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Head gasket leak/compression loss

B

Brooklyn Tow

9 11 Never Forget
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Brooklyn, NY USA
OK, New problem.....Seems the truck overheated about 2 weeks ago, while idling....She got pretty hot about 240-250*.

The issue seemed like the T Stats were stuck closed, the upper hose got as hard as a rock......I noticed this when the overflow tank was spitting out coolant.

Turned the truck right off, opened the rad cap to release the pressure.......started it back up, refilled the coolant (about 1 gallon).......flushed the system with clean water, but the bleeder screw is now spitting out air.

I bled the truck for a good hour and still air......How would I tell for certain that there is not compression getting into the coolant?

Oil is still black (no water), didn't change the T stats yet but air is still coming from the bleeder screw and on cold start the upper hose got hard today (never before)....T stats are on order.

When I drive local she's not overheating, nor do I see any big temp swings.

There are NO bubbles in the coolant tank like Kenny has......Can it just be the pressure from the bad T Stats forcing out air from the Bleeder?

Can it be from that back intake stud at the tranny dipstick, where the water Jacket is??

What to check????

Also that flush direction didn't seem correct......I emptied the rad from the drain plug, but when I went too add fresh water thru the top of the rad, she didn't go thru the system as explained.....The upper hose was dry and the water just overflowed from the neck, where I was filling it, not going into the block from the bottom hose as directed:WTF:

Any opinions or input?

http://www.thetruckstop.us/forum/sh...ound-Stud-bolt&p=346106&viewfull=1#post346106
 
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Also that flush direction didn't seem correct......I emptied the rad from the drain plug, but when I went too add fresh water thru the top of the rad, she didn't go thru the system as explained.....The upper hose was dry and the water just overflowed from the neck, where I was filling it, not going into the block from the bottom hose as directed

----------------------------------------------------------------------

My understanding.....

I think there are "switchbacks" as in horizontal passes that the water has to flow across the radiator tubes a few times.

The water pump is a positive pressure pump not positive displacement. It pressurizes the top of the radiator and lowers pressure at pump inlet the bottom of radiator so it induces flow. So if you are at the top of radiator and take off a hose or cap water surges up when the pump is trying to circulate water. Coolant will take path of least of resistance (surge out). As the pump lowers pressure at bottom hose it will pull water thru radiator core. When you take off top hose you loose half? the pressure differential to create flow through radiator/block.

It should circulate eventually but again you have less flow than when system is a sealed circuit path.
 
So what would be the most "efficient" way to flush (Get the water circulating through the system) and from which direction do you think I should introduce the water, also where should it exit?

It sounds like it should be an easy procedure, but in fact it is not.
 
Time to pull the crossover off the block. Fill the engine till the water is at the top of the crossover ports on the head. Take off the fan belt. Start the engine and look for bubbles. This (bubbles) will let you know if you have to pull a head and what side to pull. Overheating at idle is an airlock condition and suspect cracked head or blown gaskets.
 
Not sure I understand this correctly:

you still have the stuck closed themostat's in the truck and your driving/trying to bleed it?

If so, you need to either pull the unserviceable stat and run it without them at all or stop driving/running it altogether....
 
WarWagon said:
Time to pull the crossover off the block. Fill the engine till the water is at the top of the crossover ports on the head. Take off the fan belt. Start the engine and look for bubbles. This (bubbles) will let you know if you have to pull a head and what side to pull. Overheating at idle is an airlock condition and suspect cracked head or blown gaskets.
Click to expand...

Well it would be nice to know which side, I'd do them both and USE ARP studs. It's not that bad a job,,,I'm getting alot of practice at pulling 6.5 heads lately. Pull the pass side wheelwell. Makes life much easier for the 15 mins it takes. I hate to say it but it sounds like a HG or head. It probably will start bubbling at some point as it gets worse.
 
BTW Louis, the coolant in my 93 looked pretty murky. It happens from the compression leaking in. My oil was fine. In fact it seems 6.5 HG failures rarely seem to affect the engine oil like a gasser. I don't recall ever reading of anyone having peanut butter in the crankcase.
 
I have at least 3 engines that got coolant in the oil. It turns to sludge. The oil pump seems to be able to pump it to the main and rod bearings but not the cam.


IMG_2004_13.JPG IMG_2007_16.JPG
 
WarWagon said:
Time to pull the crossover off the block. Fill the engine till the water is at the top of the crossover ports on the head. Take off the fan belt. Start the engine and look for bubbles. This (bubbles) will let you know if you have to pull a head and what side to pull. Overheating at idle is an airlock condition and suspect cracked head or blown gaskets.
Click to expand...

Jeez, I was hoping that it was just a bad T Stat or two......This just happened once and as soon as I relieved the pressure she cooled right down. Thats why I thought Bad cap or stats,......Maybe it was just that, and now that it over heated the heads or Gasket are now pooched.

great white said:
Not sure I understand this correctly:

you still have the stuck closed themostat's in the truck and your driving/trying to bleed it?

If so, you need to either pull the unserviceable stat and run it without them at all or stop driving/running it altogether....
Click to expand...

Seems that whatever started this fiasco was a one time event.......Stats seem to be acting "normal" again, it's just after I refilled, I now can't get a non air filled stream of coolant from the bleeder screw, that I have seen/done so many times before.


Acesneights1 said:
Well it would be nice to know which side, I'd do them both and USE ARP studs. It's not that bad a job,,,I'm getting alot of practice at pulling 6.5 heads lately. Pull the pass side wheelwell. Makes life much easier for the 15 mins it takes. I hate to say it but it sounds like a HG or head. It probably will start bubbling at some point as it gets worse.
Click to expand...

Can't I come to your house?......LOL;):hihi::???:
 
This weekend would be no good as we have company/plans but possibly next if you are desperate. The only problem of course is if it turns out to be more than a HG I have another lawn ornament.....:D
 
This weekend would be no good as we have company/plans but possibly next if you are desperate. The only problem of course is if it turns out to be more than a HG I have another lawn ornament.....
Click to expand...


Desperate is my middle name........But between your luck and my Black Cloud, something like that seems about right.....
 
bk95td said:
I have at least 3 engines that got coolant in the oil. It turns to sludge. The oil pump seems to be able to pump it to the main and rod bearings but not the cam.


View attachment 27162 View attachment 27163
Click to expand...

I thought these engines were top-oilers, -meaning the mains/rods are fed from the cam journals??

One thing is for certain, that bearing is smeared into oblivion.....
 
Theory......when the most rear coolant block off plate stud was removed for that PCM ground wire and braided strap were connected, it gave me a little trouble and coolant was weeping out from there, and at one point I had the stud out.......could the block off plate gasket/silicone not be sealed correctly, causing it to mirror the cracked head(s) and/or HG symptoms of my air/compression in the coolant ?

Or am stretching here and the coolant block off plate, even with a bad seal(ing) surface would not cause the symptoms that I have, of a bad HG or cracked head(s).......Is this possible?
 
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