Runs Hot - help please (1 Viewer)

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So which radiator did you replace with?
 
Can you narrow down the symptoms a little more. You say its OK at highway speeds but not when you are working the system. Can you confirm if the same issue happens with the aircon off as well as on.
 
* Does the radiator cap seal properly and open properly at 12psi?
* Check the input and output temps of the radiator
* At about 180-190 can you see the coolant start to flow? Stuck thermostat?
* Trans fluid level? Dirty?

Right now shooting clouds in the sky. As noted before, it could easily be more than one thing.
 
Can you narrow down the symptoms a little more. You say its OK at highway speeds but not when you are working the system. Can you confirm if the same issue happens with the aircon off as well as on.

Symptoms: Normal road conditions without A:C - no issues around town, in traffic, or highway. When off-road in deep sand (tires aired way down) and running moderately hard the engine temp begins to climb rather gradually above normal operating temp. and will get really hot if I don't stop and let it idle until it cools a bit. When towing small utility trailer (less than 1000 lbs) it will do same things. Climbed Mt. Washington auto road earlier this year, gradually got hot , had to put both front & rear heat on to stay cool. Hot summer days w/ A/C , runs fine until stuck in traffic - then A/C temp cutoff shuts down A/C. Couple mins. w/ A/C off and engine cools enough to use A/C again. There's never been a run-away over heat issue, it's gradual - like cooling system just barely can't keep up w/ heat production.
 
Just an FYI, the AC cuts out at 227* and turns back on at 215*

Do you have a ScangGuage? Are you getting no CELs?
 
Lets get some numbers.

And I think if your timing isn't on point, this can cause overheating issues also.
 
* Does the radiator cap seal properly and open properly at 12psi?
* Check the input and output temps of the radiator
* At about 180-190 can you see the coolant start to flow? Stuck thermostat?
* Trans fluid level? Dirty?

Right now shooting clouds in the sky. As noted before, it could easily be more than one thing.

NLXTACY- I know you chased this in your rig for a long time & you know how maddening this can be. New Rad. Cap from dealer - don't know about 12 psi open, how do I check that ? Coolant starts to flow at about 190 .
I'm on my 2nd brand new Toyota thermostat. Tranny fluid level correct- changed 2x in last 10k miles. Intuitively feels like trans. heat may be issue but not sure how to diagnose. Will try tomorrow to check temps in a zillion different locations. This is making me crazy
 
Hard numbers would help you. Consider a Koso if you are OBD I or Scangauge if you are OBD II. real numbers will really help. Hate to say it but you might need to try a OEM radiator. For me the CSF ran hot under load for me. OEM runs 188-194.
 
Did it run hot under load before you pulled the engine ?
Did the head gasket blow or did you do this work as a pm ?
How long have you owned it ? Does it start, idle and accelerate like it did before the engine was pulled ? Do you notice the change in fan speed as it starts running on the hot side with it idling and a/c on ?
Lean condition , vacum leak, will cause hot running condition, also as noted above ,ignition timming will too.
Have you connected a scan tool and checked temp. , o2 readings ?
 
Symptoms: Normal road conditions without A:C - no issues around town, in traffic, or highway. When off-road in deep sand (tires aired way down) and running moderately hard the engine temp begins to climb rather gradually above normal operating temp. and will get really hot if I don't stop and let it idle until it cools a bit. When towing small utility trailer (less than 1000 lbs) it will do same things. Climbed Mt. Washington auto road earlier this year, gradually got hot , had to put both front & rear heat on to stay cool. Hot summer days w/ A/C , runs fine until stuck in traffic - then A/C temp cutoff shuts down A/C. Couple mins. w/ A/C off and engine cools enough to use A/C again. There's never been a run-away over heat issue, it's gradual - like cooling system just barely can't keep up w/ heat production.

There are a lot of radiators up front on these wagons. You mentioned that you changed the cooling system Radiator but I don't recall anything about the transmission cooler. It could be that your tranny cooler isn't efficient enough (maybe fins are blocked) and thus isn't letting air through to the cooling system rad. Under load the transmission is working harder/getting hotter, keeping the A/C on just makes things worse.
 
Did it run hot under load before you pulled the engine ?
Did the head gasket blow or did you do this work as a pm ?
How long have you owned it ? Does it start, idle and accelerate like it did before the engine was pulled ? Do you notice the change in fan speed as it starts running on the hot side with it idling and a/c on ?
Lean condition , vacum leak, will cause hot running condition, also as noted above ,ignition timming will too.
Have you connected a scan tool and checked temp. , o2 readings ?

I have owned truck 4 yrs - PO (original owner) never had truck off road, didn't even know what locking diff was. Maintenance records showed dealer had repaired/replaced rear heater because of leak, suspect PO overheated it but he swears not. Always ran a little hot under heavy load (compared to my 93) since I bought My Wife overheated it once warming it up in driveway w/ truck buried in snow drift- popped HG. Starts, idles, runs better since HG, head and everything else was done. Yes, fan seems to "roar" when idling hot w/ & w/o A/C. No codes- Will be purchasing scan gauge this week to get accurate #'s . Will re-do timing- and go over everything again-no evidence of vacuum leaks.
 
When you had the head off did you notice any scoring on the cylinder walls?
When head was off, cylinder walls were pristine- factory cross-hatch looked like it was done yesterday. One of the piston tops was steam-cleaned, that was it.
 
Nope - Completely new exhaust system , no CEL, no codes


The cats can be plugged and it won't throw a code right away. I crushed mine mid summer and didn't notice anything but a lack of power at high RPMs. It wasn't until I was on my way back from Moab two weeks ago that it started to smell like sulfur.
 
Ultragauge is cheaper and gives you the same information, just sayin'
 
Does Ultragauge show the different monitors and if they are completed/ready ? I dont have one and cant find the info.
Thanks
 
I find it interesting that the first line of the OP's post has "wits end" in it and the thread is about running hot. Is this a guerrilla marketing thing?

I'm subscribing just to see how much cheaper he figures it out than Joey.

Sorry @NLXTACY. I couldn't resist.

Good luck to the OP. I have a 3FE. I can't go fast enough to overheat.
 

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