[Zukk390]

Hi all, have a seirra 1990 has a 1.6L in it. Just purchased a new radiator for it. Have heard putting a vitara fan in it will be better for cooling?
Also has the orginal viscous how can I test it? If did need replacing do I put another seirra in it or put vitara?

Thanks!

[Gwagensteve]

A 1990 Sierra does not have a viscous fan.

[Zukk390]

It definitely has one, could it be vitara then?

[Zukk390]

It definitely has one, could it be vitara then? Can't load image file too big

[Beery]

what 1.6L does it have in it? chances are it's out of a Vitara, so you probably already have a Vitara viscous fan.

A sierra is a solid fan from factory. Here's a comparison between the two:

[sideways]

In terms of testing the hub, get the motor up to operating temperature (82 degrees, or thereabouts) and shut it off. The fan should stop as soon as the motor does, if it keeps on freewheeling then that's not good enough for 4wd use. It either needs new/more oil or the hub replaced. Check if it's been leaking oil around the spiral spring on the front and check that the spring isn't broken or has come out of its notch.

Fwiw I bought one of the cheap eBay hubs and it worked great but started to leak out its oil after about a year. I replaced it with a more expensive "made in Japan" (Tora I think) one which has held up fine for the last few years but has a pretty weak lockup so can heat up on sand a bit. I should really pull it down and put some more oil in it.