Cooling issue - not the norm trust me :)

[grizzlyls]

So, New Plastics, new hoses, new water pump december, new motorcrafst A/c last june ish. No water leaks on ground. Coolant level looks good in bottle. Bottle releases pressure when opened and its warm.

Car overheats with A/C on. It hit 95 the two days ago and it spot would overheat. Drove 35 miles mid day yesterday no issue. 2 miles for dinner last night over heat. I think its now doing it always with A/C. Heater full blast all works well. Leaving work had system off and it spiked to 220, so put the heat on full dropped right away. Heat- A/c System off after drive home idled 5 minutes at 210. Checked bleed point steady stream.

Gen 1

 

[pragmatic]

Does your hydraulic fan increase speed when the AC is turned on? If not your solenoid control valve is stuck. Replace it, or you can try running some sea-foam transmission cleaner (Hydra Trans Tune) in the fan hydraulic system to see if that allows the fan to run on high. Or you can convert to an electric fan.

 

[abes_linc]

generally caused by one of the 2, one is increased engine load caused by failing ac compressor as it adds rotational load to the engine so if the compressors going out its becoming increasingly harder to turn. or cooling system not working efficiently like plugged or blocked radiator fins, fans not working efficiently or a water pump. these are just my thoughts tho

 

[1LoudLS]

my money is on the standard 1st gen problem. hydraulic fan problem.

when it is overheating, is the cooling fan loud? like jet engine loud?

 

[grizzlyls]

yes the fan ramps up in stages with temp real jet engine loud if I let it slip up to 235+. If it cools down to <210 its fairly silent.

I am familiar with the solenoid, the mechanic didnt quite get the connector snug when he did the chains. Fan turned but didnt change speed. He cleaned the connector and reseated it and now it runs normal - no a/c is like its just blowing in wind, a/c it ramps up a tad. Coming off highway run and sitting at a light I could hear the fan with windows down while it cooled. Thats how it works now with heater on high.

 

[02LincLS]

My guess is there could be pieces of plastic restricting flow in the cooling passages or radiator. On my car, I have so many miles that the front (trans?) cooler has all the fins mashed over from getting rock blasted. It likely restricts flow to the 2 other coolers behind it. I've been monitoring engine temps for some time now and honestly, your temps don't seem too unreasonable. My idle is at 212, and I get spikes to 225, very rare spikes to just under 230. If you climb a hill in high gear, it jumps fast. If you're on the highway and downshift to 3rd to slow down, it cools very fast to about 206 or 208. This is true in winter and summer. Based on fan activity through this temp range, it doesn't seem engineers were too concerned with temps around 225 to even 230. If you're consistently hitting 235 or higher, even with A/C on climbing hills in high gear while its hot outside, then its probably time to fix something.

 

[joegr]

Well, it's a rare failure, but I'd try a new thermostat at this point (after verifying that airflow through the radiator isn't blocked by dirt or something else.

Other trouble shooting.
Measure the coolant temperature at the upper radiator hose and measure the coolant temperature at the lower radiator hose (at the same time).

Both high indicates an airflow problem on one sort or another.
Top high and bottom low and engine overheating indicates a coolant flow problem.
Top low and engine overheating indicates no coolant flow.

 

[grizzlyls]

Thanks for the hints Joe (and others) real helpful. This morn the fan didnt change speed at all! At this point I am suspecting that connector that worked loose the last time on that fan control solenoid. I got to thinking it behaves the exact same way, but this time it took a few days instead of couple trips to total fail.

Of course it could also be the solenoid took time to fail, either way I am going by the mechanics shop first thing tomorrow and having him check that connector again. Wish me luck!

BTW joe if you are watching this, any opinion on the sea foam thing pragmatic mentioned? At this point I believe my hydraulics are good and it has all new fluid in the system. There was never any chance of contamination or water in the lines like some with hard wear would experience in my case, so I believe all the components on this are probably as pristine as a gen 1 can be. Would it be wise to 'clean' it once (105k miles now) in order to keep it lasting as long as possible?

Post Note:
02lincls My occasional checks since december when all works well on my obd/phone temp gauge before this snafu showed usually sitting at 206 to 210 tops. Was real pleased with that. Should have looked at it when I did the 350 mile road trip at beginning of month, but didnt. Didnt really hear the fan working hard that day though, so probably was real good.

 

[twistedwrench]

I would say anyone having spikes over 210, even climbing a hill with A/C on has an issue. In the 2 years I've had my LS it's never once gone above 210. I've seen these hydraulic fans partially fail. My brothers LS was running hot at an idle 2 years ago, and temp would creep up under a load. We checked coolant circulation using an infrared thermometer to eliminate low circulation from a weak water pump, or sticking thermostat. We checked the fans and they ran like they were supposed to, or so we thought. After getting my LS we compared fan speeds...my cooling fan spun almost 2x as fast and was significantly louder(if your fan works like it should, you will be amazed at how loud it is on high). Anyway we removed the cooling fan, and there was a fair bit of resistance to the hydraulic motor. He didn't want to install an aftermarket electric fan, so he bought a new hydraulic fan, and it hasn't moved over 210 since. Point being, it seemed like everything was working like it should, even with his car overheating at an idle, had I not bought an LS it may have taken us forever to realize the fan wasn't working like it should. If your fan isn't SCREAMING at 235 you have a fan problem...honestly I'd almost bet on a hydraulic fan issue weather it's the solenoid or the fan motor itself.

 

[grizzlyls]

Update:

So Mech looked at it, didnt see any issues like me. Checked the actuator connection, looked hard for leaks etc. Been fine for 4 days now, dont know why it was acting up over the weekend.

Anyhow, if it happens again, going to have him pull that actuator either cause its on its way out, or the connection might be working loose. As a best guess.