New to me LLY

[shotgunwilly1117]

So I bought my first duramax two weeks ago. It had 194k miles and I've put a little over a 1000 on it. This morning I go crank it up and it says low coolant. I fill it up with water and run it with the cap off. I pull the bleeder and it's coming out about an inch to 1.5 inches.

Another thing I've noticed is after a 15 minute drive it has built up a good bit of pressure and after 2 hours it's still go pressure on it. I haven't driven it for a little while and then let it sit 6-8 hours to see if it still hold pressure. Also it hasn't over heated on me or anything.

Does this sound normal or should I be looking for a head gasket or some sort of coolant related issue? And when I get a chance what's the most prone place to look for a coolant leak? I don't have time til Friday so I figured I'd keep it full and look for it then since I don't have any long drives.

Also one of these weekends I'm gonna devote to maintenance such as ball joints, tie rods, pitman, idler, coolant flush, oil change, fuel head rebuild(leaks slightly), diff/transfer case service, and possibly the gm injector cleaner . Anything else I should look at doing?

 

[shotgunwilly1117]

If I know my head gaskets are good I'm gonna do a very small tune, intake, exhaust, and egr block. But I don't want to put that money into it all at one time if it needs head gaskets.

 

[OnTheFritz]

First clean your coolant cap with Dawn dish soap and some hot water. They can get a little gummed up. First thing in the morning grab the upper rad hose. If it is really firm... you more than likely need head gaskets. You can look for bubbles in the coolant tank also. If they are leaking you won't see it. It will go out the exhaust. Hope this helps.

 

[shotgunwilly1117]

Alright thanks. I've also heard it could help to flush out the red shit if I take the thermostat out and run it with water and dawn for a day or two. Is that true?

 

[chandler583]

EGR failure can also mimic a failing headgasket. Try deleting the EGR if you've got the funds and then see. You could also pressurize the coolant system to see if there are any external leaks.

 

[02greysixer]

EGR failure can also mimic a failing headgasket. Try deleting the EGR if you've got the funds and then see. You could also pressurize the coolant system to see if there are any external leaks.

A failed egr cooler almost always gives white smoke and/or coolant in the exhaust with pressure possible. And will bleed back off pretty quickly.

 

[shotgunwilly1117]

I reckon I'm just gonna check it in the morning but I've got a real slow coolant leak somewhere that I haven't found so it wouldn't hold pressure that long anyway. I'm thinking about doing the water pump since it's no doubt the original and I'll fix any other leak at the same time. Unless I can't find another then I'll hope that fixes it

 

[cstephens93]

You could be losing water from your weep hole

 

[shotgunwilly1117]

On the coolant jug?

 

[cstephens93]

Do a search for water pump weep hole