Need info help - overheating

[RROVERHSE96]

G'day all i have just joined and hoping that someone can help me with a problem.
I have a 96 Ranger Rover HSE 4.6 and i have a couple of problems the first is that it is over heating, or should I say that it gets very hot without actually over heating, the light comes on and then goes off after maybe 30 seconds to a minute and the temperature goes back down once I back off it slightly.
This is my first Range Rover and I'm unsure if this is a common problem, it has so far done it when idling in traffic for long periods and when towing a horse float at 100km on the freeway, both on hot days.
I'm not sure if this is cause for concern, I have considered things such as upgrading the original radiator, I don't know if it's the thermostat or both, but I don't know if there is a more simple fix.
So just wondering if anyone has some insight/hints/tips as to what this can be and what I can try, we purchased the vehicle primarily to tow a horse float, mostly long distances so this is something I need sorted out.
Any help greatly appreciated.

[slick]

hi i had the radiator rebuilt in my 93 disco that had similar heat issuses when towing radiator specalist told me it was full of gunck no surprise it was 18 years old kept it the same as it must of worked when new now always runs just below half temp on gauge towing or not hope that helps

[Grumbles]

I'd suggest an immediate radiator removal and rodding along with getting the viscous cooling fan hub reco'd or replaced. Maybe even the water pump too.

Being a 1996 model it has had 16 years to wear items out and to sludge up.

The biggest killer of these engines is over heating which warps the heads and requires a top end refurb. If you are really unlucky with an overheated P38 engine then you might get cylinder liner movement as well which is basically new engine time.

Let's hope that you catch it in time before serious damage is done.

In a good condition cooling sustem the temperature gauge needle should always be at a constant point and not move no matter how hot it gets.

[DT-P38]

What Grumbles said...

Also, powerflush the cooling system and replace coolant too. A lot of people around here recommend the red coolant (also spec'd for chev alloy LS1, etc series V8's). Doesn't hurt to check your expension tank hose isn't clogged and that the tank actually gets refilled when the engine cools. Expansion tank caps have also been known to fail.

Welcome aboard AULRO, hope you can save yourself some grief (and $'s) by using the wisdom many have contributed here. Where in Vic are you? There are many LR repairers around, if you dson't have a good one then people here can provide some guidance... e.g. if East of Melbourne I usually refer folk to AMV in Ringwood.

Dave

P.S. Try using the search function in this section and read everything that pop's up with the words "over heating". Don't know whether it helps, but you are not alone, nor are you the first or last to have this issue.

[adm333]

YES

This is cause for concern. Particularly if you depend on the vehicle to transport horses, you don't want to get stuck somewhere with them on board !!

Your cooling system is under par, which means you are in a high risk category for major problems.

Are you aware of any coolant loss at all? check it every day to see if it is losing coolant. Have a good look under the car for signs of leaks, down the side and back of the engine and near the water pump. I flatten out a cardboard box and put it on the garage floor, you will soon see what's leaking from the car, don't panic about the aircon condensation.

Also, I would not recommend trying to clean your old radiator, just buy a new one. These radiators have plastic components that are fragile and brittle. Get a higher spec one if budget allows but oem should do the job.

Check and replace hoses as necessary and get a new pressure cap, as mentioned.

It's also worth checking that the twin cooling fans in front of the radiator are working, these are integrated with the air conditioning to come on and provide extra cooling in extreme temps.

Just a few ideas

Dave

[wayneg]

If you are reasonably handy its easy to take the rad out so you can get it flow tested. As already stated if its restricted taking the tanks off will most probably break them, I know the hard way. Test the fan viscous coupling to see its ok. You can buy a new Rad for $368 shipped on e-bay at the moment. I had several small heater hoses burst then overheating under high stress before I changed the Rad, it was almost totaly blocked. All good for 2 1/2 years now. I have just changed the water pump as that was found to be on its last legs at 227k and fitted a low coolant alarm for piece of mind.
Dont leave it or you will no doubt be sorry.

[98se40]

Hi and welcome,
I fitted a " engine saver " advertised here on site. Cut it into the top rad hose. Wired it back to a spare port on the console. So if ever there is no water in the top hose, audible and visual are heard and seen.
Of course do this after your problems are fixed.
I know this as I have just had the whole 4.0 pov pack completely rebuilt due to overheating damage

Cheers

[PaulP38a]

Hi and welcome,
I fitted a " engine saver " advertised here on site. Cut it into the top rad hose. Wired it back to a spare port on the console. So if ever there is no water in the top hose, audible and visual are heard and seen.


Which kit did you buy from their site? Any problems with install or false alarms?

Cheers, Paul.

[98se40]

Hi Paul,

Im not sure of the part number, but the guys name is Dave, lives in Brissy I think. ( tel 07 47766334 )Just told him I had a p38 4.0 ltr. He told me mainly that to check what type of diameter the top rad pipe was. Then he advised which one would be suitable.
Had a false alarm as soon as I wired it up. Rang the guy ( Sat arvo 5.00pm ) and he gives advice at all reasonable hours. Knew what the problem was ( I had an air bubble ) so to rotate the sensor to the bottom of the pipe. Did that, no false alarms. After having it for more than 6 months now, and have been able to rotate it back to the top with no false alarms. ( air bubble bled and gone ) Testing is easy. Just unplug and the audible/visual will show on dash. Even tested by taking off the top rad hose again, works a treat. Cost $160 delivered I think.
Ran it down the door frame and through into the body, under the dash and onto the console. Its a small cable so rather easy.

Hope I never have to use it, but peace of mind knowing that if there is no water in the top hose, then Im told that this alarm should stop any major damage that could happen if continued driving occured and waiting until the temp gauge goes ballistic. By then its too late, as I have been a victim of : (

Hope this helps
Steve