isx cm871 coolant pressurized

[jlgc905]

I recently did the {**Content removed by protection bot**- content.}. Its a used truck that i bought. 2009 pete 387. Im having issues with loosing coolant. I ve noticed that with fan clutch onn at all times nothing happens. And with fan off amd NORMAL TEMPERATURE i IMMEDIATELY lose coolant. System is being pressurized. Water is leaking from overfill hose. Any ideas??

[gearhead]

Aircompressor or egr cooler, headgasket are most likely culprets.

[Waterloo]

2008 ProStar, same symptoms, 600hp ISX turned back to 485hp after figuring this out with @m*m^2. I did the EGR Cooler leak test and it passed. I checked the air compressor, not the issue, bought an exhaust gas coolant test kit at local NAPA store, she failed in a matter of seconds. It is the head gasket, tried to nurse her along after discovering it last year in what, August? I made it up until two weeks ago when the high pressure blew out the coolant line in my TriPac unit. I fixed that and filled up the coolant and now she is puking coolant a foot into the air. I did double check the compressor just to be sure, it is the head gasket. It has not gotten to the oil yet...

I need to do the bearings in the lower end too, and getting time for a clutch... Just installed a new radiator a month ago when it blew apart on me at a customer. To many new parts to mention and allot of downtime due to this problem. It is just knocking out system after system and is costing me allot of money.

She is going in for an in frame this morning... 900,000 miles, it's time...

[gonzo1949]

Waterloo what's the procedure to checking the air compressor?

[Rawze]

(03-24-2016 )gonzo1949 Wrote:  Waterloo what's the procedure to checking the air compressor?

Bleed the air to zero by opening the tanks for the truck, then place a blocking plate (a silver dollar works) over the intake pipe to the compressor and putting the joint back together.

Then check for pressure buildup in the coolant system.

[gonzo1949]

(03-24-2016 )Rawze Wrote:  

(03-24-2016 )gonzo1949 Wrote:  Waterloo what's the procedure to checking the air compressor?

Bleed the air to zero by opening the tanks for the truck, then place a blocking plate (a silver dollar works) over the intake pipe to the compressor and putting the joint back together.

Then check for pressure buildup in the coolant system.

So the pipe that comes down from the intake correct? How long can I run the truck like that to determine if there's any pressure build up?

[Waterloo]

(03-24-2016 )gonzo1949 Wrote:  

(03-24-2016 )Rawze Wrote:  

(03-24-2016 )gonzo1949 Wrote:  Waterloo what's the procedure to checking the air compressor?

Bleed the air to zero by opening the tanks for the truck, then place a blocking plate (a silver dollar works) over the intake pipe to the compressor and putting the joint back together.

Then check for pressure buildup in the coolant system.

So the pipe that comes down from the intake correct? How long can I run the truck like that to determine if there's any pressure build up?

I got my truck up to temp, then did the test. You aren't hurting anything, and it will not take long for pressure to build up if you have a head gasket leak. Mine took all of a few seconds to rule out the compressor, but I have a BIG head gasket leak, shooting coolant into the air... Have you done an exhaust gas coolant test yet? I am assuming you think you have a bad head gasket, correct? And if you have not done it yet, I would also do the EGR Cooler leak down test too. I did mine in the driveway with a radiator pressure test kit. It was an overnight affair, but worth it, my cooler was fine.

What is your truck doing that you suspect an issue?

[gonzo1949]

My buddy told me to bypass the coolant with a fitting and see if there's any pressure coming out of the top of the head

[gonzo1949]

Either a head gasket or compressor. Egr cooler is blocked off