My timing chain adventure begins..

[reamer]

I didn't either, until "Niagara Falls" started at the rear of the block

[ArdWrknTrk]

A coolant leak under pressure is quite a bit more serious than some dripping oil.

[reamer]

Now this IS puzzling.. The pin-hole in the rear right plug is what we know about.
The amount of coolant "splashing" was greater than a pinhole could produce, And the coolant was flowing out the rear of the block, But pulling the engine today, hoping to see a huge issue on the back,... I got nothing, clean and dry.... this is concerning....

[Gary Lewis]

Plug the water pump and heater hose outlets, and put about 10 psi of air to the thermostat housing.  That will show where the leak is.

But a Windsor has a coolant crossover between the heads on the front and, I think, the rear of the intake manifold.  If the one in the rear let go you could get coolant there.

[Steve83]

There's no crossover at the back, but there are coolant journals in the heads - they're just supposed to be blocked off by the intake manifold casting.  But if the intake gasket(s) blew out back there (which is common), coolant would pour down the bellhousing.

[ArdWrknTrk]

I'd be asking myself what I touched that c/would cause a massive overpressure.

A freeze plug rotting out or a gasket letting go, on after 33 years, okay...
But the freeze plug and a coolant gasket letting go -out of nowhere- after I spent the better part of a month screwing with an inoperable vehicle?

Sure, the radiator cap should let go at 13 psi. And the entire system should be equalized.

But if it was mine, I would be retracing my steps.
It seems very odd to me that this all happens at once

[reamer]

Very true, but as you mentioned, I just did the timing chain, and I'll stick the T-stat in some boiling water to see if it opens....

Once I get the leak-down tester, Ill set it to 10 PSI and check coolant system...

[Gary Lewis]

Thanks, Steve.  There was something in my mind that said it doesn't crossover back there, but I couldn't remember for sure.  But, as you point out, there's coolant in the heads there and if the gasket let's go there's gonna be coolant down the back of the engine.

Ron - Was this a new intake manifold or a used one when it went on?  I ask because the manifolds are frequently eroded around that gasket surface if people don't keep new coolant in the system.  That's due to the electrolysis that goes on with dissimilar metals in close proximity in the presence of a liquid.  So if that manifold had erosion at that spot it would be a weak point if the pressure in the system got up.

And, speaking of pressure, what is the radiator cap rated at?

[ArdWrknTrk]

With Windsor's you just have to be SURE that the head gaskets go "front"

Otherwise you WILL have a mysterious cooling problem.

[reamer]

Intake Gasket was installed 4-5 years ago when I trashed the feedback 2-v and went with the Eddy 4-v and intake. That appears to still be dry.

Just remembered I have a regulator on the handle of my HPLV Gun, So I replaced the one rotted plug, cleaned and installed a new plug (with RTV). I'll let that set up over night and inject 10 psi tomorrow...

[Gary Lewis]

You might have to seal off a few other "leaks".  But that will tell the tale.  

[Rembrant]

Curious to hear whats going on here. That must be the original '86 351 is it Ron? That 1pc rear main seal indicates after 1984 or so...

[reamer]

Original motor to the truck. Someone else has been in there... funky looking, wet oil pan gasket.

So I installed a new freeze plug on the one that ruptured, Did as Gary mentioned, Sealed off all water inputs/outputs, and injected 12psi into the water jacket. It sounded like inflating a balloon, then silence.

I disconnected the air hose and listened for any air leaks, Nice and quiet, no leaks in water jacket, no hisses from oil filler, PVC, or dipstick tube, no hissing around heads or intake, Ill have to take the engines word for it, that 1 pinhole HAD to be tossing all that coolant.

It took over 15 minutes to drop 2 psi, and I'm sticking to the theory of leaking out the hoses and radiator clamps to seal everything off. Then installed the rest on the plugs, Now I will retest....

I dipped the T-stat in boiling water, and it did not open...….even after 5 minutes and a re-dosing of boiling water.

I'll classify the water jacket as a "pass"

Next week I get the leak-down tester for the cylinders, If she passes, I'll install the new oil pan and valve cover gaskets, and paint it all in Ford grey.
I get to Save some huge cash VS a rebuild or a crate motor..
Since I love pain, (I guess) I also ripped out the NP 208 and handed it off to Terry's Transmissions, It is mechanically fine but it is the source of more fluid hitting the driveway than the engine is.

The ZF is dry, now the T-Case will be dry and hopefully the engine will be dry.... What ever will the wife complain about now?

[Gary Lewis]

Man, if it held air pressure that long you are golden.  But, are you going to replace the other core plugs while it is out?  Or, wait for the leak-down test and then replace them if it passes that?

My NP208 is cracked at the bottom and seeps ATF.  Could you tell where the leak was coming from?

All in all, several more layers off the onion.  

[reamer]

All plugs have been replaced, (not taking a chance)

Once it passes the leak-down, then its new gaskets, paint and "back to work"

T-case is leaking out the slip-yoke, where the 2 halves meet, and who know where else.
Terry will crack it open inspect and replace bearings forks chain, if needed, just needs a good "sealing up"

[Steve83]

reamer wrote

What ever will the wife complain about now?

I'll bet you the national debt that she finds something within a day of you saying the truck is finished.

[Rembrant]

reamer wrote

.... What ever will the wife complain about now?

lol. Well, there's always that potential '77 Bronco project, right?...

Mine was complaining yesterday because I went to look at an '81 CJ7 "project"...lol.

[reamer]

Ahh, yes, still looking for a '77, but even I agree, there's no need for a 15k price tag for something that "used to" be a Bronco, but closely resembles a rusted boat anchor….

[reamer]

Got the leak down tester today..
Looks like she's good for another 100,000 miles....
Set the gauge to 75 psi, and results are:

#1 75 in, 60 sustained = 20% loss
#2 75 in, 67 sustained = 11% loss
#3 75 in, 62 sustained = 18% loss
#4 75 in, 68 sustained = 10% loss
#5 75 in, 63 sustained = 16% loss
#6 75 in, 60 sustained = 20% loss
#7 75 in, 66 sustained = 12% loss
#8 75 in, 69 sustained = 10% loss

A little high on the loss side, but not an oil burner, and leaving 60' of rubber with the Cat cut out, I think its good for a few more years...
Thoughts?

[Gary Lewis]

So, 10 - 20% loss.  Sure beats Big Blue's 17 - 49% loss.  

I think you are good to go.  But, would do me a favor and try one cylinder at 100 psi?  That's what I use and I'm curious of that changes the %.