Yeah I'll look into getting those test strips. I don't know why I didn't think of that!

The truck has 280k, 20 on the rebuilt motor out of a truck with 350k, brand new rad, would, hoses, and coolant.

So. In all, probably 360k on the block, 20k on the rebuild. I'm pretty sure the heads were not touched when the motor was done, I don't remember seeing that line item on the invoice.

 

Ok guys I might have had a breakthrough.

The other day, I was about to refill the coolant again (it had puked out the cap again) and it wasn't as low as I knew it should be. I took the cap off and it relieved a little pressure but not as much as I was expecting. I pulled the top rad hose and voila the coolant level dropped two inches in the degas bottle. what the heck!!

SO what I gathered from that is: the top rad hose hole DOES NOT vent to atmosphere when the degas bottle cap is off.... The hose from the top of the rad-bottle is clear, and the bottle itself isn't blocked. What the heck! Is the top radiator tank not open inside???? Is there a block between the upper rad hole and the overflow hole???

fyi, This is a brand new Mishimoto radiator.

 

Mine does the same thing. The top hose never really feels like it's full of coolant to me either. But mine never overheats.

Burping these systems and getting all the air out of them is not near as important on these engines as on some other engine families (LS, anyone?). The cooling systems on these trucks are generally MORE than adequate to keep them cool, especially for everyday driving. Heck I ran mine for a full year once with the cooling fan removed.

If you're still overheating, I hate to say it, but I think you still have deeper issues. I don't think it's the cap, the bottle, the rad, or anything else. I think you have an issue in the mill. Pressure / compression tests are really the only way you're going to know for sure. I'd start with adapting a compression tester to accept shop air, pressurize each hole (through the GP hole) individually and then see which one leaks down or produces bubbles in the degas bottle. You'll want to get the piston to BDC for the test, but if all the GPs are out that should take care of itself when you add air pressure.

 

Thanks for the input, Nate... Just to make sure I explained my situation correctly, here's a picture:



I vented the port with the blue arrow to atmosphere, but the system still had pressure which was released when I pulled the hose off the port with the red arrow. I was under the impression that those two ports were connected in the top portion of the radiator.

 

I guess you could throw the stocker back in and see, bit I am with Nate on this one. Too many arrows pointing to mill...(coolant in cylinder, history, rebuild, etc....)

 

I'm not sure I understand why that would have been the case either. I sure would have thought those ports would have both been connected to the top tank.

 

I am going to put the thermo fix and stock rad back into the truck as a last ditch effort to avoid pulling my second head.

Hopefully if it is the brand new rad, I will get my money back...

 

I wouldn't pull the second head until you do some further investigation as I outlined above.

Pulling a head is a pretty expensive (in terms of time anyway) way to try and diagnose an issue and it doesn't eliminate the possibility of a pinhole somewhere in a bore due to cavitation or something else that may have been missed with the rebuild. Your best bet is to do some TESTING to identify the source of the issue so you can take the action that you know will resolve the issue.

No need to work overly hard on this, just use SCIENCE! Go all Martian on it and Science the 5h17 out of it!

 

Oh yeah, Nate.. Pulling that head is the last resort I'm totally with you on testing first.

But before the testing can happen, I need some warmer weather!! It's cold outside!

 

Ok guys... I have some money to spend on the truck upgrading some stuff. Best brake booster? I'm seeing AC Delco, Cardone, and Concentric on Rockauto... Any better than the others?

Also, would anyone else be in on a group order for redheads? I think Eric is interested... I could get two (one for the power stroke, one for big green) Anyone else interested?

 

 

I'll look into it. Thanks!

Any brand in particular that anyone has had success with? They all seem to have meh reviews....

 

 

I was kind of thinking about hydroboost to be honest.... I'll look up some threads lol

 

https://redheadsteeringgears.com/pro...olt-top-cover/

Yes, I am down.