fan clutch / other oil alternatives

Supra

New Member
May 11, 2005
304
0
0
48
Rockford, IL
figgie said:
well depends on what you were looking for

I know that they sell silicone fluid for the shocks in RC cars. From 10 weight to 150 weight. I used 30 weight in my RC-10 when I raced and that was way to light for fan clutch duties. minimum of 80 weight to work right.

I think Jetjock posted that info, but has deleted his post. :3d_frown: I see a quote of part of it in another post on page 1.
 
Oct 11, 2005
3,816
13
38
Thousand Oaks, CA
The correct amount for a bone dry clutch is 3 bottles. For mine, when I refilled I just attempted to drain the old oil out by gravity for a few hours. Then I put 3 bottles in and it was 'on' all the time hot or cold. Used a syringe to get 18mL out and now it works fine.

I assume I didn't get all the old oil out and had probably a bottles worth still in it when I added the new stuff.

You can see the bimetal strip rotate the internal valve plate when you heat it with a hot air gun. If you pull the clutch apart you will see a ring of internal fluid holes that get covered up when cold and open when hot.

By the way, the blue flange is factory.
 

johnathan1

Supra =
Aug 19, 2005
5,056
1
36
35
Downey, California, United States
Thanks 3p!! I wish there was still rep!

Is it possible for the bimetal strip to stop working? My clutch won't disengage at all now that i put new fluid in it...I filled it to the same level that the old fluid was at, the fluid was just dark and brown...can the fluid get worn out?
 
Oct 11, 2005
3,816
13
38
Thousand Oaks, CA
The bimetal strip will not wear out, but it can break. Also, the shaft can seize up due to corrosion.

Dark brown fluid would worry me. My stuff was clear when I opened it up. Maybe it overheated?
 

johnathan1

Supra =
Aug 19, 2005
5,056
1
36
35
Downey, California, United States
I took off my fluid coupling a few more times, and drained out fluid by about 10ml the first time, and 10ml the second time, It scared me a bit, because by this point, there was hardly any fluid in it, and it was still resisting more than it should, and the resistance doesn't change no matter what the temp is, however, the bimetal strip does turn, and the internal valves move...so I have no idea what the problem could be...I guess I'll have to find another clutch. :(

Oh, and BTW, I think that it is very possible that the fluid could have become overheated, this clutch has been through at least one BHG that I know of.
 
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Oct 11, 2005
3,816
13
38
Thousand Oaks, CA
I suspect you still have a lot of oil trapped inside it. You need to flush it out and start fresh. There are a few silicone oil solvents out there, but you might try brake cleaner to start as I have heard it will work (YMMV).

It is possible the bearing is gone, and it may be simpler just to find another clutch though.
 
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