HALLO YOTA TECH

new here, with a
1984 22r sr5 4x4 Factory Lifted

Been running hot. Not reaaaally hot, but hot. Freeway speeds (a modest 55 of course) for 40 min or so and it starts to creep up. Slow grades same, steep grades definitely, going over the Grapevine on the 5 north (CA people know) always requires a stop. Easing back will cause temp to fall back, but once the creep starts on a hot day it's pretty tough to stop it if you want to keep driving, even if I end up doing 40-45 in the slow lane while people angrily zoom around me.

Speaking with people about what can be done to help out (already have a new 3 row radiator, though maybe I should have opted for a 4 row, already have removed the thermostat, flushed, etc), these people have brought up the idea of an auxiliary fan in front of the radiator.

My question is, would an aux fan help at all if freeway 55mph airflow already isn't doing the job? Plus will an aux fan help if we are in this blasted hell-furnace summer temperature? more airflow is more airflow, so it certainly couldn't hurt, and I would love it if this would solve the problem but I'm unsure.

Had several joyous long BAJA journeys in this truck in winter-time, but always been too nervous to try during the summer due to this. All advice welcome!

 

cooling been beat to death. But I'll say it anyway, you wouldn't have to upgrade the cooling system if you fixed whatever is actually wrong.

How's your pump, how's the fan clutch, is your fan and its shroud intact, thought about the transmissions role in this heat build up.

1: Yes an additional fan will move more air over the heat exchanger when it's running, if it's not on its just an unnecessary restriction.
2: Yes more air is always better, with the caveat. If the air is higher temp than your ~195 coolant, the heat exchange works against you. There is also some efficiency related to dwell time, where more and faster air doesn't have time to remove as much heat as it would at a slower speed.

Trust your Toyota engineering, they have lots of experience, fancy calculators to run fancier calculations off complex charts and tables and of course grey beards.
...
But really I just want to know more about the "factory lifted" vehicle like pictures and details.

 

water pump is brand new, thanks to a recently blown headgasket,

transmission is rebuilt thanks to my dumb sentimentality (the reverse lost some teeth up about 100 miles from the border, luckily managed to not back up for about a day)

fan, clutch, and shroud are in good repair,

might be wrong about the factory lift. i guess she's just got big tires. someone said that once, and not knowing anything about it i been repeating it. I'm not a truck guy, im a surfer, so this is my home away from home, and my chariot to some off-the-grid waves in Baja. but i'm learning slowly.

i'm the second owner, found her three years ago parked in an underground garage, undriven for about 7 years, 89,000 miles, with four flat tires and every rubber or plastic thing rotted to hell...first owner was a contractor who did the initial reverse gear damage, hence leaving it to die. got it for $600 which felt great, and got a year before the gasket and reverse gear let go.

but i'd really like to solve this, so all tips welcome. how would the transmission be involved? what else should i try? tell me anything you'd like pictures of and i can provide them.

also the AC was dead on arrival so i had thought of removing it's radiator, guess that might provide a good bit more airflow...

 

Look at your radiator near the bottom on the engine side, if you have the factory transmission cooler "loop", there maybe two lines that run back to the transmission.

The AC condenser is always going to have some effect, more so if the AC is active as well if the air passages are blocked.

The fan clutch can be functional but not optimal. RAD4Runner explained his issues, I think, in his build thread.

If you can compare the radiator inlet and outlet temperature (IR temp gun) it will give you a bench mark and sense of how well the radiator is performing and effects of anything you change.

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Do not forget the exhaust system and fuel mixture. These can cause excessive heat and keep it in the engine block.

 

Engine running hot hits close to home. Yes, I know Tejon and Cajon passes. Mine doesn't quite get to red zone, though. Still trying to figure it out. I have reasons to suspect that the the shop that I paid to redo my cooling system installed an old radiator. I may replace that when I have the budget.

SUWEET! My friend used to take his old Ford van and windsurf for days somewhere in Baja; about 2 hours from border, then another 2 hours on dirt road to beach. I'd like to visit the place someday.

Yes, auto transmission would add more load to cooling system.
Good and Bad fan clutch aka liquid coupling demonstrated here: https://www.yotatech.com/forums/f199...l#post52229129

IF after I replace the radiator it still happens, I might put a FUNCTIONAL engine compartment vent on fender like those on older trucks. That would make it easier for hot air that rises by nature to exit the engine compartment, instead of having to go down to undercarriage level. Maybe finish it with an intake vent grille from the G-Wagon that fits the size and geometry of the 4Runner fender. Heck, the new Wrangler has them and many newer cars have fake ones anyway. Mine would be functional and tasteful.

 

"cooling been beat to death. But I'll say it anyway, you wouldn't have to upgrade the cooling system if you fixed whatever is actually wrong."

"water pump is brand new, thanks to a recently blown headgasket"

These two taken together sparks the ol brain a bit. Head Gaskets don't just blow for no reason. My thought? It's an '84 with practically no maintenance history, so you don't know if it was maintained properly or not. I would suspect some "home mechanic" coolant changes over it's 35 years of life using tap water instead of distilled water. It probably overheated & blew the head gasket & is still running hotter than it should due to mineral scale & build-up in the block. That come s from using tap water in stead of distilled. You say you did flush it but you don't say if you actually used a flush chemical or for how long you ran it, or even if you flushed with clear water afterwards. Doing a coolant flush job properly takes time & flush chemicals usually do a very good job of dissolving mineral scale inside the block. However you did the flush it may have opened some things up, while others are still blocked or restricted, causing less coolant flow & therefore less cooling, which is why it's still running hot but hasn't blown out your new head gasket (yet).

Before you start spending more money, throwing 4 row radiators, aux fans & vents at it, try flushing it out again using a good flush chemical & following instructions to the letter. This is going to involve several "cooldown" cycles, which is why it takes time to do it right. 9 times out of 10 this will solve any "running somewhat hot" issues". Need video? Here ya go:

https://www.google.com/search?q=how+...GJggeDvLCIBg34

This vid is dead on the money on how to get ti done right. Only other things I can add is that The 20R & 22R also has a brass drain plug/bolt in the block below the exhaust manifold, that can be used to drain the block of coolant. I also after cooldowns during the flush process remove the lower radiator hose to allow any bigger "chunks" of scale, rust, etc. to get out of the system while draining. After 35 years there are bound to be some that the flush chemical loosens up but doesn't quite dissolve, & those won't drain out through the petcock valve.

 

Check ignition timing. Engines run with more, or less than optimal ignition timing reject more heat to the cooling system.

 

BLESS ALL YA'LL

these are all super helpful leads which I will chase down one by one. the flush chemical one also sparks something in me, gonna try that first and foremost. not surprised if its held lots of tap water in its day. my mechanic flushed it and i know he did several flushes, but im not sure if he used a flushing chemical...

fuel mixture is another, it's still got the original carb and that's been monkeyed with a lot to get it to pass smog recently. exhaust system sure might have some issues as well.


i will return with my results!

 

it's the life and the truth. baja is magical, the people, the food, the waves. i can guess where your friend was but i won't reveal his secret spot, haha. ours is about 3 days further...

been rescued on many a wrong turn by friendly locals with 4wd, which led to me finding this truck in the first place! foolishly tried to make the voyage in a HONDA FIT once, which actually performed heroically until it didn't! but a lot of those dirt roads are hard to gauge until you're several hours down them.

but once you get down them!

 

+ 1 on this. I did "heavy-duty" flush as mentioned on this Prestone bottle.
Did it with several empty and rinse cycles over a few days - good excuse for an ovenight road trip. However, I did not drain from lower ports - Will do that next time.

 

Alright so I went to the store early to get the Prestone, and then stopped by my mechanic to throw it in there because he's friendly and doesn't charge for that stuff, plus I'm in an apartment and don't have a good place to do this stuff. He almost had a fit and refused to help me, haha. He says if I use this stuff, likely I will melt the rust around my freeze plugs, and cost myself 800 bucks to change a $1.75 plug. And that likely I will spring a thousand leaks in a thousand other places. Since we did the gasket already, we know the cylinder heads are all clean, etc., he's skeptical that whatever's in the block would cause much of a problem. But he's also a very stubborn guy, haha. What he's saying makes some sense though. We agreed to maybe just try putting the thermostat back in (which we took out 3 years ago for a reason neither of us can remember), to give more time for the radiator to cool the water, to flush it a few more times with water, and to maybe remove the AC condenser to improve airflow. He still wants me to get the aux fan. He thinks timing and fuel mixture are all good since we just went through the smog dance, the exhaust could be something, but that's an expensive risk to take.

What do you guys think? Do I need to end my co-dependent relationship with this opinionated old man? Believe me I've thought of it before this. He has an existential dread and pessimism about all of this, and he's drawn to the band-aid of a fan b/c he doesn't seem to have the stalwart trust in Toyota engineering that I witness here. But I do value his wisdom, and desire to save me from expensive problems despite him being the one to benefit from said problems, haha.

However the heat has just finally broken here in LA, so now I have several months before this rears it's head again...

 

With the head off your mechanic likely got some sense of the condition of water passages; he's in a better position than we are to say if a chemical flush will help or hurt in your particular situation. If the old timer gets the work done on time and lets you know about what it will cost beforehand, I'd say he's a keeper unless you can find a Toyota specialist that does the same.

Definitely put the t-stat back in, but don't expect that to help much...if you don't remember why you took it out probably it was because you were having engine temp problems. If running the heater blows hot air and lowers engine temps when pulling up a grade, coolant system flow is probably not your problem, airflow probably is. If the heater helps I'd get the AC condenser out of there, my guess is that will make a big difference. The aux fan is a toss up. It could restrict air flow at freeway speeds. As others have said, if the fan clutch is at all suspect swap it out for a new OEM Aisin unit. Don't trust NAPA on that one.

Let us know if you get this resolved.

 

Oh yeah, the heater helps a good bit when going up a grade. That's good to know that that's a good flow sign. I'll take the condenser out first, and see how much that helps, then maybe explore a fan. Thanks this is super helpful.

 

I would personally be hesitant to keep your mechanic as he agreed to remove your thermostat (not a proper repair, just a cheap band-aid fix), and he insists that you add an auxiliary fan (also not a proper fix).

I would remove the grille and take a good look at the A/C condenser before removing it to see what condition it actually is in. Are any of the fins bent on the condenser? Any debris stuck to the outside of the condenser?

 

Does water pass through the AC condenser even when it's not in use?

 

No because it's full of refrigerant not water. =D

You just need to look at it, if you can see through all the air passages it's not your problem. Like mentioned above, check for bend fins (there is a tool iirc called a rake that will straighten these), look for bugs mud and debris (this can/should be washed out, gently or you bend fins).

Checking for exhaust blockage is super easy and cheap, and loud! Simply disconnect the bulk of the system from the engine, there is a joint on both sides of what is called the intermediate pipe. (Just after the exhaust manifold) With this disconnected (loose) you eliminate both crushed pipes and blockages in the catalytic and muffler.

You were presumably maybe suffering from temp control issues before the smog stuff, but it's definitely a common trick to lean out the AFR to pass one of these. A lean ignition runs really hot like melt your head or valve hot. There should be some excess fuel (rich) that's intended to quench some of this heat, when then gets consumed by the catalytic converter.

Conversely the TCCS EFI computer, which I realize you do not have, also has a warm up enrichment program. When the engine is cold it puts in extra fuel to speed the warm up. (The point here is both lean or rich can produce excessive heat)

Regarding the flush chemicals. If all that's holding the freeze plugs in are rust, sediment, and scale.. That's not safe to be driving around in its current state, especially since you venture off the beaten path. It takes a really long time to walk what you can drive in two hours.

Where you there when the head was replaced? Did the water jacket look good and not need any cleaning? If there was build up at the block-head interface that was "just chipped away" this material just falls into the passage then gets pushed into the (super tiny!!) Restriction ports in the head gasket and form blockages.

An IR noncontact temperature gun can really pay for its self in piece of mind alone. Compare the radiator inlet vs outlet (too much coolant flow, not enough air flow, or radiator and fan in prime shape).

Compare the exhaust runners from each cylinder (this can point out out of spec valves). An excessively loose tapet on the exhaust won't open the valve as far. Yes it might only one to a few thousandths of an inch but when you're dealing with that effecting the area if a circle (actually it's a volume of a cylinder) it can be a significant amount.

Compare each cylinder of the head, and six points around the cylinders (forward of center, center, rear of center), all of these should be very similar. If you can find two spots (one higher, one lower) that seem out of sorts with the rest it can be an indicator of one of those head gasket water ports being blocked. You can maybe free some of these up with the reverse flushing (water into the coolant outlet) which forces loose chunks out the way they came in.

If you bypass the heater core for the chemical flush there is no chance of that "getting eaten" and causing a leak.

 

JUST BY WAYS OF AN UPDATE:

Spent a week thoroughly flushing the coolant system (though not with a chemical flush, just water), filled it up with Toyota Red and distilled water, removed the AC condenser.

I was ready to declare victory as I made several long freeway drives and hill climbs that usually bring the needle up near the red, and watched it stay rock steady in the middle!

however I might have gotten cocky, and took her to Mammoth from LA this weekend and had a serious near-overheat on the final climb. To be fair, it was a hot day and that's a long slow grade followed by an 8 mile 6% grade. So it was asking a lot I guess. But stopped, let it cool, and she made it the rest of the way no problem.

So the report is, these two things (the flush and the improved airflow from removing the AC condenser) have helped a great deal. but obviously there is still some fundamental issue, either coolant flow or exhaust/airflow related. Gonna search for a Toyota Whisperer here in LA if anyone has a suggestion.

From this improvement, leaning more towards doing the chemical flush and embracing the consequences...