Tbi/vortec engine...

[GavinJansma]

Recently I put a set of vortec heads on a tbi block and when I put oil in it and started it, it ran fine. But when a put coolant in it mixed with the oil and half the coolent gushed out the back somewhere.. how can I fix this

 

[Nad_Yvalhosert]

Take it back apart and find where you messed up the gaskets. I suspect the intake is leaking into the lifter valley

 

[GavinJansma]

Take it back apart and find where you messed up the gaskets. I suspect the intake is leaking into the lifter valley

I bought the wrong imstake gaskets, so I used a tube of gasket Maker. That's the issue isn't it

 

[Nad_Yvalhosert]

I bought the wrong imstake gaskets, so I used a tube of gasket Maker. That's the issue isn't it

Likely.

By the way, what intake did you use?

 

[GavinJansma]

Likely.

By the way, what intake did you use?

I took the heads and intake off a 96 5.7 and put them on a 90 5.7 block I believe

 

[Nad_Yvalhosert]

Youre running the plastic Vortec intake on a TBI truck? How did a multiport EFI run without a crank sensor?

I ask because the TBI has a rear coolant crossover through the intake. The Vortec doesnt and neither do the intake gaskets. So that's likely where the leak is.
A TBI manifold for Vortec heads has to have provisions for that, and the rear exit coolant hose to the heater core, and the manifold mounted EGR...

 

[GavinJansma]

Youre running the plastic Vortec intake on a TBI truck? How did a multiport EFI run without a crank sensor?

I ask because the TBI has a rear coolant crossover through the intake. The Vortec doesnt and neither do the intake gaskets. So that's likely where the leak is.
A TBI manifold for Vortec heads has to have provisions for that, and the rear exit coolant hose to the heater core, and the manifold mounted EGR...

The truck is a 96 vortec that I blew 2 rod bearings in so I swapped the top end on a 90 5.7 good tbi bottom end from a junkyard.

 

[GavinJansma]

Youre running the plastic Vortec intake on a TBI truck? How did a multiport EFI run without a crank sensor?

I ask because the TBI has a rear coolant crossover through the intake. The Vortec doesnt and neither do the intake gaskets. So that's likely where the leak is.
A TBI manifold for Vortec heads has to have provisions for that, and the rear exit coolant hose to the heater core, and the manifold mounted EGR...

I also put a vortec timing cover on the block, I had to cut to small mounting tabes but otherwise the covers are the same

 

[Nad_Yvalhosert]

How did you put a crank sensor reluctor on the '90 crank?

 

[Nad_Yvalhosert]

It's good that you're filling in missing info that wasnt in the original post. But its like pulling teeth to get the details. Is there anything else you'd like to share?