Yeah, I should have said "Does it spin easily?" - it shouldn't.

When did you get that TJM on again?

 

mid february...

the more i read and the more advice i get, the more i think its the radiator. ill remove the fan shroud and spray down again, see if that does it.

 

btw, i really appreciate everyones help!

 

Keep in mind that in winter the radiator will have definite hot and cold spots even when fully warmed up as I found out (because the thermostat closes off as much as it needs to in order to keep engine temp at about just over 200 degrees and the water temp at just over 180 degrees). In summer the radiator should be nearly uniform from side to side but will probably have some temp gradient from top to bottom although the bottom shouldn't be much hotter than 190-200 degrees on your IR thermostat when fully warmed up.

BTW......an IR thermostat is a very cool toy to have (no pun intended)
If anyone doesn't have one, there are a few avail on Harbor Freight:
http://da.harborfreight.com/cpisearc...rd=thermometer

Here's what I was going to get:
http://www.harborfreight.com/cpi/cta...emnumber=91778


I agree though, that when I worked as a mechanic that I have seen the fan clutch blamed for overheating quite a few times where it turned out to be something else. If the fan clutch doesn't show any apparent leaks, roars at startup and spins with resistance after driving, then I'd say it was not likely the cause of the overheating.

 

Next time the motor temp goes over 1/2 on the gauge... pull off the road & lift the hood. Rev the motor & watch the fan (the clutch should be fully locked up). The faster the motor spins the faster the fan should go... If it is not spinning at the same rate as the motor... that's a problem.

 

isnt that impossible to do at the same time?

just kidding thanks ill try that. and jamie, thats good info. im gonna pick up an IR thermo tomorrow.

 

One more suggestion: carefully and repeatedly bleed the cooling system. Air sounds to be a real possibility from where I sit. I'd also suspect the fan clutch has gone south until it's proven to be functioning normally.

Couple of other thoughts, altho less likely IMHO: check the fan belt tension/condition and the cam drive belt tension. Very unlikely (but it's happened to me): retarded ignition timing can cause overheating in a vehicle with a marginal cooling system

FWIW, our '98 v6 Limited would never overheat, even in 90+ degree weather with A/C on while towing a 4,000# trailer up mountainsides. Your's shouldn't either.

Good luck. Please let us know when you've found it.

 

changed the radiator.. that seems to have solved it. i drove in a variety of situations with the AC blasting and that needle never moved a cm.

 

so what was the problem w/ ur old radiator? is it like what i described?

 

no, it mustve been an internal clog because it LOOKS good.

i mean, it really doesnt look like the fins are turned in a bad way or that there are clumps of mud or dirt in it... so it must be internal... something blocking the coolant from circulating properly, even though it did appear to be evenly hot. i never did get my hands on an IR thermo though.

anyway im just glad the problem is solved. i dont know if i reported this, but long story short i am set up at a parts wholesaler now as a business

so instead of the $579 toyota wanted for a radiator, i got one brand new for $179

 

i can get one for that price. too, but its from autozone....

 

[QUOTE=lee]no, it mustve been an internal clog because it LOOKS good./QUOTE]
What do you mean must've been?!? You did keep the old radiator so that you could open it up and see for yourself what was causing the blockage, right... right? No? Arrrggghhh!

Anyways, it would have been interesting to see pictures of what the inside of it looked like if that was actually the problem. Do you still have access to the old one?

Have you always used toyota red coolant or did you ever mix in any different kind?

 

yup i have the old one, didnt crack it open yet, thats all.

only ever used toyota red.

 

when i had both of the radiators out the old one was about ten pounds heavier than the new one so that was enough for me to know that it was clogged

 

This might be a dumb question but what would cause a clog bad enough to cause overheating in a 2001 vehicle? I've got a '99 and mine is doing fine.

Just curious.

Glad you got it figured out Lee, your Runner looks great!

Fink

 

no idea... i never thought it was the radiator, even while getting it changed.

oh well.. im just glad its fixed. sometime this month ill crack the old one open and hopefully solve that mystery.

my rig looks like poop right now actually w/ no rack (removed for better mpg's till i lift more) and the budbuilt skid pulled my truck down a bit

but july 9th im swapping lifts with someone and putting on their 305's, so itll look sweet soon!

 

btw, cleanin the radiator is another option. my neighbor did this and they pressurized it to clean the tube-track and test it on a flow-meter, and costs about 50bucks.

 

yeah i wanna get it refurbed and have it as a backup

when we head to paragon at the end of july, its really bad mud down there, so i wanna have it as a spare in case for when i get back.

 

Most of the time a simple recore will fix the issue (BTW most of the time when you buy a radiator from one of the big autoparts chain stores it is a radiator recore). The dealers in Canada just seem to sell recores too because only the aluminum section has issues 99% of the time and the plastic tanks on the top and bottom can be suffieicntly returned to "like new" condition for reuse. Hopefully you can at least ask for your old core back to see if you can see the issue (post pics if you see anything).

Also the Toyota red coolant uses phosphates which basically precipitate out of solution at times (which give the metals protection by doing so) so even when using the Toyota red it is important to flush the system about every 2-3 years (just an FYI, not saying that was your issue, Lee).

I also wanted to point out I saw a nice infrared laser thermometer at Pepboys for about $50 (in their flier this week it is #W89720).

 

I do think this was a refurbed radiator... but thats just fine by me, esp thanks to your info on what is done.

when i get the old one done, ill post pics.. i am sure i can get the original parts back.

as for coolant, i got it flushed at the beginning of each summer since ive had it (3 yrs now)... only ever used toyota red, so i assume that was not an issue, as you said.

thanks for the pep boys info.. i went to every place but there in search of one. ill pick one up next week after i finish buying the last of my lift components