Aisin FCT-049 fan clutch (2 Viewers)

[Godwin]

I've recently gone through most of my cooling system, new CSF radiator, Aisin water pump, OEM radiator cap. Did not change out the thermostat because it has been working properly. I also reused the fan clutch that's been in a few years. With the warming temperatures I was seeing water temps around 210F at speeds > 60 mph so I decided to swap in a new fan clutch. I went with the Aisin FCT-049 which is for a 3FE in the FJ80. I've read this is an upgrade over the 2F fan clutch.

Installed the new fan clutch and saw no difference in water temps at interstate speeds. Swapped the old fan clutch back in, which also is a FCT-049 and last was working ok. Today I split open the new fan clutch to replace the silicone oil. I went with 10,000 weight and used one bottle. I also noticed that the fan clutch is adjustable.

The setting out of the box is with the screws set far left in the slot. I loosened and reset to far right. I'll swap the modified fan clutch in later this week to see if these changes make a difference.

The pedestal of the FCT-049 is a sage green.

 

[OSS]

If the stock fan clutch can’t keep the engine cool, no matter how hot it is outside or how hard the engine is being pushed, there’s an underlying problem that’s creating excessive heat.
When the engine is running properly, the standard fan clutch is more than adequate.
The standard fan clutch is the messenger. Don’t kill the messenger. It’s trying to tell you something.

 

[toy_tek]

I've recently gone through most of my cooling system, new CSF radiator, Aisin water pump, OEM radiator cap. Did not change out the thermostat because it has been working properly. I also reused the fan clutch that's been in a few years. With the warming temperatures I was seeing water temps around 210F at speeds > 60 mph so I decided to swap in a new fan clutch. I went with the Aisin FCT-049 which is for a 3FE in the FJ80. I've read this is an upgrade over the 2F fan clutch.

Is this with AC on or off?

The setting out of the box is with the screws set far left in the slot. I loosened and reset to far right. I'll swap the modified fan clutch in later this week to see if these changes make a difference.

Interesting. I've never had one apart, how do you know changing the position is going to increase the cooling effect rather than decrease it?

If the stock fan clutch can’t keep the engine cool, no matter how hot it is outside or how hard the engine is being pushed, there’s an underlying problem that’s creating excessive heat.
When the engine is running properly, the standard fan clutch is more than adequate.
The standard fan clutch is the messenger. Don’t kill the messenger. It’s trying to tell you something.

Can you be more specific? What temperatures exactly? He didn't say he overheated, just that it runs hot. My 3FE does the exact same thing when its 105+, and I've replaced everything in the cooling system, as well as added the FCT-049. I saw 215-220 just today on the way home, which is normally what I've been seeing in summertime for the last 4 years since I got the truck. But it never actually overheats, the factory temp gauge never goes into the red. [edit} all other engine parameters are normal/correct: timing, recent tune up, good compression, passed emissions, etc. FWIW, I'm in Phoenix.

 

[BamaHeel]

It’s been 100+ in Alabama the past week not counting humidity. I believe @Godwin has a handle on it.

Last Friday at GSMTR in TN it was so hot that the heat combined with trail braking I boiled my brake fluid and had to replace it.

 

[Godwin]

Is this with AC on or off?


Interesting. I've never had one apart, how do you know changing the position is going to increase the cooling effect rather than decrease it?



Can you be more specific? What temperatures exactly? He didn't say he overheated, just that it runs hot. My 3FE does the exact same thing when its 105+, and I've replaced everything in the cooling system, as well as added the 80 series fan clutch. I saw 215-220 just today on the way home, which is normally what I've been seeing in summertime for the last 4 years since I got the truck. But it never actually overheats, the factory temp gauge never goes into the red. FWIW, I'm in Phoenix.

No AC. I use my natural cooling system and just sweat.

I have an Autometer temp gauge plugged in for about 250k miles. Normal operational water temp, whether winter or summer, is 195F, and it will remain at this temp if running <60 mph. In the photo I'd been running >65 mph for miles. It held steady at this temp. I suspect the fan clutch because I never hear it kick in. I also have a 3FE swapped FJ60 and have seen the fan clutch kick in when water temps rise while running highway speeds in the summer. You can hear the fan clutch and see watch as the stock temp gauge drops as the water temp is pulled down.

 

[Godwin]

If the stock fan clutch can’t keep the engine cool, no matter how hot it is outside or how hard the engine is being pushed, there’s an underlying problem that’s creating excessive heat.
When the engine is running properly, the standard fan clutch is more than adequate.
The standard fan clutch is the messenger. Don’t kill the messenger. It’s trying to tell you something.

The messenger has been mute which is why I'm trying this approach.

 

[Godwin]

Interesting. I've never had one apart, how do you know changing the position is going to increase the cooling effect rather than decrease it?

I don't but will find out.

 

[John McVicker]

Subscribed. Very interested in your comparison results with the 10k silicone.

In 2018 I also switched to the green FCT 049 & saw a marked improvement over the stock FCT 017, but have been debating putting in some heavier silicone for even better performance.

Looking forward to what you learn.

 

[4runner2FJ60]

Nice write up. I like your aftermarket gauges, I think I have the same great radio! Curious also about the adjustments you did.

 

[OSS]

As another data point. Toyota sold a water pump to fan assembly for the 2F without a provision to use a viscous fan clutch at all. The fan is directly bolted to the water pump with no clutch. These were used on land cruisers used as mining work trucks in other countries. Yes, they roared like hell at highway speeds but these vehicles weren’t intended for typical passenger vehicle use.

 

[toy_tek]

No AC. I use my natural cooling system and just sweat.

I have an Autometer temp gauge plugged in for about 250k miles. Normal operational water temp, whether winter or summer, is 195F, and it will remain at this temp if running <60 mph. In the photo I'd been running >65 mph for miles. It held steady at this temp. I suspect the fan clutch because I never hear it kick in. I also have a 3FE swapped FJ60 and have seen the fan clutch kick in when water temps rise while running highway speeds in the summer. You can hear the fan clutch and see watch as the stock temp gauge drops as the water temp is pulled down.

Ok, my similar temp is with the AC on, I'll see a 5-10 degree drop if I turn the AC off.

I have the same Autometer gauge. We have very similar temp performance... I see 190-195 the rest of the year pretty solidly. I can hear my fan clutch when I'm pulling away from a red light or stop sign... it roars for 10-15 secs then quiets down. So I know it works correctly... VERY infrequently I'll hear it on the highway but the temps are easily 225+ at that point. Again, my truck has never overheated. But it sure runs hot.

I was hoping @OSS could shine some light on normal operating temp range for the 3FE as well as the fan clutch specifics.

 

[Godwin]

Nice write up. I like your aftermarket gauges, I think I have the same great radio! Curious also about the adjustments you did.

In the 80 series forum there are discussions about adjustable fan clutches and when I opened this one and noticed the set screws I decided to try adjusting it.

 

[cruisermatt]

What’s wrong with 210F?

 

[toy_tek]

Can you be more specific? What temperatures exactly? He didn't say he overheated, just that it runs hot. My 3FE does the exact same thing when its 105+, and I've replaced everything in the cooling system, as well as added the FCT-049. I saw 215-220 just today on the way home, which is normally what I've been seeing in summertime for the last 4 years since I got the truck. But it never actually overheats, the factory temp gauge never goes into the red. [edit} all other engine parameters are normal/correct: timing, recent tune up, good compression, passed emissions, etc. FWIW, I'm in Phoenix.

Ok so I might have partially answered my own question. Did a little digging in the 1989 FSM, really the only mention of upper temp limits are in relation to the radiator cap and the thermostat. It doesn't address when the stock fan clutch should turn on or off however.

Radiator cap: "the relief valve opens and lets steam escape through the overflow pipe when the pressure generated inside the coolant system exceeds the limit (coolant temp 230-248F)

Thermostat (paraphrasing) : starts to open at 191F. full open at 212F - and valve lift should measure 10mm or more.


So I guess normal hot operations could be anywhere between 191 and perhaps upwards of 230. I suppose the challenge at that upper point becomes: is the system able to maintain cooling or does the system temp run away and overheat.

So far, mine has been able to keep the cooling system from boiling over.


EDIT 7-2-22
Also... not sure if this info is pertinent to this thread exactly... but it is somewhat related.

When I rebuilt my cooling system 3+ years ago, evidently I installed an Aisin 180* thermostat, which I had subsequently forgot about and (more recently) could not find my receipt to confirm what part number I used. Admittedly I did not do much research on that at the time, just figured it would make the truck run cooler. Well, it did what I described earlier.

Yesterday I removed the 180* and installed the correct OEM 190* unit (90916-03052).

Not surprisingly, the running temp was slightly higher (Phoenix summer, AC on, side streets mainly) so somewhere between 195-205.

What did surprise me though, is that now my fan is kicking on around 205 deg and staying on until the temp remains or drops below 205 Previously I would only ever notice the fan come on if the temp showed 220+ or if I was sitting at idle and then taking off from a stop.

This tells me that I'm getting more hot water flowing through the radiator than with the 180* thermostat.

Since I made no other changes to my system, I'm basically able to confirm info I've seen in other threads that the 190* OEM thermostat is better for controlling the water flow through the radiator.

@Godwin you said you didn't replace your t-stat - are you able to confirm if it is an OEM 190*? if not, this could be part of your solution.

 

[Godwin]

I installed the modified fan clutch today and will be giving it a good test tomorrow and Saturday when I do a couple interstate runs at 70 mph with air temps hovering around 100F.

 

[Godwin]

Ok so I might have partially answered my own question. Did a little digging in the 1989 FSM, really the only mention of upper temp limits are in relation to the radiator cap and the thermostat. It doesn't address when the stock fan clutch should turn on or off however.

Radiator cap: "the relief valve opens and lets steam escape through the overflow pipe when the pressure generated inside the coolant system exceeds the limit (coolant temp 230-248F)

Thermostat (paraphrasing) : starts to open at 191F. full open at 212F - and valve lift should measure 10mm or more.


So I guess normal hot operations could be anywhere between 191 and perhaps upwards of 230. I suppose the challenge at that upper point becomes: is the system able to maintain cooling or does the system temp run away and overheat.

So far, mine has been able to keep the cooling system from boiling over.

Similar temps are given for the 2F except a range is given, 187-194F, and fully open at 212F with same valve lift. I couldn't find any info in the 1980 2F engine manual about coolant system limits but given the similarities between the 2F and 3FE the upper limits may be comparable.

 

[toy_tek]

I installed the modified fan clutch today and will be giving it a good test tomorrow and Saturday when I do a couple interstate runs at 70 mph with air temps hovering around 100F.

Any update?

 

[reddog90]

I needed to replace my water pump so I went ahead and installed this fan clutch at the same time. Will have an update next week. I didn’t have overheating problems before this but my red base clutch looked original and I didn’t want to go back in there anytime soon.

 

[Godwin]

Any update?

Results thus far are inconclusive. I made one drive at 65-70 mph and saw a decrease of about 10F in temperature, but a second drive pulling a boat had the water temps back up to 210. I'm going to open up the fan clutch and readjust following the method described in this threas Blue fan clutch mod...Thread has gone to hell, read at your own risk - https://forum.ih8mud.com/threads/blue-fan-clutch-mod-thread-has-gone-to-hell-read-at-your-own-risk.102633/

Doesn't take long to remove and tweak the fan clutch but the worst part is juggling the fan nuts in and out of the tight confine.

 

[OSS]

I don’t think an oil filled fan clutch should engage at all at 65 mph. And if it did, it wouldn’t likely do anything anyway- there’s a 65mph hurricane blasting through the radiator at that speed without any fan.