Hello! First time posting.. tried the search feature to find other threads similar to my problem but couldn't find any.

Anyways my 1990 4runner with a 22re is over heating trying to go up into the mountains. Down in town where I live its around 100F and it can idle for 30+ minutes fine and drives around town just fine. Even going out of the valley on the freeway around 40 -50 mph the temp gauge is just a little lower than halfway up the gauge.

Going to the mountains tho, at first its a low grade up (for about 5 miles) then it kicks up to switch backs. My car starts to go past the halfway mark when I'm going up the lower grade at around 35 mph, and getting to the first switchback it gets close to the red.

I realized today when I am going up to the mountains, I usually try to push 2nd gear with around 2.5k rpms, but I realized if I down shift to 1st and around 3.5k rpms I see the temp gauge going down. (I blast the heater aswell for it to work)

I don't have any frothy oil or coolant, no visible leaks and I have done the following..

New Rad hoses
New Temp guage (180f)
New Water Pump
New Fan clutch (6 months ago)
Coolant flush
Fresh Coolant
Installed a fan shroud

The only thing I didn't replace is the radiator.. but the fluid was clean when I flushed it, and I see the coolant flowing down the radiator so I don't think its that.. Also there is the bigger radiator from the 3.0 engine in there..

I am a little suspicious about the fan clutch tho.. I think the one I got was a dud, also I got it installed in mexico so I am not sure if I got the right one or whatnot from the language barrier. Also I didn't see any changes/improvements when it got installed.

Anyways I am about to buy a new radiator because its the last thing I can think of, but it doesn't sound right. One of my buddies think its the fan clutch but I am not completely sold on that..

Any thoughts? Thanks!

 

Did I miss thermostat on your list? Maybe it doesn't open fully when hot. You can pull it out and heat it in boiling water to ensure it fully opens.

I've never had an overheating issue with my 22RE with a lousy two-core radiator in +100F heat uphill in the mountains with a heavy load.

 

Can you hear the fan when it gets hot? If the fan clutch still free wheels or is easy to spin the fan when hot, it could be the problem.

How old is the radiator? I always changed my coolant and used distilled water and after a few years it was plugged up internally. I noticed that only a couple sections were hot. It was because many of the tubes were plugged. I had a shop rod out the radiator and all was well after.

 

Rule out the thermostat first. Then the fan clutch: "how to check a fan clutch" search utube. If they are ok, new radiator time. Got mine a couple years ago from Rockauto online. Spectra. Around a hundred bucks. Trying to "flush" a radiator at home is a fool's errand.

 

Sorry when I typed temp guage on my list I meant thermostat.
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When I first got the issue last week, the thermostat was the first thing I checked. The previous owner had cut the springs off so it was always open. Also when I installed the new one I can feel the top hose getting hot when the engine gets warm, so that seems to be working ok.

I YouTubed how to check a fan clutch on YouTube and it seems to be ok. I did the newspaper into the fan when the engine is warm to see if it stops, and it didn't, and when the engine is cold it doesn't free wheel too much. Maybe just one rotation or less.

Not sure how old the radiator is. When looking from the cap it looks fairly clean in there, no rust or anything, but I never used a temp gun on it to see if there is a clog. When I took the radiator out I also hosed it off on both sides to clear up gunk. But I do see a few of the cooling fins bent but not too many.

I'll look into a new radiator because thats the last thing I didn't replace. Would you folks recommend sticking with the 3.0 rad or get the correct 22re rad? I just got the fan shroud for the 3.0 rad so I would prefer that, but I'm not sure if that could be messing things up or not.

Thanks again!

 

Just ordered a replacement radiator for the 3.0 V6 4runner. I'll keep ya'll updated if it fixes the problem!

 

Since it's what you already had, I think you made the right choice for the new radiator. Why change? Especially since you have the shroud. My 88 has a 3 row brass 22RE radiator and it cools my 3.4 swap in Arizona heat just fine.

By the way, my radiator "looked" spotless inside and out. The radiator shop said more than 60% of the tubes were plugged before they rodded it out. It's hard to find a shop that will do it anymore and it's probably cheaper to buy new anyway.

 

I've checked a few local shops, for getting my old one rodded out. Every one of them quoted me a price higher than the cost of a 3 core, all metal radiator. In one case it was close, but still more. A couple shops wouldn't even give me a quote. Given the cost of the labor, materiel recovery fees, etc, they don't bother doing work like that any more. They just told me to go buy a new one, and be done with it.
Since I put an all metal, 3-core in my pickup about 250,000 miles, 30 years, ago, I figure it's getting close to time to replace it Still working, but not quite as well as when it was new.

Good luck!
Pat☺

 

Quick question.. can bad timing cause my engine to overheat in this situation? I've been looking in some other forums and I'm getting mixed answers. Some people say the pinging is a cause of overheating engines, and some people say it can cause the over heating.

When I am driving uphill (even when my car isn't overheating) I'm hearing something I assume is pinging (dice in a cup) when my car is under load.

I haven't checked the timing on my engine yet. Might stop by a shop to see how much they charge to do that, or see if a friend has a gun I can borrow.

Anyways radiator is coming in tomorrow and I'll see if that helps

 

"Bad timing" cause overheating. Short answer - Yes. You say that yours may have "pinging" evidenced by "dice in cup" sound under load. That sounds like preignition, spark knock, pinging, whatever it is called. Here's the general deal: If your ignition timing is "retarded" (occurs later in the compression cycle) that may cause higher engine temperatures. If the "fire" in your engine's combustion chambers occurs as a detonation or explosion rather than a smooth controlled burn (in milliseconds) you will hear it as the rattle sound. If you overdo detonation, it will severely damage your engine. If you're having mild detonation, then your overheating problem isn't like to be caused by retarded "late" timing. In any case, you should deal with the detonation. You need a qualified amateur or professional automotive techincian to check it out. My $0.02

Several reasons for detonation/pinging. Too much spark advance is one of them. And don't lug the engine. You can make an engine ping (at least the older ones) by "lugging" the engine.

 

Having someone else work on your truck is like having someone else work on your woman then paying them for it






MY FIRST-HAND CSF RADIATOR EXPERIENCE - totally happy once I found exact fit, if it would help:
https://www.yotatech.com/forums/f116...l#post52450555

 

Got the new radiator in and it seemed to fix the problem! Went up to the first switchback of the mountains (where I was overheating) and it stayed just below the halfway mark on my temp gauge.

My old radiator was def heavier than the new rad I put in, so I'm guessing there was a clog in there.

Thanks for all the info!

Still getting some spark knock when going up, so I'll search the forums to see what I can figure out about that.

Thanks again!

 

I tried filling my radiator with a 50/50 mix of vinegar and left it alone for 2 days. Then drained into a pan to see the results. Some dissolved minerals, but not much. But I also didn’t have any overheating issues, so maybe it was already fairly clean. Shocker the p.o. was pretty bad about any recent maintenance. So my test was inconclusive.

I’ve read about using muriatic acid or oxalic acid to clean out radiators. Since you’ve ordered a new one anyway, once you get it installed and the repair is done, it might be interesting to experiment on the old one. Muriatic acid is used in pools, while oxalic acid is referred to as wood bleach, so paint section. Both are very strong, so wear rubber gloves and eye protection. Good ventilation, too. I believe baking soda should neutralize the acid once your done with that.
Too bad rodding out is a dead art. Another casualty from the mass production of low budget parts.

 

Regarding "pinging"...here's an anecdote just for your consideration. I bought my '89 2wd 22RE 5 spd from my brother with aound 150,000 miles on it. He bought it new. Shortly after I got it, I needed to drive up to Fairfield to pick up a Chevelle hood and rt front fender. It was summer and usual temps 100+. I filled it with regular gas. It pinged bad. I had never driven a vehicle that pinged with a mild load on it.like that. I had to really "baby" the throttle. I topped it off on the way back with premium which helped a lot.. I asked bro about it and he said its always done that, and the shops couldn't figure it out. So I had to use premium gas in the summer. Not a big deal, since I only used the pickup when I was in Fresno once in a while. Years later, at 180,000 miles, number 3 injector failed. My mechanic said that they had good experience with rebuilt injectors, so that's what I did. Amazingly, with the new injectors the pinging went away. Runs fine on regular gas now. Winter or summer. I couldn't believe it, and I can't think of plausible explanation except maybe the factory injectors provided a lean mixture. Maybe a mixup of parts at the engine plant? Anyway, that's my experience for what it's worth.

 

I believe in regular, intense cleaning, BACKFLUSHING, and draining. Had been doing it every 2 years now. Pretty much any acid soaking should be good. If it eats through the metal, that means the radiator is on it's way out anyway.
Prestone flushing solution itself suggest "heavy-duty" flush, leaving solution in the system for a couple of days and driving several hours. Perfect excuse for an overnight road trip.

AFTER HEAVY-DUTY FLUSH ON 2007 COROLLA USING THE RED "EXTENDED LIFE" COOLANTI do not really trust shops and there is no accurate way to measure how well they did. I prefer to spend the money on brand-new well-built copper and brass radiator by CSF.

 

If you were a repair shop trying to diagnose an unusual running hot concern that was proving problematic, sending the radiator out to be rodded was a great way to remove it from the equation at a 1/4-1/3 of the cost of replacement. If you solved the issue, well, great. If not, than at least you didn’t have to wonder about it anymore and you didn’t throw a brand new radiator at the vehicle and still have a problem.
But yes, these days buying a new CSF would be more cost effective.

 

Detonation can cause serious harm to your motor. I'd make sure the timing is correct.