Help: LB7 Excessive Coolant Pressure

[gmasko]

First time using Tapatalk bare with me. I have had noticable orange discoloration around my water pump and heater core lines since ive owned the truck, 1.5 years never had to add coolant. I just replaced my injectors less than 1000 miles and have had erratic coolant leaks since. First my heater core quick connects leaked, replaced, stopped leaking. Few days later heater core to thermostat housing leaked, replaced o ring, stopped leaking. Few days later(today), coolant turbo feed burst a small hole, not fixed yet. Upper rad hose is hard as a rock, but no puking from reservoir hose. Injector cups stayed in and felt solid when I replaced injectors so I didn't touch them. I plan getting a new reservoir cap and "flywheel inspection plate gasket" already. Nonetheless I see a trend that's leading me towards head gaskets. Any other advise, what to look for, thermostats maybe????

 

[dirtydmax]

Id say try the t stats first.Could be stuck.

 

[gmasko]

Any way to tell for sure their bad when I pull them out? Getting tired of the cat and mouse game is all hahaha.

 

[Huffy67]

Sounds like slight head gasket failure to me. Not bad enough to blow out the overflow yet maybe. Only other thing I think it could be is if a cup was slightly leaking. You would know if one was leaking bad trust me!!!


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[Stancedlb7]

Sounds like slight head gasket failure to me. Not bad enough to blow out the overflow yet maybe. Only other thing I think it could be is if a cup was slightly leaking. You would know if one was leaking bad trust me!!!


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X2 on the injector cup. Tstats are cheap just replace em.

 

[07keo02]

Will the hose stay hard even over night?

 

[gmasko]

Replaced turbo coolant hose this morning. Need to wash out the ridiculous amount of coolant everywhere to check for leaks. Gonna look around for those t stats today, hopefully they are available. Will keep you guys posted. Yes upper hose is hard overnight, if I open the surge cap in the morning it releases pressure same as if the engine is hot.

 

[gmasko]

My main concern is that so far every leak fixed leads to another leak somewhere else. I am building too much pressure and it has to go somewhere. This time it went through my turbo coolant hose. Next maybe something worse. If these suggestions, which are great btw , don't fix it, what else could pressurize the coolant system?

 

[07keo02]

It's head gaskets or an injector cup. Sorry, T-stats are not going to keep the hose hard over Night. Considering you replaced injectors recently I can tell you it is highly likely it is a lifted cup. Did any cups come out with the injectors? If so, how did you reseal them?

 

[Huffy67]

Did it have coolant pressure before you did injectors?? That is the million dollar question!!


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[Minnesota DMAX]

I just went through the same thing my hose stayed hard overnight and then eventually started blowing out the overflow.I guess It wasnt so bad now I have studs and had the heads rebuild. But now I'm in the process of putting in a new cp3.old one blew apart on the way to work, diesel coated the bottom of my truck.Not a good way to start a Friday morning

 

[Huffy67]

I drove mine for like 3 yrs with a hard hose. My radiator looked like it was starting to leak a little so I tore it down and fixed it... No big deal lol I got a little carried away and spent almost $10k in the process.


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[gmasko]

07keo: I was told 2 things about cups before doing my injectors. If it doesn't come out, leave it alone. And if it doesn't come out then pull them and reseal. Being inexperienced, none came out so I left them alone.

 

[gmasko]

Huffy: Not like this. Before injectors my hoses would be soft after cool down and nothing leaked. Except of course a rare single drop from heater core connects and water pump weep hole, as mentioned. Thanks though. Big "duh" moment, I should lean towards cups since working on them. Lol.

 

[Huffy67]

If none came out they "should" be fine.


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[gmasko]

Won't have a new cap till tomorrow, so I will update. I know its a long shot but hey, wishful thinking. BTW thanks to all for quick replies and a bit of direction if that fails.

 

[Huffy67]

10-4 report back.


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[dirtydmax]

You could pull the t stat's and cover while doing them and watch for bubbles in the crossover pipe.That will tell you which side is leaking.Your already there might as well!Keep us updated and good luck

 

[07keo02]

While not impossible for it to be a coincidence and your head gaskets started leaking right after you did injectors, logic says it's a cup. Yes , people say to leave them alone if none come out. Sometimes you can create more harm then good fixing what isn't broke. Unfortunately, however, there have been plenty of cases where none came out but one was slightly unseated not noticed by the naked eye. I can't think of a case where just a bad cap will allow pressure to stay in the cooling system overnight. I know every recommends to try it (me too). It s 15 bucks and a lot better than the alternatives. Even with a bad cap, the hose shouldn't be hard in the morning. If your getting fairly "relative" overnight lows it would likely be the opposite and be collapsed. The continued, slow leaking of combustion through the cup/head gasket into the system is what allows that pressure to remain, even through the overnight lows.

 

[gmasko]

I feel like a jerk off for leaving you all hanging after your valuable input so for that I apologize. I have good news though. I bought the surge tank cap and thermostats as recommended. Only replaced the cap as my process of elimination. Drove my truck over 350+ miles this week from Sacramento to Bodega Bay for work. So far, all is well. No pressure in upper hose overnight, therefore no leaks. Temps rose up as I drove normally, topped out at 195 (Edge CTS), never heard the fan kick on. Runs cool if you ask me, but no reason to suspect open t stat just yet. Nonetheless you guys are probably right about cup/hg leak somewhere. Time will tell hahaha. Thanks again!!!!!!