New Duramax owner loosing coolant

[duramax on fire]

My first duramax isn't going well. I have had to add coolant every time I drive it. Lost gallon in 400 miles. Truck has 191K miles 2003.

First off no coolant leaking on the ground or coming out the overflow vent tube.

When it cools the Upper hose has been collapsed some. System holds vacume even with new rad cap.

system will hold 14 psi with gauge for an hour. Cant find leak anywhere.

Then I noticed water droplets in the oil fill and then I pulled pcv hose and its almost clogged with a gooy substance. So some must be getting into the crankcase.

Now the oil deffently hasn't gained a gallon so I think most is being burned off. The upper hose never is rock hard, no bubbles in the overflow tank. Also checked for exhaust gases in the coolant. was none. also oil look good.

Ive spent days reading on this. But still cant make a decision. Can the injector cups [COLOR=blue !important][COLOR=blue !important]leak[/COLOR][/COLOR] coolant into the top of the head? where else can the coolant be going.

Love this site by the way.

 

[duramax on fire]

Pics of the pcv connection and what I pulled out of it

 

[02greysixer]

The injector cups can leak coolant into the crankcase. There are 2 o rings that seal the top of the cup keeping coolant and oil separate. When you pressurized was the engine hot or cold? It may only do it at operating temp or when stone cold. Either way sounds like you've done the basics and next step is to pull valve covers and inspect cups.

 

[duramax on fire]

Done it twice truck cold and like warm no change. I'm going to tear it down tomorrow morning. I'm just going to buy new cups and o rings since I'm in there. Can I reuse the o rings on the injectors. There 35k old. I figured on buying new copper gasket

 

[jdlover1]

new cups come with the two O-rings to seal them. I would replace the O-rings on the injectors just to be on the safe side.

 

[dirtydmax]

Is it a cali truck with an egr?

 

[duramax on fire]

No egr.

 

[duramax on fire]

well took valve covers off. Not sure what to do. The top of the heads were clean. But a lot on the covers. Couldn't see any evidence of the cups leaking. All glow plugs had some carbon built up so I don't think its burning it. I cleaned the valve covers off and put all back togather. The PCV system was stopped up completely. I have it dumping onto the ground know instead of the oil pan. Going to drive it for a couple more weeks and keep better track of the coolant lost.

Has anybody had good or bad experience with Blue Devil sealant .

 

[duramax on fire]

It washed of really easy with a water hose and the stuff didn't stain the valve cover at all.

Anybody else have this problem

 

[juddski88]

I strongly advise against using aftermarket cooling system sealants. It will gum up the radiator, thermostats, and cooling passages in the heads, not to mention that if it doesn't seal, you're further cross contaminating your oil. GM does have a tablet that they developed back in the days of the vortec motors that you can use safely, but it's not going to help you if its an unsealed cup. If it was mine, I would have the heads off and taken to a good machine shop to pressure test them.

 

[duramax on fire]

ok thanks judd. Im going to send off a sample of the old oil I just took out and go from there. I really didn't like the idea of coolant sealant. Rather fix it right. Are the factory head bolts ok for reusing or they like the 6.0 fords. Also which brand head gaskets are best to use

 

[juddski88]

You can't reuse the head bolts. And buy the headgaskets etc from Henry, cotnp.com

 

[Brent@LDS]

X2^^ the head bolts have to be replaced. I would recommend using the grade C GM head gaskets. We carry a complete kit. Let us know if we can help.

 

[duramax on fire]

If a cylinder is burning coolant wouldn't the glow plug be steamed cleaned or would it be solid black. I was reading another post on a guy burning coolant and his combustion chamber was solid black. I had one glow plug that was solid black. Rear driver.

 

[juddski88]

that's not the best indicator.

 

[duramax on fire]

that's not the best indicator.

Well just can't think of anything else besides pulling the cab and doing head gaskets and up. I thought maybe the one dark glow plug would tell me that's the cylinder and I could try replacing that cup. But was to unsure on a diesel if the coolant burning turns a cylinder dark

 

[DAVe3283]

I had a cracked head, and the glow plug on that cylinder was pretty dark. So you might have a cracked intake runner.

But to lose that much coolant, you should see the pressure leak down after a few minutes. Mine would lose pressure really quick. Start with a cold motor, and pump the coolant up to 15 or 20 PSI (20 won't hurt it), and watch it for 10 minutes. If it leaks down (and it sounds like it should), you should have enough coolant loss to figure out which cylinder it is.

 

[duramax on fire]

I think a lot of the first coolant loss was catching up on a low system.

I though it was odd one glow plug was extremely dark

Since the valve covers i have lost about a quart in 150 miles. Still getting steam and water droplets out of the pcv hose. Im probbaly going to try replacing the drivers side cups. Also I've pressure tested several times hot cold no loss. Can't get up over 14 my tester is leaking around the reservoir neck

 

[Brent@LDS]

I'm betting you have a cracked head. We just seen this issue with two trucks in the last month. Hope this helps.

 

[duramax on fire]

Well tore it down again. Pulled all cups. But I can't tell if there leaking. O rings are flat looking. Don't know if ya can see it in he photos.