96 Explorer, 4.0L OHV Leaking Coolant from under the intake a the rear of the engine.

[BillRod]

Hi All

Here's one for ya.

96 Explorer 4L Pushrod Leaking coolant from what appears to be under the intake at the back of the engine.

I have tried searching but cannot find pic's of that area of the engine to see what is in that area that might be related to coolant.

Any thoughts?

Thanks
Bill

 

[RonD]

Drivers side rear of intake is the coolant pass thru to the drivers side head.

There are coolant passages at all 4 corners of the lower intake/heads, but the flow thru the intake is from passenger side front head to drivers side rear head.

Both places are common leak points on the 4.0l OHV

Because intake is aluminum and heads are iron the gasket can be eaten away by electrolysis that happens if coolant isn't changed every 2 years.

Lower intake will need to be removed and new gasket installed, not very hard, just wrench work.

Other less common issue would be one of the heater hoses has a pin hole leak that is spraying coolant on the back side of intake, this would only happen after engine was warmed up and cooling system had some pressure built up inside.

 

[BillRod]

That was it. the rear of the lower intake was pretty much nonexistent on that side.
Also found the left head gasket was weeping coolant for apparently a while so I pulled that head too.

Debating leaving the right head intact since it appears to be solid.

Any thoughts if I should disturb thr right one since I'm already there?

Thanks
Bill

 

[cdxhizors]

Probably a few days too late but you've torn the motor to this point so I would do the head gasket swap on the right head also and would have both heads checked for cracks as they are prone to do so.

 

[BillRod]

Yeah that was my thought too, since I'm that far in I should pull both heads to replace the head gaskets.

Unfortunately the heads were shot, and the Cam is questionable, which explains a lot about how it ran after it warmed up.
It would take at least $300 minimum to rework the heads before magnifluxing them. So with $300 for the heads plus $150 for the gasket set head bolt set before looking at the Cam and lifters this was looking pretty expensive.

Calling around for heads one yard said no heads but he can get an engine for $600, throttle body to oil pan with exhaust manifolds, 115,000 miles & good compression.

So that's where I am at now.
I hope to have time to pull the block out this weekend and set the new motor before Daytona, we'll see how that goes.

I have some questions on the install but I think I will start another thread on that topic.

Bill