Cooling sytem problem 7.3

Clb

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There are some tricks to purging the air...
Search coolant flush.anythibg over 2 hes run time after coolant cg,and topping off 3+ times' thats probably not your issue.
 

js5020

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stupid question, is the radiator cap new?

Questions are never stupid, questions create dialog/ideas that can bring a resolution. Yes the cap is new, along with the water pump, thermostat, and rad hoses. The radiator was also sent out and checked. We have essentially pressurized the system by firing up the truck and letting it run and build pressure with what ever is up with the system, it hold that pressure for hour, and I do mean hours I've seen 8 hours with pressure in the system, couldn't check the exact psi but it would be under 13 psi as that's the cap psi.

I do have a diesel compression gauge and adapters for a 6.9 around here, haven't used it in 20 years but I could run a compression test. This new tool will allow us to pull a vacuum in the cooling system and check that, and with what I hear/see with trapped air in these the tool will be worth it in the long run.

I am just trying to rule out any other possibilities before having the boys expend a lot of time and effort with no solution.
 

IDIoit

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Questions are never stupid, questions create dialog/ideas that can bring a resolution. Yes the cap is new, along with the water pump, thermostat, and rad hoses. The radiator was also sent out and checked. We have essentially pressurized the system by firing up the truck and letting it run and build pressure with what ever is up with the system, it hold that pressure for hour, and I do mean hours I've seen 8 hours with pressure in the system, couldn't check the exact psi but it would be under 13 psi as that's the cap psi.

I do have a diesel compression gauge and adapters for a 6.9 around here, haven't used it in 20 years but I could run a compression test. This new tool will allow us to pull a vacuum in the cooling system and check that, and with what I hear/see with trapped air in these the tool will be worth it in the long run.

I am just trying to rule out any other possibilities before having the boys expend a lot of time and effort with no solution.

normally, watching my boys expend time and effort, with no solution is pretty amusing to me LOL.
you know how teenagers are. you tell them to do it one way, then when their way fails, they do it my way anyway :D
 

Clb

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Yes riot your right.
Just throwing out some stickie worthy info.
Info based tech forums rock.
Its not a bubble, hope its just a gasket....
Seems they make a coolant test for fuel byproducts aka headgasket leaks????
 

js5020

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LOL Oh boy I have had enough entertainment, although hilarious at times it usually involves very creative solution by me. The last faux pas started out as checking the front brakes on my Grand Cherokee,,,,, I have never seen anyone make a lug nut perfectly round??? not sure how they accomplished it but they did. Ended up having to drill the stud to remove without damaging the rim and then replace the stud and lug nut.
 

79jasper

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Okay the vacuum tool helps for filling, and works great. Along with those special cooling system funnels.
And okay, you can pressurize the cooling system to check for leaks. Which usually works well.

Okay.... what about a vacuum test on the system?
I think if it's only letting air into the system, and not coolant into the cylinders/crankcase, Wouldn't the vacuum filler introduce more air?

Random thought while on the Ole pooper. Let me know what yall think.

Sent from my SAMSUNG-SM-G935A using Tapatalk
 

js5020

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Okay the vacuum tool helps for filling, and works great. Along with those special cooling system funnels.
And okay, you can pressurize the cooling system to check for leaks. Which usually works well.

Okay.... what about a vacuum test on the system?
I think if it's only letting air into the system, and not coolant into the cylinders/crankcase, Wouldn't the vacuum filler introduce more air?

Random thought while on the Ole pooper. Let me know what yall think.

Sent from my SAMSUNG-SM-G935A using Tapatalk

As I understand this device will create a vacuum in the entire cooling system as long as it is not compromised someplace and it can be tested for leaks, once certain there are no leaks coolant can then be put into the system and there will be no bleeding necessary. This should eliminate any chance of air in the system and confirm there is not a vacuum leak introducing air into the system.
 

snicklas

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Is there an anti-collapse spring in that new lower hose? We've had more than one that didn't and the water pump sucked the hose shut.........
 

laserjock

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Yes riot your right.
Just throwing out some stickie worthy info.
Info based tech forums rock.
Its not a bubble, hope its just a gasket....
Seems they make a coolant test for fuel byproducts aka headgasket leaks????

This. There are test strips for combustion products in coolant I think. If it's a gasket it might stay pressurized for a long time. Think of the head gasket acting like a check valve. A lot more pressure on the cylinder side. Pressurizing the coolant side may or may not show it unless it's getting pretty bad.
 

js5020

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Is there an anti-collapse spring in that new lower hose? We've had more than one that didn't and the water pump sucked the hose shut.........

Now that's an idea that many might not think of and the new hose didn't come with one, however the old spring was in good shape and I had them put it in the new hose.
 

js5020

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This. There are test strips for combustion products in coolant I think. If it's a gasket it might stay pressurized for a long time. Think of the head gasket acting like a check valve. A lot more pressure on the cylinder side. Pressurizing the coolant side may or may not show it unless it's getting pretty bad.

This vacuum tester/filler will be the last test, if the air in system problem persists either the engine will come out or the heads will come off as I don't think any more testing would be necessary. As said if we had overheating/running hot, oil in water, water in oil, or fuel in water it would already be out.
 

js5020

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Just an update, the vacuum filling tool arrived today and I had the boy drain the cooling system. Read the tools instructions and hooked up the tool and applied the 90psi. Pulled a vacuum but I noticed it started to struggle above 20, recommended is 24-26. Got it up to 25 and that was all it was going to pull. Pulled the shut off to hold vacuum and start the 20 second hold test,,, yep as most of us knew what the outcome was going to be, slowly lost the vacuum after 20 seconds we were at 20 and falling. Ok check all the hose connections and disconnect and plug the heater hoses, run the test again, same results.

Time to either pull the heads or the entire engine, which is preferred method?
 

MTKirk

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I pulled the engine, you could do it in the truck but I'm sure it would end up taking as much time, and be much more aggravating. Plus you can easily attend to other things like the oil cooler, oil pan, front & rear seals, etc.
 
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