1998 disco overheating

[dgdisco]

My mechanic has changed the thermostat, waterpump, top and bottom radiator hoses, and disco is still overheating after driving about 7 miles. They're telling me it's a weak fan clutch that's causing the problem still. Can a weak fan clutch cause overheating?

 

[joey]

it is possible for the fan clutch to do this, but sadly is sounds like your mechanic has no idea what to do or how to trouble shoot an issue without throwing parts and your money at the issue.

How many miles are on your Disco? Are you using the A/C when this happens? If so, do you hear your A/C fans come on?

 

[dgdisco]

It has 130k. Yes, the A/C is on and yes the fans are coming on. They stay on for a few minutes after the disco's shut off too.

 

[joey]

If it were my guess, I would have your radiator tested... could be clogged.

The clutch fan can cause this, easy test is to spin the fan before you start you rover i.e. when it is cold. Remember how easy or hard it was to spin. Start you rover and let it warm up (not overheat), then check the resistance again after you shut the engine off of course.

http://www.popularmechanics.com/how_to_central/automotive/1772922.html

I will say this though... if you are driving over 25 - 35 mph and it is still overheating the fan isn't doing much anyways... the fans main purpose is stop/idle and heavy stop and go traffic or if you are pulling heavy loads.

 

[wolf]

I would follow Joey's advice and get that rad tested as I just don't think a failing clutch-fan alone would cause the overheating. These engines have huge rads and an enormous amount of coolant for their rather meager 4.00 liter displacement. I have driven all the way down to San Diego through scorching hot July days and not a problem - even though my clutch fan was not working. I believe the clutch fan is just built-in LR redundancy in the heating/cooling department - an area that they are well-known for being top quality in (that's why you see them in so many desert countries).

Wolf

 

[joey]

Personally in the winter I don't even have my clutch fan installed. I only install it once the temps get about 70 degrees or I know I will be driving in stop and go traffic... it did start to overheat on my once this last winter, got almost 8 inches of snow in just a couple hours and got stopped in stop and go for about 40 minutes... seen the temp go up and just put the fan back in.

 

[dgdisco]

Thanks guys. I'm going to address the rad next. I'll keep my fingers crossed.

 

[joey]

Remember have it tested by a radiator shop, not just your local mechanic.

 

[Taytum98]

My 99 disco 1 sd use to try to over heat. Found out the Rad. was clogged, flush the Rad. out refill. and problem was gone. Wish you luck !!!!!!!!!!!!!!!!!