Does my 78 2F have a clutch fan?

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A comp test two years ago before the overheating problem developed really has no bearing. A test a couple of days before the problem developed means nothing. Check it. It is quick and simple.


Mark...
 
I hope I'm wrong, for your sake, but I've been there more than once.
Once exhaust gets into the coolant, it heats up really fast and you start seeing things like the rad cap releasing and blowing the top off the overflow tank. If you're going 55-60, there should be enough airflow to rule out the problem being the fan. It's unlikely to be the waterpump if it's not leaking or making noise so unless the thermostat is stuck closed, there aren't many other possible causes.

I know you did the compression test 1k miles ago but you weren't overheating 1k miles ago.
 
Make sure your system is properly filled with no air bubbles. I don't know what your upper radiator hose is like and if you are easily able to burp it using that. This is where flexible rubber uppers are handy instead of Reinforced acordian hoses.

Since you have already tested your thermostat, beyond this i would look for pinholes in the radiator, then head gasket last, especially if there is a loss of coolant with no visible leak anywhere.
 
Make sure your system is properly filled with no air bubbles. I don't know what your upper radiator hose is like and if you are easily able to burp it using that. This is where flexible rubber uppers are handy instead of Reinforced acordian hoses.

Since you have already tested your thermostat, beyond this i would look for pinholes in the radiator, then head gasket last, especially if there is a loss of coolant with no visible leak anywhere.

Those are reasonable things to check for minor overheating but he goes from cold to blowing off the overflow cap in 5-6 miles at 55 mph.
It ain't bubbles or pinholes.:D
 
^^^ Yep.

No point in chasing unlikely and obscure causes when they cannot be realistically expected to produce the severity of the symptoms anyway.

From what the OP reports... HG failure is the FIRST thing that should be considered.


BUT... I see that the first post states that the OP flushed the block and radiator... if you flushed it with off the shelf rad flush... all you did was wash loose crap out. if your rad is clogged up it will take an acid wash to clean it out.

If this has been an ongoing or slowly developing problem, then recheck the rad for flow and heat shedding performance.

If it is a sudden new situation... then back to HG.

Water pumps do not "work a little bit". The work or they fail. No in between.

F series thermostats almost never fail. I have seen exactly ONE in over 20 years of wrenching on these.


Mark...
 
It's really hard to fit a fanclutch in front of a 2F in a Pig. Toyota only did it in '78 when they put a 2-row radiator in the 55.
Pigs with 2Fs just do not run hot unless something is really wrong. If the waterpump is not leaking out the weephole, it's probably ok. Run your pig without the thermostat, see if that helps. I might pull the radiator and either give it a muriatic acid soak or have it rodded at the radiator shop. Check the big radiator hoses too, I have heard of them disintegrating on the inside and blocking flow.
But if you're blowing off the top of the overflow bottle, I'd do a compression test to rule out the head gasket...

Not trying to divert your thread, but I have a 2F from a 79 55 that I am installing into my 66 FJ45LV. Will the stock fan clutch setup work? How do I know if it will work? Is it a matter of if it fits it will work?
 
Very interesting, since I have exactly this happen to a car going highway speeds in 5-6 miles . Car shot to 240 degrees over course of a mile. I was in the middle of no where texas. burped system and added a gallon or so of water and was on the road.

There is an easy way to find out is the head gasket is blown or another leak for that matter. Just pressure test the coolant system. This will show your issue. You can also pull plugs a well and look for these signs.
 
My assumption was that it would be hard,as hell to under fill a cooling system on a Cruiser by a gallon."Burping" usually refers to getting the last few bubbles out of the system. In a four and a half gallon cooling system even being a gallon low should not cause overheating in 5-6 miles.
 
Not trying to divert your thread, but I have a 2F from a 79 55 that I am installing into my 66 FJ45LV. Will the stock fan clutch setup work? How do I know if it will work? Is it a matter of if it fits it will work?

Clutch fan fitment in a '40 (or '45) series is not an issue.

And yes, if it fits, it works (assuming the clutch is not bad of course).


Mark...
 
Shop says there is no trace of emmisions (carbon) in the coolant. Thusly they do not think it is a head gasket......Claims it is circulating.....did ask if it was the original radiator.....I am at a loss. Maybe I should buy a new radiator. Thoughts? I did go to the dealership in town and order an OEM thermostat because the one I have is Autozone or something. In all my spare time I will change out the therm with the OEM....thanks for the help and advice everyone....

Randy
 
Shop says there is no trace of emmisions (carbon) in the coolant. Thusly they do not think it is a head gasket......Claims it is circulating.....did ask if it was the original radiator.....I am at a loss. Maybe I should buy a new radiator. Thoughts? I did go to the dealership in town and order an OEM thermostat because the one I have is Autozone or something. In all my spare time I will change out the therm with the OEM....thanks for the help and advice everyone....

Randy

would an electric fan be cheaper and faster to test than replacing the radiator? or did you determine for certain that the fan is not the problem?
 
Fan seems to be kicking arse. No problems. I am thinking of pulling out the radiator and taking back to the radiator shop. I took it when I first bought the pig and they said it was okay....that was a couple of years ago. By reading other threads I may want to get it re-cored. I am thinking they just cleaned it up and flushed it checking for leaks when they said it was good. IIRC they only charged my 25 bucks!

I will beat this. It is now taking over my life!!! And giving me hot flashes. HAHA.

Randy
 
My 79 Pig did this when I first got it, Overheating at highway speed, assuming HG and timing etc are good is almost always a flow/radiator problem. I was going to just get a new radiator.......crap they are not available, so I mixed a 50/50 mix of Muratic acid water, layed the radiator down with the hose connectors up, filled and let it sit over night, it has performed flawlessly since.....3 yrs now in Texas heat.
And I have seen 2 water pumps fail due to the vanes being corroded away, unlikely in this situation....
 
Water pumps do not "work a little bit". The work or they fail. No in between.

my truck did at least 10 miles on the highway in what felt like a slightly dragging labored mode (at 65 no less ;p no change on the temp gauge) before the water pump finally exploded real good :hillbilly: and steam came out of the hood vents :eek:
 
Persoanlly I woukd do a compression test along with the Co test of the rad to make sure there are no indicatiobns of a blown HG.

If they only charged $25 bucks to flush your rad, I doubt that it got an acid wash. I would look at the rad for flow first based on what you have told us. Or just go ahead and acid wash it yourself.

If the fan is not a clutch fan, then there is no way for it not to work.

I have not seen water pump vanes corrode away but I have seen a couple of pumps in 3FEs seize up. Pump locked and belts slipping/smoking.

Usually the failure mode is bearing goes, pump start to leak and if ignorded the shaft pulls out eventually and the fan hits the radiator. Ugly.

Severely retarded timing can cause overheating too. As can a clogged exhaust system (crushed tailpipe).


Mark...
 
I would take the radiator to a radiator shop and have it rodded out and cleaned. You might ask them to not paint it after they are finished (excuse: because you like to paint it a certain sheen). By asking them not to paint it, you will notice if the top tank had been removed and resoldered. Removing the top or bottom tank is the only way to rod out the cores. For 25 bucks, the shop you took it to probably flushed it, air tested it and painted it. You should expect to pay about 75 bucks to have it rodded out and resoldered.
 
I am going to pull the radiator tonight and take it in tomorrow! Keeping my fingers crossed.....
 
Before I pulled the radiator I wanted to try the OEM themostat theory. Strike two.....still a boiling sound coming from the radiator and overflow bottle.....and running hot......though not as hot....but I didnt push it either. Dont want to mess something up bad.

After if cools I will pull the radiator....They told me today it would be between 60-100 bucks to rod it our or around 400-500 to re core it.....Ouch! Think I will go with the rodding out...they said the fins looked good.....

I do work at a swimming pool during the summers and there is quite a supply of muratic acid though....:D Maybe do the acid soak?

I'd prolly burn a hole in my garage floor though. What would you do with the acid/water after you let it set in the radiator for a day?

Randy
 
I would not let it sit that long...

Using fresh acid:

15-20 minutes soaking... drain and flush. Another 15-20 minutes.. drain and flush. You are done.

You can do it in the rig if you buy a couple of 1.5 inch "test plugs" for use with ABS plumbing pipe from the hardware store. Pull the upper and lower rad hoe and seal the openings. DO NOT put the acid in the engine. It will damage the AL of the water pump.

That is an absurd price to recore a rad. You can buy a replacement for under 200 last time I checked.


After you use the acid you can keep it around for derusting. I use it to remove rust stains in the bathroom fixtures at the shop since I have not added a water soften to stop them yet. I would not use a lot if you do though because it can not be good for the microbes in a septic system.

Poured over a bucket full of rusty bolts, it will strip them clean and bare in no time.

If you are on a city sewage system you can probably simply dump it down the drains with littler ethical concern. Most of it will bind with iron oxide in the system, clean things up a bit and render itself a lot less harmful than the rest of the mix.

If you are in town, or even near a county dump I am sure there is a toxic/caustic material disposal program.

Use it to clean your concrete driveway and dilute/rinse it away... this is done all the time in construction operations.


Mark...
 
Toothless not Topless.....

Thanks for the info Mark.

I think I am going to take it up to the radiator shop and have them rod it out. I am going to spend the weekend at the lake at my Dad's Vietnam Veteran Reunion with the family (I wish I could drive the pig).......

Should I ask the radiaotr shop to check to make sure it flows okay before they do that? What if they say, "This radiator works fine! It flows with no blockage at all."

That will suck. Is there something I can do to check the water pump (since everything is off) just to make sure it is operating at peak performance. I know everyone says it either works or does not work, but some have said they could tell theirs was going bad.....just wondering.

Anything else preventativie I could do why all this sheet is off here? Thanks to everyone for the input. I am addicted to this site....

Can you get new drop in replacement radiator for a 55? I thought they were real hard to come by....
toothless smile.webp
 
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