My 97 Disco began having overheating issue's a few weeks ago. It would begin to get hot until I pulled over and turned the truck off and once i restarted it, the issue would go away.

I went and replaced the thermostat and bled the system but now its happening all over again. When i pulled over today to check the radiator, the lower part of the radiator was cool and the top is warm. Could the radiator be clogged and need to be flushed or could it be something else?

Its still the original radiator with 160K miles on it. If anyone has any ideas or knows of a good shop open on Sun near Trenton, NJ please let me know as im worried it wont make it back to NYC. Thanks

 

sounds like the radiator has **** the bed. not sure who is open but here is what a quick google brought up. also check out our local forums NJLR and NELRC. good to know fellow rover peeps in your area! do you have AAA?

1788 Calhoun Street
Trenton
(609) 394-3722
A-Z Auto Radiator & Air Conditioning


105 Patterson Avenue
Trenton
(609) 586-6222
First Class Auto Salvage
Used Car Parts Trenton, Central NJ - 1st Class Auto Salvage

301 Edinburg Road
Mercerville
(609) 890-0092
J & B Automotive
J & B Automotive - Complete Auto Care - Mercerville, NJ

555 North Olden Avenue
Trenton
(732) 938-4900
1-800-Radiator Trenton

21 Woodside Road
Robbinsville
(609) 223-2722
B&W Auto Body Repair
bwautobodyrepair.weebly.com/

1127 U.S. 130
Robbinsville
(609) 259-9733
Finger's Radiator Warehouse

 

Yes, that was my worry as well. When I drive below 50mph, it doesnt overheat so maybe ill just take hwy 1 backto the city and get it replaced there. Thanks Ed

 

the problem is that temp sensor in the dash doesnt move quick enough. by the time that thing reads hot it's far too hot already. you made sure the fans are working properly?

 

See gauge pix. You are headed for the Colonel - for extra crispy... Certainly check fans, be sure no mud or leaves between rad and condenser, check fan clutch for "freewheeling" when spun after engine shut off and warmed up. A plug in scanner can show you what is happening, before the worthless gauge does. If rad is sludged up, it can be flushed (hot citric acid) and rodded out by a shop. Fins top to bottom show show minimal difference, like 10F. Cold on bottom is no water flow there. We have also had posts about a $235 aluminum eBay radiator that some have used.

 

That picture of the temp gauge and scanner should be blown up and made it's own sticky.

 

Same for D2.

 

Ive checked the fans, sludge, etc and everything isworking properly. I never let it get to red and it doesnt run hot 24/7, only begins to move up towards red then i pull over, turn the engine off and its good again.

 

I was never a very good instructor. The point I am trying to make is that by the time the gauge moves above the 50% area you are already runing too hot. "Normal" temps would be 180 - 195F on the road, depending on of you have a 180 or a 192 F stat at 50 mph. 212 is where Rover has the extra electic cooling fans switch on. You are most likely beyond that temp. The reason is not known at this point.

What many will agree with is that:

1. It will not repair itself.

2. Continued use at elevated high temperature (no matter what the gauge says) will cause significant problems, including head gasket failure, slipped sleeve, cracked block.

3. When you have this "climbing up" before you pull over; what speed are you travelling? If under 30, fan clutch could be an issue. If 50 - 60 mph, fan clutch is such a small part of the equation it can actually be removed. If blades of any fans are turning backwards (mounted wrong, wired wrong) they can subtract from air flow. More likely noticed at slow speed or idle.

4. You changed the stat. Here is where it went. The two sensors on the left are gauge and ECU, a skinned and grounded wire can make wierd readings. The "spring" end goes in the block so water can touch it. Some people manage to get them in backwards. The small hole or jiggle device goes at 12:00 position, so bubbles in coolant can't form a steam pocket and delay opening of thermostat. Your stat could be sticking, some gasket sealer on the moving parts, etc. The normal operation of a stat from cold start, when viewed with a scannner, it to reach minimum opening temperature and go beyond that (overshoot) then cool back down as the stat finally opens. It isn't digital, so it varys a little. Stats can be removed and boiled on the stove to check for operation. If a steam pocket is forming, what is making the steam?

5. If not having coolant loss that is a good thing. If not hearing bubbles under dash (water rushing thru pipes) that is a good thing. An exhaust gas in coolant test will "sniff" the hot coolant bubbles and change color. Can be head gaskets or cracked block. A block crack might have to get to a specific temperature to start to open up, so changing to a 180F stat might in a few cases help. A bad coolant cap can vent coolant while driving externally, not holding pressure, and allowing overheat. Coolant cap has to be good with or without antifreeze.

6. A partially blocked radiator is always a problem. Imagine that you took the radiator from a much smaller vehicle and swapped it. The engine just makes too much heat for the rad to dispose of. So if full on the inside with calcium and scale and Dexcool "mud" the rad just can't keep up. This shows up as much cooler on bottom rows than the top. This is a horizontal row radiator. A small indy rad shop near me will boil them out with citric acid, plus unsolder a tank and rod out the calcium; for about $75 carry in. There have been posts on here about a $235 alumnium radiator for D1's; the copper brass one is maybe $600 plus if you can find one. I would suppose if you drive for 30 minutes before the heating begins, you could try blocking 25% of the radiator with cardboard, and see if the problem happens that much faster. Or read fins with an IR thermometer. I was able to open the rad plug on top, and see calcium coming out tubes with a flashlight. Can't see to the bottom, maybe a pal has a "snake camera".

 

I am hearing bubbles under the dash so ill try to blead it before driving back to NY. The problem is that im 65 miles from my house and so i need to be able to get it home to asses the problem.

The nipple on the thermostat is at 12 so im hoping its just the rad. After owning the truck for 10 years, shes beginning to show signs of age and i just dont want her to nickle and dime me to death