Hello out there:
I'm brand new to the forum and Land Rovers. My neighbor is giving me their 1995 Disco, first sold in California 01/09/1995. A LR mechanic in the neighborhood has rodded out the radiator , changed the thermostat and put in a new fan viscous clutch, he said the water pump was OK, and the water hose inserts are intact. He says that he found a white film on the parts he replaced (stop leak?) and the indications don't point to a blown head gasket. The engine begins over heating after driving it about 45 minutes. He feels that it might be clogged water jackets. I'm planning on doing compression tests to confirm the no blown head gasket theory. If the pressures are good I'll pull the heads and look around.
Any suggestions for possible problems?
Would a plugged heater core cause this problem since I understand that the water flows through the core all the time??
The disco sat for about a year but I recharged the battery and the engine started right up and purred like a kitten, sans water. Only ran it about 20 seconds. Thanks for the help!!!

 

Plugged heater core won't cause overheat, and on the 95 I believe you still have a on/off heater hose valve.

Most mechanics in the neighborhood would not have equipment to unsolder the side tank of a radiator and rod it out. That sort of thing is usually in a radiator shop.

Let's go down a check list and see if things are working.

1. Coolant at reference point in reserve container and not dropping when check day to day.

2. Coolant cap should be renewed to hold pressure and keep coolant from being lost while driving.

3. Radiator, if not clogged, should show a spread of temps from top to bottom on the fins in a vertical line of no more than 10F. Greater difference indicates lower rows are cooler because of clogs.

4. Viscous fan, when hot, truck off, spin, release, it should stop in less than 1 revolution.

5. I would have put in a new 180F thermostat.

6. New fan clutch and old water pump - that is like having a 70 year old man start dancing with a well oiled Brazillian beach babe body builder. The old clutch was weak and did not put full load on fan or pump. New WP may be in the future.

7. Fan belt route?

8. Water jackets have some smaller spaces, but there are also cracked blocks, etc.

 

Thanks Savannah Buzz.
I think the mechanic had a radiator shop rod out the radiator. I for one think a new, high quality water pump should have been installed too. Is there a high volume water pump available from the aftermarket? I'm just starting to get into this project as time allows. First up is pressure testing the cylinders, then hooking up the coolant hoses and pressure testing that system. I'll keep you informed if you would like me to.

 

BP Utah and some others sell this sort of WP, which has a bronze impeller and moves more water. But overheating after a period of time makes me think of radiator not 100%, might want to check that out as well. Is the overheat at freeway speed or just in traffic around town?

Older water pumps wobble, leak out the front, and are generally scaled up inside.

Pix of where to put the 180F thermostat ($10 ish), spring goes inside the block.

 

The pervious owner does a lot of running around town with the kids and drives the freeway to work. I'll get a better idea from her about the overheating. The radiator is original and rodded out but the core is not as wide as the end tanks. There is about 5 feeder slots available but sealed off. Should I have a wider core installed? I bought an OTC compression testing kit and I will try to get some pressures this week. What are your thoughts about Evans waterless coolant? Is a 160 degree thermostat too cold? I prefer the bronze impeller water pump too. I'll buy one and install it before I reintroduce coolant to the system. I'm hoping that it's just a cooling system that was plugged up, and I'll have to check the electric fans to see if they are working properly too.

 

Forget the waterless coolant, it is for museum cars and specialty vehicles.

160 is too cold, you will never have enough heat.

You can spend a fortune on a new copper radiator or having one recored, there is an aluminum aftremarket one for $235 ish.

Electric fans should come one when AC switched on. Paper towel should be held against grille, not blown away.

 

So you are saying that it would be best to replace the radiator with one with a thicker core?
What's the best source for the aluminum radiator?

 

The original radiator is a copper and brass model, with three rows. $800 plus if you can find one. $450 ish to have recored.

An aluminum replacement has popped up on fleaBay, some members have installed it. While it won't last as long as the oem style, it is better than a radiator full of sludge.

Note that radiator has tranny cooler on one side and oil cooler on the other.

 

Savannah Buzz:
The radiator has been rodded out by a radiator shop so hopefully it's flowing good. I forgot to mention that the previous owners have a very tired serpentine belt and they don't have a fan shroud on the Disco. Runs at least 15 degrees hotter because of that??
I did compression test today:
#1= 175, 3=175, 5=165, 7= 175, 2= 175, 4= 165, 6= 180, 8= 170.
The tests were run on a cold engine, dry cylinders and the pressures held for a long time.

 

Compression isn't too bad, should be around 10% - 15% between highest and lowest, which you are.
Odds are really good you have the wrong thermostat if it was purchased at a local parts store because all the books list a 195 and it seems a lot of people don't really understand what the temp number means anyway. But call them, and ask innocently, "What temp thermostat did you install?". If a 195, replace it ASAP. This is the one I use: https://landroverforums.com/forum/di...rmostat-51327/

As for the electric fans, they should really never come on when driving unless the AC is on. IF they are, then you are definitely running too hot.