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Discussion Starter #1 (Edited)
well sorry to start another thread but i cant seem to pin point if it is hg or not after reading hundreds of other posts on this.

just bought my truck a few weeks back, truck is awesome and i plan on keeping it mainly stock for reliability reasons, besides the normal things people would put on to help lower egts and keep engine clean (exhaust, egr blocker, lbz mp, etc)

so after i drive it hard or normally the temps are anywhere from 185-210 or just under 210 trans temp at 130-160 everything running normal. i will open the hood every once and awhile to check coolant tank because im paranoid about the lly hg problems.

when i open the cap on the anti freeze tank after it has been run decently hard (right after truck shut off) the anti freeze will gurgle or bubble but never comes out of the tank, well today after i ran it for an hour in city and highway i parked facing downhill and opened the cap and it gurgled more then usual did not come out the top part of the res but it bubbled enough to spill 1-2oz of antifreeze out the overflow hose.

i've checked the upper hose at night after driving the truck and the hose was a little firm so i noted to check it in the morning before work and the hose was soft, no pressure in the tank when i took the cap off, and was no white smoke that i could see on startup.

i will buy a new cap this week, run some pressure tests on the coolant system, and go to cat and have them do a oil sample through my work to check for anything out of the ordinary.

or is this what seems small amount of pressure normal, as i know the system needs some to work properly.

- if it is headgaskets is it fine to buy oem head bolts and gasket kit from MA instead of using studs as i do not plan to tune it or do anything besides maybe and lift pump at most. as i dont want to spend $500 for 36 bolts :)

so what do all you guys think? :help
 

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if you have to do it do it right. ARP's and grade C's. that'll handle anything you throw at it in the future. down the road you will want to do more with it
 

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Discussion Starter #3 (Edited)
true, but i still need to make sure its hg or not... could it be a internal hole in the egr causing possibly more then normal pressure?
 

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Discussion Starter #4
i also have not lost any coolant besides that 1-2 oz today as stated above
 

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Discussion Starter #5
im thinking i should just do the heads and be done with it...

does $350-500 sound about right for heads being resurfaced, cleaned, pressure tested, and have a valve job done to them for the pair?

all said and done $1300-1500 for parts and labor on heads to do all the work myself?
 

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yeah sounds about right. lookin at about 5ish if you need new valves, and w/ studs. stud it or youre wasting your time, IMO. its only 600 for the set.
 

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Pressure when hot and recently run is normal, you only have an issue if your upper hose is hard after sitting overnite. Your being paranoid, your truck is fine, they all spew coolant if you take the cap off when they are hot.
 

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Pressure when hot and recently run is normal, you only have an issue if your upper hose is hard after sitting overnite. Your being paranoid, your truck is fine, they all spew coolant if you take the cap off when they are hot.
yeah and your lucky you didnt get sprayed.....and/or burnt.
 

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mine doesnt spew anything, it makes a small hiss but nothing dramatic. bleed the antifreeze sys. though the bleeder screw on top of the t-stat housing. then take it out and run the dog fuck out of it. If it starts leaking anitfreeze again probly gotta gasket going. my LLY hose is soft all the time even when running after doing heads and gaskets. EDIT: do not get a coolant sys. pressure test done its a waste of money. they said mine was fine two places and both sides #2 and #7 was blown.
 

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Discussion Starter #11
yea it did say on a service record that was done less then a month ago that the system was "drain water from system and add dexcool" along with rad and air cooler washed, blown out, and checked over again.

i think the t stats are working fine as the temp ranges from 180-210 when it gets near 210 the 2nd one opens and then drops to about 190 until it get back to 210 or just under. depending on driving and outside temp it has hovered around 195-200 range

so even tho the past 2 weeks of owning the truck the rad hose was soft while running, but the past 2 days it has been hard while running and hot. could the system have let an air pocket that was already in the system make its way to create a air lock almost and cause a hard hose while running?
 

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Any closed coolant system should build pressure while the engine is running-- usually around 15 lbs. You will have a firm coolant hoses-- the reservoir cap will bleed off anything over 15 lbs. That raises the boiling point to around 245 degrees- for better economy and lower emissions.

When you remove the coolant cap from a HOT engine, that reduces the coolant pressure to atmospheric pressure, and may cause the coolant. Be Careful!
 

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Discussion Starter #13
i guess i should have remembered that from basic science :rolleyes: its almost like dropping something into super heated water where a sudden change (like opening rad cap) causes it release its stored energy in a violent manner.

maybe i am just really paranoid :cookoo[1]: but i also want to make sure i dont ruin a still perfectly good engine.
 

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you wont hurt it that quick, im not one for good advice but I ran mine 60k miles blown and it hurt nothing, decked the heads, new valves, guides, seals, and springs, ARP's and its been wide open since.
 

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Discussion Starter #15
im just worried about cash right now as its coming to the end of road construction season and ill be laid off soon. since im going to school i cant file for unemployment. so breaking my truck which gets me to work, school, and where i need to go would be out of the question, thats why im worried/paranoid.

when it was all said and done for you, assuming you did all the work besides having the heads resurfaced and valve guides replaced etc. what did you end up paying in the end, 1k for gasket set and arp studs and how much for the head work?
 

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Stop worrying yourself.............................
 

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Put the money aside if you're that worried, drive it normal till you're back at work, and relax. MOST LLYs will not blow a headgasket. I bought my D-max cause of the power/reliability of my friends LLYs. If they were blowing them left and right, I'd have thought twice. One guy did blow one, but was running a PPE 120 tune and flat ROMPING on it. (Says he was gentle. But I've seen seen him:gearjamin)
 

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Discussion Starter #18
Yea true most people are running tunes who blow em.
 

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Most the time you can check the heads yourself with some simple tools and Gm specs I posted around. Aslong as you do not overheat it, the heads should be good. Not that bad of a repair, every gasket needed, down to even new exhaust manifolds gasket, up pipe gaskets, valve cover seals, that most do not give in their kit-- without a upcharge, and ARP studs --990.00 to the door. But it seems your over thinking this one. Drive it.
 

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Discussion Starter #20
that was one plan besides getting oil sent out to cat. i know the truck has been overheated once, and was taken to dealer right after to have it checked.
 
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