2006 H3, 111k miles. I have owned it about a week. The symptoms are:

- Coolant recovery tank is about 25% full. Red dexcool. That is how I got it, so it's not burning coolant noticeably fast in the 20 miles I have put on it.
- After cranking there is white smoke from the exhaust. Also keep in mind that outside temps have been in the 40s. After the car warms up, the "white smoke" us barely noticeable. Yet there is dripping from the exhaust (more so than just usual condensation) and I think it has s sweet smell.
- White milky residue on the oil fill cap inside. 1 day old fresh oil change. Dip stick looks fine though. So it's not making oil milk shakes.
- Engine bay does not drip a drop.
- Engine temperature gauge is a tick above the half-way line.

I found another thread on here where the person had the head gasket replaced, but he kept losing coolant. So I am looking for other areas to investigate. I know nothing about the 3500 vortec 5 cyl engine. I have built several engines, and plan to do this repair on my own. Before I got on this head gasket thing, I only pulled the front spark plug out of curiosity. It was new and look fine, so I did not look at the others and just put the air box back on it.

Question time:
1) Is there another area beside head gasket to look at?
2) Is the intake manifold a dry setup with no oil or water passages?
3) I have noticed a theme on this forum about an intake valve issue. Do you think this is related, or perhaps something to do while the head is off?
4) Do any of these motors hydro lock from coolant filling the cylinder and bending a connecting rod?
5) Do I STOP running the engine all together, or is it ok to put this problem off for a few hundred miles?
6) Is this H3 going to be a never ending project of fixing broke stuff?


Thanks for any help, or catch phrases to search for.

 

Do you have a car fax or other service history?

Condensation on the oil fill cap is not an indication of anything other than the vehicle has not been driven much and has not been getting up to full temp for long enough to heat out the moisture. Fill the coolant to the Cold mark and drive that thing and monitor the coolant level as you do.

I5s do not typically have any head gasket problems unless the prior owner overheated it and kept going.

The valve seat issue on 06s is for Vins lower than. From an old post of mine:

“The S/Ns affected is any 2006 H3 lower than 287591 .... the first one started with 100,001, your truck build date will be Nov. 06 or earlier. Not all have the problem, but some could. The head issue affected not only the I5, 4s and 6s were subject to the same issues. Call GM with your vin# and build date (from the sticker in the driver's door jam) and ask.

Just in case you're gonna say, wow they didn't even build that many 3s? The VINs are assigned at the same shreveport plant building Colorados and Canyons. Their VIN sequence unit #s are mixed in and subject to the same TSB re: the head/valve issue.

The recall and extended warranty was for very early 2006s, those with the 3.5L L52 Motors built before March 31, 2006. That is not to say some 3.7L LLRs have never had a valve or head issue. All the Atlas motors built since 4/1/06 have the new hardened valve seats.”

 

Might want to check the oil often to see if there is any coolant contamination over time.

 

That is good news and equips me to go learn more. Thank you. Will post back with VIN and for jam results....

 

Last 6 of VIN are: 148728, so lower than 287591. Monday I will call GM and find out if the recall/warranty was done or if it applies to this vehicle by starting with the Customer Relations Center at 1-800-462-8782.

I did notice that the hood was marked around the hinges for alignment as if the hood had been taken off. Which suggests serious engine work.

I will mark the coolant level and drive it a bit. If the coolant goes does, I will do a leak down test on each cylinder.

How does the dreaded intake valve seat issue present itself? What I mean is, does the weak intake seat cause a bad seal which results in poor compression or a back fire through intake and TB and a CEL? Or, does the seat fail into a water jacket resulting in coolant coming into that cylinder?

 

Sorry, no carfax yet. Anybody have the service and want to run it for me? VIN is 5GTDN136468148728

 

https://www.nhtsa.gov/recalls
if you run your vin there it states you have 0 un repaired recalls. so i guess it has been sorted out.

 

Thanks!
Epic VIN has a special going on for $1 for 3 days. I ran it there, but the results do not show maintenance history. And it only shows the total available recalls, but not if they got addressed or not.
From that though I did not see anything significant or worrisome. It had a $500 front left damage from accident in 2012. The person I got it from bought it in 2017 and he was the 3rd owner.

I got it for $6k. It was listed for $8500 a few months ago. It was a spur of the moment estate auction that I was crazy enough to bring my 15 year old son to who is vehicle shopping.

 

Progress. the 1-800-GMC number was a bust. However I called a local dealership and she said her records show the head was replaced in 2012 with 33k miles on it. I am going by there tomorrow to get them to print out that full report.
the marks around the hood hinges are still suspicious I doubt very much that a dealership would use black sharpie marker for reference marks on a yellow H3 that was 6 years old. So there's probably some shadey-tree mechanic action going on.

Oh, and the driver seat is now stuck fully back and will not go Foward. Going to get that fixed before putting more miles on it. Oh, and probably do the front diff' bushing as well. I'm not ready to call this thing a lemon yet. Struggle Bus maybe. (yellow jokes)

 

Funny story from the GMC dealership. The lady said on the phone she would print off the service records, but when I got there, she was reluctant to do so. My angle was that if I know it has the new head, then I will ask their dealership to do the Head Gasket replacement. She agreed and printed it. In comes the service manager to ask what I needed done. When I told him, he replied, "Is that the 5 cylinder?". I said, "yep". He said, "I wouldn't touch the motor with a 10 foot pole."
ha!

But I got my papers printed and some prices for the items that they can still get, like gasket and timing chain and such. Mostly to see if they still existed.

In the mean time, I have topped off the coolant, and I will monitor it over the coming weeks as time permits. Its a secondary vehicle until my son gets old enough to drive it. on to other item....