M1009 Cooling System Overpressure

[GreggVA]

I think I have a blown head gasket but my carbon testing fluid is telling me otherwise. The top chamber is supposed to turn from blue to green but I tested it twice and same results. I am loosing coolant and seeing bubbles in the radiator. I am not "making oil" and the color is a nice brown and not milky. I am hesitant to pressure test the cooling system for fear of pushing coolant into the cylinder if it does have a blown gasket. There has been no noticeable change in power and runs clean without any white/dark smoke from the exhaust. I am new to diesels so struggling with how to do a compression test. I am guessing you would remove the injector and used that as a port? Would the compression be that much off to show if it seems to be running fine?

I found some other good threads also below that I have read through.



http://www.steelsoldiers.com/showthread.php?134949-Head-Gaskets&highlight=head gasket

http://www.steelsoldiers.com/showth...or-change-engine-survey&highlight=head+gasket

 

[Drock]

Well I would say the fastest & easiest way to check would be to remove all the glow plugs, and pressure check the radiator. If it does blow coolant into a cylinder you'll know right away, either by sound or coolant running out. Then if you want to still run it for a while, you can disconnect the pink wire on the injection pump and turn over the motor to blow out the coolant. Then reinstall the glow plugs.

 

[GreggVA]

Well I would say the fastest & easiest way to check would be to remove all the glow plugs, and pressure check the radiator. If it does blow coolant into a cylinder you'll know right away, either by sound or coolant running out. Then if you want to still run it for a while, you can disconnect the pink wire on the injection pump and turn over the motor to blow out the coolant. Then reinstall the glow plugs.

Thanks. I replaced the glow plugs not too long ago so they should come out fairly easily. I have never touched the injectors so was hoping to stay away from those.

 

[m38inmaine]

There is an adapter that replaces the glow plug to do a compression test.

 

[GreggVA]

There is an adapter that replaces the glow plug to do a compression test.

Thanks. Guessing the process is similar to a gas engine plus pulling the pink wire on the injection pump. I'm sure somewhere in the tech manuals it states what the proper pressure and variation between cylinders is but will take the answer if you know it!

 

[m38inmaine]

I seem to remember 400lbs is ideal, but I would have to refer to the manual. Yes pink wire and crank.

 

[Haoleb]

If that is a picture of your combustion tester then you are doing it wrong. I bought and used that same tester, you are only supposed to fill the blue fluid up to the line on the sight tube on both the top and bottom chamber and it should be a lot darker blue than that. Then you need to have about an inch or so of head space in the radiator so you can suck in the gasses and not coolant.

 

[Blood_of_Tyrants]

If your head gasket is leaking into the water jacket, you will be seeing bubble when you take the radiator cap off (when cold of course). Also the leaking ggas will cause the coolant to be forced out or the overflow into the reservoior.