454 intake manifold leadk

Hi. I have a 92 7.4 Merc Bravo 1. First. I did have the engine lifted by the hooks this winter to do manifolds and starter etc. Dropped her yesterday. It is spitting water and smoke or steam from the seam right between ports 3 and 5 on port side. Its a light spit. Increases with load. Obvioulsly my gasket is shot and probably has to do with the lifting. Fine. Can someone educate me exactly whats going on inside the intake at that spot. Is there a crossover exhaust port there? Should there be water coming from that area at all. Are there cooling passeges in there? If the gasket has failed internally also, where is the water going? Into the crank? Any description of whats going on in there or diagrams online would be great. I won't be able to do the gasket job for a bit and I just want to know. Thank you.

Re: 454 intake manifold leadk

There is a water port that goes through the front of the intake manifold and goes into the front of the cylinder heads. However water does not go into the manifold around where the intake ports are. The Intake manifold gasket could be the problem because they are probably low clamp load gaskets and when you lifted the engine you pulled up on the intake manifold. (I believe the front lift ring is hooked to the top of the intake manifold) So it could be leaking at the two water ports and traveling down the engine to where you say you see water and steam. However, It will usually suck the water into the intake port and into the cylinder because there is air being pulled into there on the intake stroke. Is there any steam coming out of your exhaust?

Re: 454 intake manifold leadk

Lifting rings are usually bolted to the heads passing thru the intake manifold.Should not be any force there to pop a gasket.If you had a front ring on the thermostst housing, thats a different matter.Water flow is thru the foward most part of the intake manifold and no passages between #3 and #5 port. There is water in the head itself ,so there could be a crack there.Is th eoil still clean? Worst case, drain the block and pull the intake to look.

Re: 454 intake manifold leadk

GM small and big blocks are notorious for intake leaks between cylinders 3 and 5, and cylinders 4 and 6, tho GM changed the angle of the bolts by these cylinders to increase the clamp load so as to prevent this. but lifting the motor by intake bolts can stretch the bolts, as a big block weighs a pound or two. it may not hurt to have the intake checked for warping or twisting before re-installing, just to be sure it's good. hate to see someone put it back on, only to find out the hard way that intake is twisted.

Re: 454 intake manifold leadk

Is there a crossover exhaust port there?
Should there be water coming from that area at all.
Are there cooling passeges in there?

I won't be able to do the gasket job for a bit and

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