Cooling System...

[pvt.tadpolxj]

Hey Folk's....My XJ is having a little overheating drama...And has been doing this for about a year...I really do know how to make it better, but I keep wondering about using the Grand Cherokee Clutch fan..Or is it only the Clutch part that some of you people have ben converting to. Would somebody out there let me in on this change over and what benefits will it give on my 1991 XJ. :stars:

[Mudderoy]

Hey Folk's....My XJ is having a little overheating drama...And has been doing this for about a year...I really do know how to make it better, but I keep wondering about using the Grand Cherokee Clutch fan..Or is it only the Clutch part that some of you people have ben converting to. Would somebody out there let me in on this change over and what benefits will it give on my 1991 XJ. :stars:

The Grand Cherokee heavy duty fan just means it will move more air sooner. It is really only a low speed fix. Some people have been having problems with clearance. This can be especially bad if you have bad engine mounts, or transmission mount.

If it's over heating you may have other problems that a heavy duty fan clutch may help to mask.

[dagr8tim]

First step would be a good flush of the system IMHO. Fan upgrades and such are just band aid fixes.

Find the root problem and fix it. Then do fan upgrades. You can never have too much cooling for an engine.

[Carves]

First step would be a good flush of the system IMHO. Fan upgrades and such are just band aid fixes.

Find the root problem and fix it. Then do fan upgrades. You can never have too much cooling for an engine.

X 2 ...

Most issues are just a result of a neglected and wornout part - not being able to do its job properly.

The 4.0l XJ started life with an underperforming - or if you prefer ... barely adequate, cooling system ... and needs to be in good nick always.

Doesnt hurt to improve on a coupla stock items tho ...

Radiator & fan are certainly worth stepping up a notch ... since they are the items that provide the cooling.

Whether or not a GC fanclutch is of benefit to you - depends on your driving requirements.

I'm only using a USMW one (derale apparrently) sold through rugged ridge ... Its not as heavy duty as the GC ones ... but certainly better than any new "chrysler" one Ive used.

Theres a writeup on the U.S., Hayden website that explains the differences between an ordinary thermal fan clutch & a heavy duty one.

They all should activate at about the same temp ... roadspeed regardless ... but they when activate ... they spin at different percentages of the engine revs.

The old style non-thermal type operation is also explained.

Interestingly ... the fan blade pitch info, on the Hayden site - also suggests that the XJs fan could do with a few extra degrees too .... when you compare the XJ FSM specs. ....

Not something Ive tried but one fella down here mentioned he has .... and believes there was an improvement.

All good fun messing with cooling systems. :D

[JMadigan]

I had an overheating problem a year or so ago; If you've never changed or flushed the radiator it can get clogged up on the inside because of something to do with the thin ribs of the radiator. Once I replaced the radiator the temperature dropped to normal and now it works great! hope this helps!

[pvt.tadpolxj]

Thank's.......:pray: