over heating at 50+

Still over heating if driving above 50 miles an hour, not loosing water or when standing in traffic its fine, could it be head gaskit,? no water in oil or visa versa
Does any one know how to check wether it is the fan or the switch?

You don't say how old your Jimny is.

The old ones have a Viscous fan whilst the recent ones have an electric fan. I would guess that its the Viscous Fan one.

The Viscous oil gets tired or even leaks out over time meaning that the fan slips at high revs. If you can get hold of some cable ties it is possble to "lock" the outer part of the fan to the hub forcing the fan to turn all the time. This will increase the noise of the engine and affect economy at low revs but will tell you if the problem is the fan. Its pretty fiddly to get the ties in place.

The other test is to get it hot and then try stopping the fan with a rolled up newspaper. This is quite dangerous and exciting to do but if the fan can be stopped then the Viscous mechanism is broken.

Its not possible to fix the mechanism. I took mine apart and the oil escaped quicker than MP's when someone shouts "Whos expenses claim form is this?". I simply rebuilt the mechanism with a piece of cardboard jammed inside to stop it slipping and all my cooling issues went away.

martin

Thanks Martin,
I will try that this afternoon, I will let you know
how I get on later.I will try and get some photos on later as well
because I want to strip the bumpers off to make up some winch bumpers up but wanted to get the running stuff fixed first.
Ade.

oldsilver wrote:

Thanks Martin,
I will try that this afternoon, I will let you know
how I get on later.I will try and get some photos on later as well
because I want to strip the bumpers off to make up some winch bumpers up but wanted to get the running stuff fixed first.
Ade.

Did you fix this in the end?

It was the viscous fan I think that started the problem, Its caught me out a couple of times bioling over, now I have to change the head gasket. Water in the oil!.Don't let it get too hotlike I did.

Hi,

Hows the rad, clean or full of crud ( Fins ), sounds like you've still the plastic on, not rad related but the front cross member can get full of mud :ohmy:

Andy

i faced this problem with 1999 jimny
i changed the fan and the cooling liqued at the radiator and it ddnt work
at the end it was the radiator needs to be cleaned. salty stains enough to over heat the car
if your Jimny is quite old, try to clean your radiator before changing anything at the same time check other parts like our friends here said.

good luck

taken every thing apart just about to lift the head off in the morning, tried to get manual but the only one I could find was a disc I had to send for,(Rapid manuals). I got ready with head set and new timing belt.I just hope I can remember how to put it all back together now!timing marks ect.Not sure how to lift cam off what happens to cam followers ect thats why I was waiting for manual.I will let you know how I get on, at the moment I wish I had not started the bloody job. Also don't know if I should change bolts or not some people say yes and some say they don't bother.
If I had a sware box it would be full and I would be skint

funny enough I still do have plastic on, not quite full yet though.I was just about to take all the front off ready to make winch bumper and I thought about rock bumper as well,probibly make both and have a look, I will post some pictures when I am done.

Just got jimny back together running lovely, 2 miles down the road power went then cut out, fired up again 200 yards down road no power then cut out again, this carried on for about a 1/2 mile to the house.Temprature was normal but had not been running long, checked water full of oil, checked oil and full of water plus air filter box full of water, I suspect possible head cracked? although every thing looked fine when it was apart, does anyone kmow if it might be cracked where you cant see it somwhere? cant think of anything else it could be.
If so has anyone got a good head for sale? I think it just might need taken out and given a damb good thrashing with a big stick, or even better wheres my gun!