Purchased my 1995 Discovery (british Green!!) in May. I always have been a Benz guy but longed for a Land Rover and always loved the discos inside and out. I have never been handy but have always used this forumn to diagnose and reccomend to mechanics what to do., I have fixed fuel lines, etc for cheap!

I moved to Texas from New Jersey and last week a mechanic put free on in the car as the ac was blowing but not cooling. After adding the A/c the car became cool but I noticed on my drive home the temperature gauge rise to hot as I drove about 5 miles home. I checked the coolant level and it seemed a little low. So I added coolant (dexcool 50/50)

The next day We drove it and after about 5 miles to work it started to overheat. When I parked car I heard an intense boiling under the hood, engine and everything udner hood was extremely hot. Fans seem to kick on but not sure if they are always kicking on.

I have not seemed to lose any more coolant.
temperatures this last few weeks have been 100+ with heat indexes of 110+ . Many cars are overheating and car rental places are sold out.

What do you guys think. I need cheap 1st before expensive. any help would be great!
Coolant flush?
Radiator Hoses clogged?
Dredded head gasket?
New Radiator? New hoses,
new temp gauge?

I really cannot spend too much on it now and this will determine the future of m y relationship with this Rover.

Also any good shops in the Houston Area with reasonably priced diagnostics.
Thanks again
Mike

 

Mike, start with the basics but when you say dexcool, do you lean the orange? If it is and hasent been properly flushed prior get it out. It's not made for our cars. Does it overheat with the ac off? Start with the rad flush, how miles on it? May need rodded. Change your tstat. Check for correct belt routing, are you weaping any coolant? May be time for a new water pump. At the same time you may want to change upper and lower hoses if not already done.

 

Dexcool is blue I beleive that I used. It does overheat with the ac off.
The Disco has 118k Miles on it.
I noticed in another post about the resevoir.
My expansion tank/ resoivor during boiling shows now signs of actual leak but is the original black and and when boiling you can see the boil trying to burst out of the top of the tank.. almost visibly you can see the bursting. Coolant could possibly be breathing its way out to cause imbalance in pressure??

SO this may be my short plan.
1. Radiator Flush
2. Change the tstat (Can I purchase the part online anywhere?)
3. What is belt routing? Is this breakage or cracks in belt?
4. Do I rodd it if Radiator flush and tstat does not work?
5. Also change upper and lower hoses, should I also change resevoir tank
6. What is the cost of a new water pump ( Can I purchase online?)
7. Should I use a land rover specialty show for this work or can any decent mechanic do the work with my specifications.

Thanks Again, response really brought some clarity and direction to my worry and frustration.

Mike

 

This is a more serious issue than you might imagine from owning a Benz. My W124 cruises along at 80 c, with a little blip of 2 - 5 degrees idling in traffic. Might touch 100 C if low on coolant, but never had it above that, which is midpoint on my guage.

Now for the Rover - all aluminum engine, overheat very very bad.

Normal temp range is 1/3 on the guage to 1/2. Easy to check with an IR thermometer. ABove 1/2 is time to be doing something about it promptly.

Here is a list of possibles, not in order:

Fan belt route wrong - check the RAVE manual or recent posts.



Radiator clogged or restricted - older unit, but built of brass and copper, can be acid flushed and rodded out by a small indy radiator shop for about $65 - look for a shop that does tractors and heavy equipment, they don't care about the Disco MSRP, and make their boat payments off the big iron. Tubes run horizontal, so radiator can be hot at the top and colder at the bottom, water is only flowing through 50% or less of the radiator. Good radiatior is around 10 degrees across the face of it. Flush it yourself may only give tiny bit of relief. Comes out of the truck easy, four rubber hose connections, two sets of metal lines on left and right. Battery side is oil cooler lines, driver side is tranny (plus another cooler in front of it).

Radiator and condenser (AC radiator) can be full of mud from too much time in the woods. Check with flash light, hose out, but don't use pressure washer which will tear up fins. Radiators can be hundreds of dollars.

Thermostat - under $20, change it out, be sure coil goes into block, be careful it does not slip down when installing gasket and leave a big gap. Don't put in a 160 F, the tranny won't go into overdrive below 150, and there are other mpg issues. Backwards mounted stat will cause overheat.

Radiator fan - cupped side of blades toward radiator. When cold, fan should turn stiffly on the viscous clutch. When warm, it should turn easier, but anything over 1 revolution is suspect. Free wheeling means it has lost the internal fluid. In the tech section there is a good write up on using a $49 Chevy model, works great. If you are overheating at 40 mph, it is not the fan or clutch.

Space between radiator and condenser - great place for trash to collect and block radiator - free to fix, just remove rubber strip.

Front electric fans - come on when AC is on, when temp is 212 in engine, and when engine temp and fuel temp are above a threshold and truck is off. Fans should blow toward engine, test with wimpy plastic bag, Ac and fan on, engine off. Bag should pull toward grille. Note - a normal radiator fan will "roar" at cold startup, moving more air as it reaches operating temperature. Mine will spin the electric fans, even when they are not turned on. The roar lasts just for a minute or two. Electric fans just cool AC compressor during slow moving periods or idle.

Water pump can be part of the problem, but should have been acting up before "heat wave." Less than $200.

Head gaskets - usually make bubbles in coolant, which is heard as sloshing sound inside dash near heater core, and/or white smoke from exhaust. Big $. $500 for DIY, $1500 up for shop. There is a chemical test you can buy from auto parts store to test for this.

 

Anyone taking bets on how many more of these overheating during high ambient temperature threads we'll see before summer ends?

 

The Dexcool was blue? What? Did you put windshield washer fluid in there?

 

Don't believe I have ever heard of blue dexcool. Might double check that first to make sure you added coolant.

 

Belt route is found in RAVE workshop manual, section 12 V8i engine, "Drive Belt Renew". If not available, here is how to do it for one WITH air conditioning.

Start clockwise at top of alternator. Belt goes from over top of alternator to under the fan pulley. From under the fan pulley to over the power steering pump pulley. Around the PS pump pulley, and down and under the crankshaft pulley. Up and over the idler pulley on the tensioner. Under the air conditioner pulley, around it and back to the top of alternator.

Nothing special about the thermostats, available at most parts shops. If you pull radiator and fan, you are looking at less than an hour to do the water pump. But water pump can be pricey. You can inspect it internally for the cost of a gasket. I was in a hurry, grabbed one off a Disco 2 (same pump) for $6 at salvage yard, not always the best choice, but in a pinch for diagnosis, not bad.

 

Dex-Cool ain't blue bro, its orange.

 

Savannah! thanks for the input, I will do do as much DIY as I can and keep you posted of my progress.
I will double check the dexcool color then. I was going off of memory and need to look at the color. I have it in my rover at home.

Thanks for all the responses