GM pellets in the radiator and see if that works.

 

[KWIKR 1]

thanks guys ..looks like the manifold bolts have to be re-torqued...very lose on the one side for some reason , no where near where they should be . going to re-torque the manifold and re-pressure test . and also do what Nick suggested about throwing in a few GM pellets .