Hello all,

I have a 96’ Discovery that I purchased 6/13 of this year. Ever since I purchased it there has been overheating issues. When it does this the gauge goes from normal up to ½ to ¾ to H and I loose antifreeze. Here is the series of events

1. Overheated on way back from purchase bout 1.5 hrs away
2. Flushed and new coolant
3. Drove 4 hrs from CT to VT no problems
4. Overheated in VT
5. Brought to a VT shop and had a new thermostat put in, obviously the previous owner had it taken out since there was no thermostat.
6. Overheated many times on the way back, kept having to add antifreeze and water and make frequent stops.
7. Brought to local garage, they put in another thermostat and test drove. They said that it didn’t overheat for them and that it seemed fine.
8. Drove it to work and around town with AC on and it did fine for a couple weeks since its my only vehicle. However one time I noticed a small coolant leak on the left side after driving for about 25 minutes the area has not leaked since.
9. I brought it to another garage they pressure tested it, looked it over and let it run for 2 hours and it didn’t overheat. They couldn’t find the coolant leak that I had noticed before. I drove it today without the AC and it overheated. The gauge was normal for a while 30 min but then went up to ½ then to ¾ and a little more, then going down some hills it returned to normal.

I am completely stumped, the water pump looks new and it’s obviously not the thermostat or the auxiliary fans. What does this sound like to everyone? I will try to provide any more information that would be needed. Thanks, Tom

 

Tom,
Did anything come out when you flushed it ? The first thing I would think of would be a clogged radiator. It could be that the previous owner put a bunch of stop-leak or something in it and it's clogged up the rad. If this were the case, then usually moving won't help the temp go down - I mean it could overheat going 50 mph. A radiator shop might be able to verify this without pulling the rad.

 

I had this phantom over heating problem before. Although it wasnt with the Disco. It turned out being a warped head. It didnt show up in a pressure test, I replaced the thermostat and heater core as well still no improvement. Check for any leaking of coolant or oil from the head. Also have you been bleeding the coolant system everytime you opened up the coolant system? If not an excess of air could be in there, which could explain it sometimes overheating and other times being fine. When excess air expands and takes the room of the coolant in the system when the engine temp rises(Charles Law).
Also check the fins on the radiator or any debris. Are you using the pink coolant?

 

DiscoJag, to answer your question, no, nothing really came out when I flushed it. Yes the first shop I brought it to said that it looked as if someone had used stop-leak in it, maybe this is the problem!?

BMF175, I really hope it isn’t a warped head. I will look again for any leaking around the head when it gets hot but I don’t think there is. It is possible that air is in the system, I will have to check into this. No, I am using the green type coolant.

Any and all other comments and suggestions welcomed. Thanks, Tom

 

Two quick cgeap test will confirm what is wrong.
Have a shop do a pressure test on the coolant system, if the pressure drops and you see no leaks, it will be an internal leak. The other test would be to do a chemical test of the coolant bottle checking for exhaust in the coolant.
One way or the other it will show up. Whatever you do, stop letting it get warm, you are killing your heads.
Mike

 

Also there doesnt need to be an external leak of fluids to be a warped head. In a warped head sometimes it wil just bring air into the system to compromise it. Not saying it is a warped head but it is something to check, like I said the excat same symptoms could mean acouple different things.
You mentioned that you have brought it to your local garage, have you had the chance to take it into a LR mechanic?

 

Thanks guys. I try to be careful and don’t let it get too warm now; I know I really don’t to cause any more serious damage. No I can’t find a LR mechanic, can you recommend any in CT? Tom

 

Tom,
You didn't get what I was trying to tell you, don't drive it except to a shop, even if it is just a good radiator shop.
At $1000 a head plus labor, you can't afford to tempt fate.
To get it checked, any good shop can do it, it doesn't need to be a Rover shop, just make sure they can do both tests.
Mike

 

It sounds like you might need a new rad. A rad. shop can do a flow test on your rad, but it will have to be removed for that. The coolent may not be moving through the rad. the way it should. You may be able to get it recored. If I was you I would take Mikes advice and do not drive it until it is fixed.
irishrover.

 

I had/have a similar problem with my '98. It was overheating a few weeks ago and when it did, it would leak from the upper drivers side corner of the rad. I replaced the termostat and it hasn't overheated since, but Tuesday and today it has leaked a bit of coolant when I stop the vehicle. The temp gauge doesn't show it getting too hot (it stays right where it always has, near the bottom of the normal range).

I am going to take it into a local rover shop and have them look at things to see if they can figgure out what is wrong.