2 fan clutch's later and it still doesn't engage- RESOLVED (1 Viewer)

[brooks202]

Howdy Mudders,
My 60 started overheating on a road trip to California (im in CO) this summer. I noticed the engine was real quiet- usually the original fan clutch would always be engaged unless it was below 10 outside (not normal but I liked the roar). I figured the 40 year old fan clutch fluid finally gave out and luckily there was an auto zone with a cheap "it fits" replacement that could at least get me home. No such luck. The new clutch didn't engage either. Every time I drove for more than 20mins the gauge would go to red and coolant would boil into the reservoir. IR gun would read over 200 degrees on the radiator and I remember the bottom of the radiator was a good 20-30 degrees colder than the top (water pump problem?). Ended up copying someone on MUD who tied a rope around the fan blade onto the pulley and it was enough to get me home. Now that I'm back in CO I got a proper AISIN red clutch and put it on yesterday. At first when I pulled out of the driveway and it got quiet I thought it was a dud, but after the engine warmed up around town it DID engage- until I got to the test road. Going up a steep mountain road holding 3kRPM in 3rd gear (maybe 45mph?) within minutes I was in the red and the clutch never engaged. Was able to coast back to town down the hill and cool her off. I'm just confused. The air blown by the non engaged fan seems decently hot and the top of the radiator is hot enough for coolant to boil, yet the fan clutch won't do anything about it. I have noticed for about a year that my coolant does tend to disappear and get dirty (probably oil) over time so that could be contributing to the overheating if my gaskets leaking but the clutch should still engage given the radiator is melting hot...

Any advice?

EDIT: I also changed the thermostat in California but they didn't have the upper O ring which should mean more cooling. I also flushed the radiator and through the trip probably replaced 4 gallons of Toyota red coolant from all the time it purged itself so it's all fresh. Radiator cap and hoses are new.

 

[fjc-man]

Maybe it’s not the fault of the fan clutch, maybe it’s insufficient air flow through radiator and A/C condenser because of dirt, debris, bugs. Get to a shop and ask to have a tech blow it out with compressed air from the fan side out.

 

[brooks202]

Maybe it’s not the fault of the fan clutch, maybe it’s insufficient air flow through radiator and A/C condenser because of dirt, debris, bugs. Get to a shop and ask to have a tech blow it out with compressed air from the fan side out.

Yeah I've sprayed water through there a few times but never had a professional clean it out. My buddy works at a shop a few blocks away I'll take it there to clean it out and see if that does anything. Appreciate the input.

 

[tmxmotorsports]

Go back to the thermostat and put the rubber o ring back in . Your thermostat is probably not opening because of it . Look it up Google search it should come up with threads about it on here

 

[brooks202]

Go back to the thermostat and put the rubber o ring back in . Your thermostat is probably not opening because of it . Look it up Google search it should come up with threads about it on here

I definitely will do that but in the short term do you think I should just take the thermostat out completely and see if that does anything? Interesting that the missing O ring could cause it to stay closed didn't think of that

 

[brooks202]

By the way this is what my coolant looks like after 3 months. I drained it to swap the fan clutch because my rad hose is in the way. Looks pretty bad
I was hoping that the dirt just comes in from my broken reservoir cap but that seems wishful

 

[CaptHamster]

I had terrible luck with the "stock" red AISIN fan clutches on my FJ62. They never seemed to engage when I needed them and when they did, it was kind of weak and they would kick off too easily. Check out my old thread about picking up a light blue fan clutch for an FJ80 (I think) and tuning it. The light blue clutches have an adjustable spring in front that lets you change what "temperature" they engage at, and you can even change out the fluid inside the make it lock up harder and stay on longer. I did both on mine, adjusted the timing of that engagement spring and added a much heavier silicone fluid inside and it works fantastic now. Pulls much more air than an electric fan ever would at full tilt. I had a couple issues with running hot that were probably related to poor maintenance on my end but the fan helped the most significantly. Since taking a thorough refresh of the cooling system with a new radiator, water pump, thermostat and hoses, things have been back to normal and the new fan clutch kicks ass.

 

[brooks202]

I had terrible luck with the "stock" red AISIN fan clutches on my FJ62. They never seemed to engage when I needed them and when they did, it was kind of weak and they would kick off too easily. Check out my old thread about picking up a light blue fan clutch for an FJ80 (I think) and tuning it. The light blue clutches have an adjustable spring in front that lets you change what "temperature" they engage at, and you can even change out the fluid inside the make it lock up harder and stay on longer. I did both on mine, adjusted the timing of that engagement spring and added a much heavier silicone fluid inside and it works fantastic now. Pulls much more air than an electric fan ever would at full tilt. I had a couple issues with running hot that were probably related to poor maintenance on my end but the fan helped the most significantly. Since taking a thorough refresh of the cooling system with a new radiator, water pump, thermostat and hoses, things have been back to normal and the new fan clutch kicks ass.

Thanks so much I finally got the 80 series blue clutch and yesterday decided to just test if it would work without any adjustments- nope. Now im gonna get that thicker oil and adjust the engagement screw. Fingers crossed!
Do you think I could get away with just opening it and adjusting it without buying any new fluid? (I've read that long thread a few times but don't remember if that was an option) just in case some comes out would this be a good place to get more ?Genuine Toyota Fan Clutch Silicon Oil 08816-03001 | Frontier Toyota - https://parts.frontiertoyota.com/oem-parts/toyota-fan-clutch-silicone-oil-881603001
Thanks for the help

 

[brooks202]

I think I'm gonna go with this stuff

Mugen Seiki Silicone Differential Oil (50ml) (15,000cst) [MUGB0337BA]

Oil Overview: This is a 50ml bottle of Mugen Silicone differential oil for 1/8th scale off road buggies (and some 1/10th scale on-road touring cars).... MUGB0337BA

www.amainhobbies.com

Someone on mud suggested it so thats good enough for me. Few tubes oughta be plenty.

 

[Mark W]

Back up and take a breath. You might be chasing that dead horse up the wrong tree. or something like that.

Let's start by answering one important question. Is the fan clutch engaging or not? If it is... then, well it is and it is not your problem. Yep, the performance of the Asian fan clutch can be adjusted and can be improved. But a run of the mill 2F in a nominal FJ60 doesn't need anything but a run of the mill nominal OEM fan clutch.

Warm the rig up. Get it hot. Pop the hood, lean over and blip the throttle. if the fan clutch is locked, you will get blasted in the face with a HARD gush of air. Then turn the engine off. if the fan stops with the engine, it is locked.

If you just barely get a little breeze when you blip the engine and if the fan freewheels when you turn the engine off. It ain't locked.

Make this determination before you put more effort into diving down the "modify my fan clutch" rabbit hole.


A missing thermostat O-ring will not keep your thermostat from opening. It *might* delay the opening some until the un-metered coolant flow around the thermostat is not enough to keep the engine coolant temps below the thermostat rating. But once the temp comes up, it will open.

It will delay warm up and severely reduce the capability of your heaters. Replace the darn thing already.

A clogged radiator will cause overheating. A deteriorated head gasket or a cracked head will cause over heating. Both will cause a loss of fluid (which a bad fan clutch can not do).

A clogged catalytic converter will cause overheating. Retarded timing will cause overheating. Both of these will also affect engine performance though and this will usually be noticable.


So... Are you positive that your fan clutch is or is not engaging? If it is engaging and you are overheating... the problem is not the fan clutch. Under normal operating conditions with a normal engine the fan clutch is not operating on any sort of knife edge balance where you need to tune adjust and modify it to keep the engine cool.


Mark...

 

[OSS]

I’m with Mark here. The overheating problem isn’t because of a faulty fan clutch.
The bi-metallic thermosensor in the center of the clutch opens or closes a valve inside the clutch to allow or stop the oil in the clutch from migrating. If that sensor doesn’t get hot enough air, the clutch won’t lock up.

If the engine is overheating but the fan clutch won’t lock up, that’s pointing to the coolant flow and air flow through the radiator — the air flowing through the radiator isn’t that hot, or the coolant isn’t flowing fast enough.

My guess: this may be a radiator problem, or water pump- not the fan clutch.

The nuclear option? Replace the radiator and water pump. I’ve seen pictures of FJ60 water pumps almost completely clogged with some sort of goo.

Speaking of goo ——-
I ran into a persistent overheating problem that I could not track down the cause.

Eventually I discovered why the engine was running hot —— the small coolant passages in cylinder head were completely clogged with goo - blocking the coolant flow through the head.

Where did this goo come from?
Many many years ago I used orange Dexcool coolant during a coolant change (this was before the internet) and that crap creates goo in the engine if any green coolant remains.
Surprise!

 

[brooks202]

Warm the rig up. Get it hot. Pop the hood, lean over and blip the throttle. if the fan clutch is locked, you will get blasted in the face with a HARD gush of air. Then turn the engine off. if the fan stops with the engine, it is locked.

If you just barely get a little breeze when you blip the engine and if the fan freewheels when you turn the engine off. It ain't locked.

Yea I can confirm that all three clutches do not engage- the engine is very quiet and they only engage after sitting at a stop light for a few seconds or at startup. If I paracord the fan to the water pump pulley then the engine doesn't overheat (maybe 3/4 up the temp gauge after hours of driving on a hot day). Also the newspaper test stops the fan with engine extremely hot. I'm pretty sure the clutch is getting enough heat because the IR gun shows a hot radiator and a towel will stay held up against the grill so theres plenty of air flowing and a functional shroud.

A missing thermostat O-ring will not keep your thermostat from opening. It *might* delay the opening some until the un-metered coolant flow around the thermostat is not enough to keep the engine coolant temps below the thermostat rating. But once the temp comes up, it will open.

It will delay warm up and severely reduce the capability of your heaters. Replace the darn thing already.

Understood Ill get it done

A clogged radiator will cause overheating. A deteriorated head gasket or a cracked head will cause over heating. Both will cause a loss of fluid (which a bad fan clutch can not do).

This is interesting because I was worried about the head gasket. My coolant does disappear and get dirty (oil looks clean but haven’t checked under valve cover just dip stick) but doing a pressure test showed its just escaping through the rear heater lines and after I get the parts to replace those hoses I will see if she holds pressure (I was pumping it to 17psi or so and it would go down to below 15psi within ~7mins). This made me worry about the head gasket but several exhaust hydrocarbon tests on the radiator all stayed blue. Thank God. This makes me think the coolant may be getting contaminated through the oil cooler or may just be some rust/goo in the engine that needs to be cleaned out.
Also my heater core has always made the empty soda cup straw suck sound when I turn up the heat. So it has air in it meaning maybe its rusting from the inside?

In terms of the radiator it's only a few years old and I flushed it this summer. I got a new water pump and radiator flush in my garage if need be but both upper and lower rad hoses seem plenty hot and pressurized so I think its okay.

Retarded timing will cause overheating

I made the mistake of having a relatively good mechanic do emissions testing for me in the spring and I'm pretty sure they forgot to de-tune the engine! My idle is still at a thousand vs 600 before and with my timing light I can't see the marking I made on my flywheel for the BB hole. I'm thinking they forgot to bring down the timing and it's still somewhere crazy like 14 degrees (Ive read people do that at this elevation but I don't wanna push it). I'll sort all that out down when I do my valve adjustment but I was doing the fan clutch first.

Many many years ago I used orange Dexcool coolant during a coolant change (this was before the internet) and that crap creates goo in the engine if any green coolant remains.

I've definitely mixed coolants in the past and might have caused something like this... Should I just flush the coolant system a bunch of times and see if that fixes it?

One last note: I'm not able to identify if my oil is leaking into the coolant or if it's something else because my oil pan leaks a quart every 2 months. I just got a new cork gasket in the mail and will get that replaced but I figured if my head gaskets blown why worry about the oil pan

Thanks for all the help

 

[brooks202]

Update: Im starting to suspect the radiator is the issue. I idled the engine for 15mins and took some measurements of temps around the radiator. The temp gauge was 3/4 to the top and the bolt holding the thermometer wire was 145 degrees F.
The radiator fins and fan clutch bimetallic coil were only warm! I'm thinking my radiator might be clogged because the right side (facing the engine from the grill) is much hotter than the left side and theres a nasty impact area on the top right (just noticed)

Here's my temp readings (right=drivers side)
Top rail radiator: Right=111F,Left=81F
Fins:
Top right=118,Top left=85
Bottom right=116
Bottom left=90
Center fins in front of fan clutch=103
thermostat housing=150

Here's whats interesting though- both upper and lower rad hose are 105 degrees.

So maybe the radiator is clogged or bruised and only passes coolant through the right side. My other theory is the water pump may have something wrong with it because I'm not able to feel the "pressure surge" when squeezing the top hose with engine running.

Here's some not so useful pictures (ignore the splash of coolant everywhere I was checking the level to burp the system and it had pressure in it so when I turned her on the fan sprayed It everywhere)
Top radiator rail:

Upper and lower hoses

Edit: Eureka! This also might be happening because the radiator core isn't full of coolant from when I did the hydrocarbon test because I needed a few inches of air at the top. This could be causing the coolant to only flow from the right side where the hose supplies it down the tubes on the right before the left side gets any keeping that side of the radiator just full of air. I'll fill it all the way and burp it and try again.

 

[brooks202]

Propped up front passenger side and burped her for a good half hour and temps stabilized across the fins. I drove up the mountain road (never got very hot but then again its snowing out) and at the pullout the fins were a good 170 degrees and the bimetallic coil was too hot to touch yet the fan wasn't engaging and with the engine off it spun freely. The heat sink around the fan clutch was a good 140 degrees (cant point the temp gun directly at the coil). Glad my radiator isn't the issue. Upper rad hose 140 lower hose 110.
Fan clutch mod coming this weekend

 

[brooks202]

Finally resolved the issue! First blue clutch wouldn't work despite adjustments so had to wait for replacement.
I got her warmed up in the oven to drain to the water pump side so when I disconnected it the coil side was dry

Then I drained the other side in the oven while I made the adjustments on the stove up top

Put it in a small sauce pan on a cloth to keep the coil from directly touching the pan and slowly heated up- picture shows hole completely open after getting it too hot without opening much and adjusting the plate.

Initially the plate was set to stay closed until the inside of the fan clutch was around 140 degrees (coil was hotter) but after adjusting it as far as it would go I can confirm when the bimetallic coil gets around 100* the hole opens half way- good enough for me.

It's freezing and snowing outside so I had to take it on a 40 minute drive up the mountains but right when I began to lose hope she kicked in and stayed on. What a relief. My cruiser has now had 5 fan clutches

Thanks all for your help keeping another cruiser on the road!
Here's a pic of mine and my buddies reunited at last- mines the tan one.