Is this normal 22R Temperature Range? (1 Viewer)

[saywhat]

Hi All,

I have a 1987 Pickup 4x4 with a 22R (California Emissions). Recently replaced the thermostat (non dual stage), all coolant hoses, radiator + cap, temp sender and water pump. Noticed that the temperature will spike a touch higher than the middle of the gauge ("highest") for a minute or two, then go back to the middle. Sometimes, it'll go down even further a little higher than 1/4, "lowest". But it never has gone past the highest point, yet at least... . Before all the parts were replaced, the temp gauge always sat at the lowest mark IIRC after warming up.

It occurs most when driving on the freeway here in San Diego. Ambient temperature has been around 70 degrees +/-. This morning, it went to the highest point while in a drive-thru but dipped back down to middle, then to the lowest reading. Short drives around town, the gauge will be at or between the lowest point and mid point. I did "burp" the cooling system after replacing all the parts previously listed by parking the truck on a hill and running it with the cap off for a good amount of time. I'm inclined to burp it again but with the cap on and a hose as shown here



The temp readings are the same whether or not the heater control valve is set to cold or hot, which leads me to believe a dual stage thermostat will not fix this.

Also, I only get nice hot air when the RPMs are high. At idle, the heat air is luke warm at best. Which then leads me to believe I need to do more burping. Any ideas/suggestions? Dual stage stat? External temp gauge? Thanks for reading!

Highest Reading

Middle Reading

Lowest Reading

Pic of truck for posterity

 

[aztoyman]

Are you sure it's not coolant on top of the piston? Why would there be oil only on number 2? It's definitely not steam cleaned though. What's your next step? You can't keep us hanging.

 

[saywhat]

Are you sure it's not coolant on top of the piston? Why would there be oil only on number 2? It's definitely not steam cleaned though. What's your next step? You can't keep us hanging.

#2 is the only cylinder I squirted oil into for a wet compression test. I opted not to a wet test against the others since the compression seemed reasonable. Now that I have the boroscope, I may put everything back together, run the engine, and take another look with the boroscope. I'm not convinced it's the head gasket, but that's disappointing at the same time since I haven't solved it yet.

Got the new OEM radiator mounted and alternator installed. Waiting on coolant pipe from the dealer so I can button it back up.

 

[88repo]

#2 looks wet, but that might be from the oil I squirted in during the wet compression test. What do you guys think?

I'm thinking oil from your test but would ultimately have to do a taste test....
Looks a lot like mine did after my wet test, except my coolant leak was the TC gasket, not at the head.

Plus, I'd tend to think with that much coolant, if it was coolant, that the piston top would be much cleaner than it is.


Got that lower pipe in yet?

 

[saywhat]

Trying to squeeze wrenching time in between work and an out of state move in two weeks.

Got the pipe in, spliced in a new alternator pigtail and cleaned up the wiring. Tested standard OEM Thermostat versus OEM Dual Stage Thermostat, both have been installed on this truck.

Hard to tell from pictures, but to me, the standard thermostat appears that it would allow more volume flow versus the dual stage when fully open. Either way both thermostats pass inspection per FSM.

Going to install the thermostat (standard), fill up coolant, and burp after I take care of a few work calls this afternoon.

Dual Stage @ 212F

Standard @ 212F

 

[saywhat]

Filled up coolant, let the motor run for 30+ min in my driveway, burped a ton of air out. Tried my hardest to get the temp over 190F but no dice. This motor really doesn't put out that much heat sitting still.

Took her up the test hill but could not get the temp any higher than what's in the photo. 3rd gear, AC on and off, HVAC on cool and high, no difference in temp overall. Ambient temp is around 70F today. My earlier test was on a 90F day. Monday will be warmer so perhaps I'll try to do a longer drive to Temecula up I-15.

I did put in new spark plugs for the hell of it since I took em out. And the hoses from Mr. T are much nicer than the Continental junk I had in there previously.

 

[pappy]

That dash gauge look OK to me. Here is a page from my owner's manual.

 

[aztoyman]

Well that's good news. Hopefully good to go. I'm sure you'll be watching it like a hawk though.

 

[saywhat]

That dash gauge look OK to me. Here is a page from my owner's manual.

Thanks @pappy. The more internet reading I've done on 22R/E motors, it seems like a good majority of them have quite a "sensitive" dash gauge which I need to get used to. I've been more in the camp of: If it moves higher than where it normally sits, there is something wrong.

Well that's good news. Hopefully good to go. I'm sure you'll be watching it like a hawk though.

For sure. I won't stop obsessing over this until I get to drive it over a desert pass later in May. Fingers crossed..

 

[saywhat]

Just did an extended drive up a few good sized hills on I-15 between San Diego and Temecula. Approx 80F +/- ambient temp. Temp needle never even hit the middle of the gauge. Very happy so far. Green lighting our plans to drive from San Diego through AZ and NM next month!

 

[aztoyman]

Good to hear. I'm glad you didn't have to do a head gasket repair. Thanks for the update. Enjoy your trip.

 

[anndel]

Great to hear that. Hopefully it just had to burp.

 

[ntsqd]

Oooh, I know that hill! Good test spot. Glad it's working like it should.

Going to make it to the NM64 bridge over the Rio Grande? It is on our short list of things to see in NM.
NM64 Rio Grande Bridge

 

[saywhat]

Going to make it to the NM64 bridge over the Rio Grande? It is on our short list of things to see in NM.
NM64 Rio Grande Bridge

Looks awesome, we'll have to check it out!

 

[mike1305]

To ease your mind, and hopefully not make you regret all your troubleshooting, most of the vehicles I've owned did this. I always figured that the temp gauge rises as the t-stat is closed, then "peaks" a bit above middle right after it opens but hasn't began flowing in earnest, then dips back after a few minutes. My 1982 22R does this like clockwork. I think many newer vehicles either damp the needle more or have more of a "dummy gauge" to prevent owners like us from stressing out over what might be considered normal fluctuations in temperature. Cheers

 

[saywhat]

To ease your mind, and hopefully not make you regret all your troubleshooting, most of the vehicles I've owned did this. I always figured that the temp gauge rises as the t-stat is closed, then "peaks" a bit above middle right after it opens but hasn't began flowing in earnest, then dips back after a few minutes. My 1982 22R does this like clockwork. I think many newer vehicles either damp the needle more or have more of a "dummy gauge" to prevent owners like us from stressing out over what might be considered normal fluctuations in temperature. Cheers

Great to know I'm not the only one!

We drove from San Diego to OKC, no issues whatsoever. Didn't do any fun wheeling but it was a great trip.

 

[PAToyota]

Mine has always done the same thing and I have always assumed similar to Mike on the "why" of what's happening.

My guess is the change for you is that the spring in your old thermostat was weak and allowed it to stay open - or somewhat open. You'd never get the buildup and peak because the thermostat was never fully closed and would slowly warm up everything.