Engine temp a bit high

[Billder]

I have been lurking around enjoying all the information. I have a recently purchased 2002 Envoy XL SLT, 4.2 L, 128,000 miles. It was running a bit warm, 220 to 240 on the gauge, at highway speed, fine other wise. Changed thermostat and hoses, no change. Checked fan clutch, seemed to be working. Decided to let wife drive it on a 2 week, 2000 mile trip. The temp was not much of an issue, did better on the flat land to the north. Used oil, lots of oil. Other than needing about 3 GALLONS of oil to get home, it did great.
Mechanic determined we had big time ring blow by. Installed a 100K mile used engine, runs great, no SES light.
So, it still runs a bit hot, stays at 210 running around town, will go to 220 to 235 (first big hash past 210) at highway speed, A/C off does not change much.
- I discovered and did the burping procedure today, no change.
- have the new 198 deg thermostat on new engine.
- new water pump at engine change.
- i ordered a BAFX Bluetooth code reader and got Dash command for the phone, will get it next week.

While doing the burping thing I watch the coolant moving around, seems a bit milky and some very small flecks in it. I will do a radiator flush next. Should I switch from the green mix with anything premix which is in it now, to pink Dex cool? Any other cool ideas?

 

[Mounce]

The green antifreeze could be your problem. These things are designed to run on dexcool. Flush it real good before you switch to the correct fluid as the two might not like each other and dislodge a bunch of trash into your fresh fluid.

 

[Billder]

Drained radiator, the fluid was kind of chalky looking green. Not so bad that I was believing I was on to something other than good maintenance. Flushed radiator twice, nothing of note.
Retested clutch, might be bad. Disconnected and put a light bulb test lead off the power wire, watched the light flash (thanks for the video on that ?). Reconnected and was still able to stop fan pretty easy, no change when plugged in. I will head off the research the test on this well worn subject and , hopefully, flunk this part with some accurate knowledge.

 

[Billder]

Test drive, no change, went up about 3 "ticks" above the happy 210 mark. Tested fan clutch with towel (per Mooseman video), no tugging at all, it just coasted up when I let go. This is among the first things I tested, a couple weeks ago. Given the unknown history of this car I would bet this is a nice Dorman product and it crapped out,....or I faked myself out. Next stop fan clutch and fresh fluid instead of distilled water. Then on the the 14 other little things on the list.
Oh yeah, I removed 2 aftermarket electric fans stuck on the front of the radiator we discover at the engine change. Looked like a crap install and tell a story just being there.

 

[Mooseman]

Even with a dead fan clutch, it shouldn't get that hot unless you're in the desert or something. I had a dead clutch and it would just go a little past the dead center mark (100C/212f). Still recommend that you swap it. I would recommend that you get one for a 2008 as they went to a regular thermo fan clutch. You'll get a CEL for the unplugged fan but you can get a tune to get rid of it. It's cheaper than the failure prone electro-viscous type and with the saved money, get a tune.

I would also swap the thermostat again just to be sure, preferably with an ACDelco as well as the temp sensor just above it. It is possibly you got a new dud tstat. And make sure you fill and burp the system with a funnel like in this.
http://gmtnation.com/forums/topic/14083-bad-thermostat/?hl=funnel#entry455297

Two electric fans? I wonder if it was having overheating issues before and that was his solution? Instead of actually fixing the problem, just stuck those on. Who knows if that's what killed the engine in the first place?

 

[Billder]

I guess it was overheating before, fans did not fix, it showed up first time on a longish highway run. Have not noticed where the power was picked up or controlled.
Doing the math on the 08 conversion.
Outside temp was 80F on test.
Wont do anything till I get the code reader to see the real sensed temp.

 

[Mooseman]

So the only thing common between then and now is the radiator because everything else was changed. I'd investigate this. I'd also check that the condenser is clear and letting air pass through.

 

[Mounce]

Is the current fan the same one that was in it before the engine swap or did the new engine come with the fan that's on it?

 

[triz]

I would not rule out the water pump even if it was new. Especially if it was not OEM. Had one go bad in less than 30 days. Its been through 3 aftermarket water pumps as of today.

I did not have Dexcool on hand and just used the Amsoil coolant boost with distilled water. Seems to be running cooler at the gauge.

 

[Billder]

Been out of town a few days.
Fan and clutch and radiator are the same. Since I am sure the fan clutch flunked the "in overheat" operational test and it was common to both engines, I will replace it. Plan on using a non controlled unit. Have not seen any reason to stick with the original style other than to avoid having the PCM programmed. In for $130 plus the reprogram in the near future (when it runs at 210 deg). Should be done in a few days.
If this is no fix, I will consider the new water pump, but the clutch seems to be the unit not with the program.
Engine is full of green fluid and it kept coming out while I was flushing out every thing, think I will stick with it. Many report no problem and I use it in my other cars, no prob.
Other than this small detail the wife and I like the truck very much, a nice rust free southern machine.

 

[gmcman]

Used oil, lots of oil. Other than needing about 3 GALLONS of oil to get home

So, it still runs a bit hot, stays at 210 running around town, will go to 220 to 235 (first big hash past 210) at highway speed, A/C off does not change much.

3 gallons of oil?!?!?!

You need a cooling system pressure test/leak down test.

Also, 210 is normal, just slightly above 210 is normal when real got outside. If it goes past the 2nd hash mark after 210 then you can worry. When I'm pulling a trailer loaded with 3000 lbs of dirt, ac on, 50 mph. ...1 tick past 210 is where it will climb to.

 

[Billder]

Solved. Noob working on car with no scanner, got the BAFX Bluetooth and determined the indicator was showing too high. Actual temp was 97, centigrade I guess, on the "raw data" gauge. ( I'm a little twitchy about this truck right now). Using the free version of Torque, not sure which one to buy.
Did replace the clutch with the low tech version, not too bad of a job. No regrets on that, old one was not working. These fake gauges make me a bit crazy.
On to the rest of the list, lets see 9 items to choose from.....

GM: building good mechanics for over a hundred years.

 

[Mooseman]

Except for the fake oil pressure gauge, the others should be fairly accurate. Maybe your temp needle got moved or the stepper motor is whacked. On my 02 TB, it's pretty accurate.