3.5 engine: Anyone knows how to put Toyota silicone oil in fan clutch? - PeachParts Mercedes-Benz Forum

werminghausen · #1 12-19-2012, 09:24 PM

I want to try one thing to improve cooling in parallel. Fan clutch is sketchy on my 3.5. I think I could get Toyota silicone oil 10000 viscosity and can put it inside the clutch. Anyone tried this on our old visco clutch?
Any help is good.

engatwork · #2 12-19-2012, 09:31 PM

I want to say that I've seen a posting either on here or on the net of this being done and there were pictures with it.

Tomguy · #3 12-19-2012, 11:27 PM

I never figured how to on my 4.5 and I wouldn't be shocked if the 3.5 has the same clutch & it can't be done. Not all the vintage ones can have it done.

werminghausen · #4 12-20-2012, 02:36 AM

Quote:

Originally Posted by Tomguy

I never figured how to on my 4.5 and I wouldn't be shocked if the 3.5 has the same clutch & it can't be done. Not all the vintage ones can have it done.

Hi Tomguy....what makes you say:can't be done?
in principle if I can't get to the pin for some reason I could drill a small hole , refill and the close the hole?
Anyone did it?

compress ignite · #5 12-20-2012, 03:11 AM

K6JRF Auto Page

See his # 20 + 21 !!!

werminghausen · #6 12-20-2012, 06:03 AM

Quote:

Originally Posted by compress ignite

K6JRF Auto Page

See his # 20 + 21 !!!

That sounds really interesting!. I'll look into this.
I'll remove my clutch net days and I'll try to remove the BMS and find the pin.
I am sure I lost some oil already, I'll put some back and then I'll think about cutting the pin shorter for earlier engagement of the clutch.
Thanks again.

werminghausen · #7 12-20-2012, 02:43 PM

update: I removed the fan clutch and took the BMS out. I needed to bend both sides of the bracket that holds the BMS. The pin is 8.45mm long, dia 2.8 mm.

So there are 2 things I could try to do: 1) put more oil into the inner chamber and 2) shorten the pin slightly in order to engage the clutch at lower temps.

So what is the best way and location to inject oil into the inner chamber?

werminghausen · #8 12-20-2012, 11:04 PM

I am trying to understand how this clutch is working.

The clutch seems to 'lock' or 'bite' at a certain temperatures of the BMS (Bimetal strip)...say the air is hot from radiator (120C) and the BMS is bending outward letting the pin goes further out and then the clutch engages.

I measured that ping completely out means it sticks its head out by 2.2mm room temps- not sure if this changes at high temps)
If I push pin in as much as it would go it sticks out 0.4mm
This means that total displacement at room temps is 1.8mm

Assuming the clutch is working (the inner parts) then in theory with a slightly shorter pin the 'engaging courve' would be lowered entirely meaning the clutch would engage the same way but at lower temps of the BMS.

Questions:
1)Does clutch bite progressively with rising temps?..... I guess being at a max at pin fully displaced (pin out)? Did anyone see a graph of how it 'bites'
2) How is the inner gear working? what makes the clutch engage?
my assumption is that the silicone is used as it is not changing its viscosity over the temp range?
3) Knowing or not knowing how the thing works inside (2) it seems to be logic that the silicone level inside the chambers (in upright position installed) can't be higher than the center because if level were higher the silicone would drain through the center pin hole (There is maybe a 0.1mm play in the pin hole, which is the reason why this clutch should not be placed/stored in any other position than vertical.
Is this a correct assumption

So here where I need some answers:
How do I get the Toyota 10000 silicone inside and then how much?

Palolo · #9 12-20-2012, 11:23 PM

Now you have made me curious, too... I am tempted to dig in to mine, vs fit an electric fan.

(Must resist another project... Must resist...)

Links for your perusal...

Refill of viscous fan clutch pictures

http://www.benzworld.org/forums/r129-sl-class/1474495-viscous-fan-clutch-theory-operation.html

Jaguar V12 Fan Clutch

werminghausen · #10 12-21-2012, 01:38 AM

Thanks for the input.

Tapping a hole refill and put a plug screw in can be a concept.
Is there way to refill with the existing pin hole?
In the pics you see my syringe with a long needle. With the other instrument I could press down the metal strip that pushes the pin up in case this is locking the hole.
Do you see any chance to fill this way?

How viscous is 10000 Toyota silicone? Is it like grease or like gear oil?
I am asking in order to find out it I could use some silicone o-ring seal lube I have, but this is very viscous. If I turn the bottle upside down it takes around a minute unit reaches equilibrium, it is so viscous.

werminghausen · #11 12-21-2012, 03:42 AM

Quote:

Originally Posted by Palolo

Now you have made me curious, too... I am tempted to dig in to mine, vs fit an electric fan.

(Must resist another project... Must resist...)

Links for your perusal...

Refill of viscous fan clutch pictures

Viscous Fan Clutch Theory of Operation - Benzworld.org - Mercedes-Benz Discussion Forum

Jaguar V12 Fan Clutch

Hi Paolo,
I think the clutch can be done. Only things I still don't know for sure what is the best way to fill and how much. I also don't know about the fluid. I hope I can get the Toyota silicone.

benzworld was discussing that the pin is an on-off switch mean if pin is out the clutch in 'on' and bites?

werminghausen · #12 12-21-2012, 04:08 AM

Jag V12 : The innards (of clutch)were covered with viscous fluid -- a dark gray grease.
Anyone knows for sure what the original grease was?

werminghausen · #13 12-22-2012, 01:21 AM

Anyone here?

so the plan is to get some of the 10000 silicone oil (Toyota or from a RC toy shop- the differential oil)
I'll set a boring in the housing and tap (I'll use M4 I think) refill as much as is needed to fill it half way (in upright position as installed) then install M4 set screw with loctite.

best, Martin

werminghausen · #14 12-24-2012, 03:40 PM

I 'll pick up the Toyota 10000 oil tomorrow. I 'll drill the clutch (M4 thread) and will fill then close with set screw and loctite. How can I make sure that no chips will fall into the boring? maybe drill and tap overhead?

Benz Dr. · #15 12-24-2012, 11:17 PM

Sounds like a complete waste of time but if you have lots to spare then why not?

If the clutch is worn out it is a waste of time. BTW, it works on two seperate principals - temperature and speed. You have the temp parts sorted out but the speed part is just as important. When these things sieze up they can become very dangerous. I had one do that once and it blew all of the blades off the fan from centrifugal force.