K&W Block seal

[chessman21]

should i remove thermostat before adding this permanent metallic K&w block/head seal stuff? Instruction dont say to but i dont know what the thermostats working condition is, it is new but after running almost hot plus now temp fluctuates from almost warm to almost hot back and and forth almost continuously now i dont whats going on under there.
I dont think system is building pressure either. Can the lower intake manifold gasket be the source of the leak vs the head/gaskets? If so can that be fixed without taking the heads off?

Be beter to find used engine?

Should i put a 302 in it... Whats the best years that fits?
Prolly doesn't work with the a4ld tranny id assume?

 

[RonD]

Do The Glove Test, free and easy, that will tell you if you have a cylinder leaking pressure into cooling system, i.e. blown head gasket or cracked head

Random temp fluctuations can be plugged up heater core, by pass core by rerouting heater hoses, to see if that's the problem.

Squeeze the upper rad hose before starting cold engine, should be soft and easy to squeeze.
After engine is warmed up fully squeeze it again, should be stiffer, harder to squeeze.
If it still feels soft and easy to squeeze then you have a leak in the cooling system.


There is no permanent fix for a leak except for repairing the leak.
"Stop leak" products are fine to use, no need to remove thermostat.

Most of these products react with air and some with high heat and air.
The head gasket fix causes glass(or metallic) particles in the stop leak to turn molten by high cylinder heat and air, and temporarily seal the leak.
For cooling system leaks the particles bind together because of air contact, much like your blood does to form a scab and stop the bleeding.

But temporary is the key word because the system heats up and cools down.
Metal expands when heated and then shrinks back to original size when cooled.
Gaskets are there to absorb that expansion and contraction, Stop leak seals become hard, they have to to work, so they will constantly fail and new stop leak particles will reseal the leak, which is why you need to leave the stop leak product circulating in the cooling system until you are ready to repair the leak.

If heater core tubes or radiator core tubes are partially clogged then the larger particles can close some off, which would have happened in any case over time, but stop leak won't clog up cooling systems that are fairly clean now, that is a myth.

 

[chessman21]

OK, going after rubber glove as suggested to start with, I know i make things harder than they are sometimes. .Again thxs for your help. If glove test shows no movement would that mean its the intake gasket? It was leaking bad the other day, not so much now. Drove 10 miles today & leaked allittle more than half a gallon. No skipping, engine sounds/feels smooth, oil looks good. Alittle white smoke this morning as it warmed up, normal i think.

On the bad side If the truck is runing and hot and you switch it off then back on it will sputter just alittle for about 5 seconds then clears up.. Could be a little water schoochin in to a combustion chamber.


Getting glove now thxs<

 

[RonD]

Whitish "smoke" on startup can be normal, depends on local weather and humidity
When you burn gasoline(H) with air(Oxygen) one of the by-products that comes out into the exhaust system is H2O(water)
This is why tail pipes often drip water and why exhaust systems rust from the inside out.

So when you shut off the engine some of that water vapor will condense inside the exhaust system as it cools down, that is what causes the rusting to start.
When you restart cold exhaust any pooled water will start to turn to vapor again, depending on outside temp you can sometimes see that as white "smoke"
Water vapor is ALWAYS there in the exhaust you can just see it better at lower outside temperatures.
i.e. if you watch the news from northern cities and see cars driving at slower speeds, or idling , in the winter they ALL have blown head gaskets, lol, all are blowing white "smoke" out the tail pipes

If there was a head gasket leak then it wouldn't usually go away after start up, with a small leak it can, but it would steadily get worse.

Yes, do the glove test to take head gasket leak off the table or to find out if that is the problem.

 

[chessman21]

Glove test

No movement from glove while turning cold engine over several times nor did it leak water. I can lightly thump the large hose and make the glove move so i know a good seal.

What does that mean? i need to pressure test it by forcing water through the fill hole somehow

 

[RonD]

Good news on the Glove test

With no visible external leaks, and you are for sure losing coolant then you are left with two things.
Overflow hose leak, will only leak after engine heats up.

Intake manifold leak, but not into oil pan, oil still looks good
Cold engine
Remove all spark plugs
Fill up rad, put cap on
Squeeze upper hose hard 10 times, that should squirt coolant out the leak point
Remove rad cap and check level, should drop a bit with a leak
Put cap on again
Repeat squeezing

If possible have someone crank the engine while you watch for coolant spraying out spark plug hole.
But you can usually see coolant residue around the hole after cranking

 

[chessman21]

Engine doesnt run like its got water mixing in combustion chamber but ill check. When i could see coolant coming out, it was coming from this area from timing chain cover.

 

[RonD]

That would be the common intake to head leak that occurs on 4.0l OHV engines.
Passenger side where lower intake meets the head.

Coolant flows from head to intake there and because of the different metals, cast iron and aluminum, that flowing liquid can cause aluminum and gasket to get eaten away.

You may need to pressurize cooling system to see it
Rent a pressure tester

 

[chessman21]

So,, replacement of intake & head gaskets..? So at the least that head will have to come off would you think? .. That k&w engine seal mess i got is staring to look good again,.,

 

[RonD]

No, just lower intake gasket.

But check that the leak is there

Upper rad hose is there as well, pin hole leak in that hose can spray on the front of the engine, misleading you as to where the leak might be