Fan Clutch rebuild resource?

[tucson_sailors]

In the thread about rebuilding the fan clutches, it was mentioned in how delicate the sealing ring was, and that it had a square or rectangular cross section. Wonder if this is what they are using? Comes in various materials, and seems to be in the right temp range.

I'm going to be pulling apart a spare clutch here before too much longer for my 2F, I'll get the measurements if someone doesn't already have it available, and then order the most heavy duty square o-ring I can, and see how it works.

Allied Seals Orings, Cord Stock, Square, Lathe, Spliced, Viton

and

http://www.theoringstore.com/servlet/the-5281/026-Buna-70-O-dsh-rings/Detail

Glenn in Tucson

 

[Tools R Us]

In the thread about rebuilding the fan clutches, it was mentioned in how delicate the sealing ring was, and that it had a square or rectangular cross section. Wonder if this is what they are using? Comes in various materials, and seems to be in the right temp range.

I'm going to be pulling apart a spare clutch here before too much longer for my 2F, I'll get the measurements if someone doesn't already have it available, and then order the most heavy duty square o-ring I can, and see how it works.

Allied Seals Orings, Cord Stock, Square, Lathe, Spliced, Viton

and

The O-ring Store - Online O-rings, O-ring Kits, Oring Seals, Oring Lube, and Oring Assortments

Glenn in Tucson

The o-ring is pretty durable. The biggest "problem" is stretching, be careful when cleaning it. I have never had to replace one, but don't think the square profile is important, a properly sized round one would likely work fine.

 

[tucson_sailors]

Pliability of oring

The o-ring is pretty durable. The biggest "problem" is stretching, be careful when cleaning it. I have never had to replace one, but don't think the square profile is important, a properly sized round one would likely work fine.

I would suspect being constantly in contact with the silicone would keep it springy. Just figure its worth getting spares for the inevitable time one of the darn things tears.

Read on some other forum (Porsche 928) that they cut the ring, to resize due to stretching, and use a small dab of RTV to put it back together. Would prefer to have new rings in reserve, rather than have to bodge it, if at all possible.

Did you find the 20,000cst or 30,000cst to be the best for the 'extreme conditions' that are AZ? Looking for one that occasionally (winter) unlocks at room temp, but since I'm not FI on my 60, no worries if it runs a bit cooler with higher viscosity fluid. Goal is to have the a/c on at a stop light for an extended sit, and not have temp creep.

Glenn

 

[Tools R Us]

I would suspect being constantly in contact with the silicone would keep it springy. Just figure its worth getting spares for the inevitable time one of the darn things tears.

My guess is the silicone causes it to slightly swell, possibly somewhat causing the stretching? I have never had one tear. Depending on clutch type, etc, the o-rings are different sizes, so would need to open it and measure to determine the proper size.

Read on some other forum (Porsche 928) that they cut the ring, to resize due to stretching, and use a small dab of RTV to put it back together.

I have only had to sectioned a couple, to large to fight back in. Just cut it at a pretty good angle and used super glue. Super glue is what is used in the universal o-rind making kits, works great, as long as the ring is clean.

Did you find the 20,000cst or 30,000cst to be the best for the 'extreme conditions' that are AZ? Looking for one that occasionally (winter) unlocks at room temp, but since I'm not FI on my 60, no worries if it runs a bit cooler with higher viscosity fluid. Goal is to have the a/c on at a stop light for an extended sit, and not have temp creep.

Glenn

I don't have much experience with the '60 clutches, so some experimentation will be needed to get working how you want it. They are very similar to the 22R clutches, so would try in the 15K range and see how that works. My fill would be ~35-40ml depending on how empty/clean it is.

As long as it's not overfilled, it will turn off when not needed, when it has cool radiator airflow. Cool weather operation isn't an issue and the motor minimum operating temp is controlled by the coolant thermostat, so when setup properly, it should run slightly over thermostat opening temp in all conditions.

 

[Tools R Us]

Have you read this thread, it gives a pretty good overview?
https://forum.ih8mud.com/79-95-toyota-truck-tech/167678-fan-clutch-service.html

When draining I stand it up in a pan. It's important to have one of the drain holes in the front/reservoir half at the bottom so it can fully drain. Placing it out in the sun helps with drain time.

 

[tucson_sailors]

Eureka!

Have you read this thread, it gives a pretty good overview?
https://forum.ih8mud.com/79-95-toyota-truck-tech/167678-fan-clutch-service.html

When draining I stand it up in a pan. It's important to have one of the drain holes in the front/reservoir half at the bottom so it can fully drain. Placing it out in the sun helps with drain time.

Yup. That was the one I was thinking of - you can see the o-ring in there that was damaged in taking it apart, I believe. I had remembered that the square o-ring was not an item available from Toyota, so for those times where it would be needed, I'm thinking finding the dimensions and suppliers would be something to put in the 60 forum, but wanted to pass along to CSC in general since not all of the later models use pure electric fans, and might get some use out of the data as well.

Glenn

 

[Tools R Us]

Yup. That was the one I was thinking of - you can see the o-ring in there that was damaged in taking it apart, I believe. I had remembered that the square o-ring was not an item available from Toyota, so for those times where it would be needed, I'm thinking finding the dimensions and suppliers would be something to put in the 60 forum, but wanted to pass along to CSC in general since not all of the later models use pure electric fans, and might get some use out of the data as well.

Glenn

I have the design sheets for proper o-ring selection, when you take one apart measure the groove and I will help with the part numbers.

None of the Toyota trucks that I have seen have electric primary fans. Clutch fans are much more powerful and reliable than electric, so are preferred where reliability and simplicity are needed, like on an off-road rig.