D22 Viscous fan hub oil
- Thread starter Jardsoooo
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No idea of the required quantity, but I bought a bottle from Toyota ($18, but that was a few years back) and just poured the whole thing in. It's been working perfectly ever since, although I do suspect it's starting to "lose its edge".
Jardsoooo
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Thanks for your reply Tony. I'm assuming your hub was'nt fully engaging thus your bus was running hotter under load ?
Was there evidence of oil loss ?
Are you confident the fan is engaging and disengaging as required ?
My girl began to heat up under load - eg a long climb towing a trailer.
And once the gauge ( standard factory ) started climbing it was climbing quickly, resulting in a couple of down changes ( manual ) till it stopped climbing.
Cresting the hill the gauge was dropping almost immediately to normal.
Radiator guy reckoned good chance it was the fan hub.
I took it over to him and his off sider pulled it apart and wacked in some more oil.
I was'nt sure about it as there was no visible oil loss and the shaft was demonstrating a decent amount of resistance but thought it was worth a try.
Good news is it fixed the overheating - bad news is the fan would'nt disengage.
In terms of the overheating alone , having the fan locked on could be just masking the primary issue eg an under performing radiator so I was really none the wiser.
Not to mention the fan noise and power loss.
I decided to to just buy a new hub and be done with it to end the dicking around.
Well - the new hub is'nt disengaging either ! - not fully - going on the noise, I'm calling it at 70% engaged still, and to get that level of disengagement the gauge has to be pretty well up to operating temp - not far from the point it should be starting to engage !
So back to the old hub I've pulled it apart and drained the oil so I was hoping to be able to put the correct quantity back it and see if I can make it operate correctly.
Thus my question.
Incidentally - I placed the front half of the hub - the half with the thermostat - over a tin of water and heated it up to boiling to check it's operation and the oil gate opened fully so I feel confident I can discount that. I've got pics if anybody is interested in the inner workings of a fan hub.
Was there evidence of oil loss ?
Are you confident the fan is engaging and disengaging as required ?
My girl began to heat up under load - eg a long climb towing a trailer.
And once the gauge ( standard factory ) started climbing it was climbing quickly, resulting in a couple of down changes ( manual ) till it stopped climbing.
Cresting the hill the gauge was dropping almost immediately to normal.
Radiator guy reckoned good chance it was the fan hub.
I took it over to him and his off sider pulled it apart and wacked in some more oil.
I was'nt sure about it as there was no visible oil loss and the shaft was demonstrating a decent amount of resistance but thought it was worth a try.
Good news is it fixed the overheating - bad news is the fan would'nt disengage.
In terms of the overheating alone , having the fan locked on could be just masking the primary issue eg an under performing radiator so I was really none the wiser.
Not to mention the fan noise and power loss.
I decided to to just buy a new hub and be done with it to end the dicking around.
Well - the new hub is'nt disengaging either ! - not fully - going on the noise, I'm calling it at 70% engaged still, and to get that level of disengagement the gauge has to be pretty well up to operating temp - not far from the point it should be starting to engage !
So back to the old hub I've pulled it apart and drained the oil so I was hoping to be able to put the correct quantity back it and see if I can make it operate correctly.
Thus my question.
Incidentally - I placed the front half of the hub - the half with the thermostat - over a tin of water and heated it up to boiling to check it's operation and the oil gate opened fully so I feel confident I can discount that. I've got pics if anybody is interested in the inner workings of a fan hub.
I was experiencing the same (towing our 2.5T caravan up hills). Sometimes the problem is made worse by a radiator that's partially blocked.
You can hear the fan when it's coming on strong. There's a quite distinctive rushing sound - it's quite noticeable, and particularly when it's disengaging because that's when the engine power is reduced because you're coasting downhill as the temp drops.
The bimetal coil that engages the fan is supposed to lock on at 91 degrees (the manual defines this temperature as the test point for the valve).
Mine is not completely accurate in terms of engagement temperature. My cruise temperature on level ground when towing is about 94C and you'd expect the fan to be engaged then - it seems to come on at about 96C. It will disengage at around 90C.
You don't want the fan engaging fully too early - the thermostat isn't fully open until about 85C and until 85C, your glow plugs are still active. My cooling system is effective enough to bring the coolant temps down to 83C on a long downhill - it never stays there long, and I'm not inclined to mess with it to change that.
I am considering a more efficient radiator. The thinking goes like this: I'm using a certain amount of fuel to keep the revs at a particular level, and if I have to use a lower gear (to reduce the engine load to reduce temps) then I'm not getting as much speed - which means I'm covering less distance for the same amount of fuel being used. If I can keep my speed a little higher, I'm covering more ground for the same fuel so my overall consumption for the trip will be less and that's money in my pocket instead of big oil's pocket.
You can hear the fan when it's coming on strong. There's a quite distinctive rushing sound - it's quite noticeable, and particularly when it's disengaging because that's when the engine power is reduced because you're coasting downhill as the temp drops.
The bimetal coil that engages the fan is supposed to lock on at 91 degrees (the manual defines this temperature as the test point for the valve).
Mine is not completely accurate in terms of engagement temperature. My cruise temperature on level ground when towing is about 94C and you'd expect the fan to be engaged then - it seems to come on at about 96C. It will disengage at around 90C.
You don't want the fan engaging fully too early - the thermostat isn't fully open until about 85C and until 85C, your glow plugs are still active. My cooling system is effective enough to bring the coolant temps down to 83C on a long downhill - it never stays there long, and I'm not inclined to mess with it to change that.
I am considering a more efficient radiator. The thinking goes like this: I'm using a certain amount of fuel to keep the revs at a particular level, and if I have to use a lower gear (to reduce the engine load to reduce temps) then I'm not getting as much speed - which means I'm covering less distance for the same amount of fuel being used. If I can keep my speed a little higher, I'm covering more ground for the same fuel so my overall consumption for the trip will be less and that's money in my pocket instead of big oil's pocket.
