My Discovery keeps overheating, What can I do?
#13
That is very intermittent of a problem. I would think there is something in the cooling system getting clogged in the thermostat. Did you ever use a stop leak product or anything in the system? I like to flush the cooling system with a water hose through all of the lines (disconnect the reservoir tank, disconnect the heater core, disconnect the top radiator, everything). Then I take compressed air and force out all of the tap water (making sure not to use high pressure, because you can bust the radiator and the heater core with high air pressure (according to the repair manual)). By this point, the thermostat is off, and I check the side with the little holes in it to see if anything is stuck in any of the holes. Personally, I fill the system with distilled water (tap water can cause the aluminum to corrode) and I test the system with the less expensive distilled water rather then the regular antifreeze that will have to be drained again if it isn't fixed.
#15
hi,
I have a W reg Land Rover Discovery TD5 (Auto) and it keeps overheating on long (ish) journeys. It does roughly 50 miles then overheats and pours water out of the pressure cap, I have changed the pressure cap and the thermostat. I guess the water is circulating properly because i have heat inside the car when the car is revving, but when stationary for a while, it starts to blow through cold. I have also fitted a new power steering pump, but do these cars have problems with the Water Pump? the car can run for hours without the pressure cap on outside. Theres no signs of oil in the water and no smoke coming out of the exhaust. Can you help, or give me advice of what to do next?
Thanks.
I have a W reg Land Rover Discovery TD5 (Auto) and it keeps overheating on long (ish) journeys. It does roughly 50 miles then overheats and pours water out of the pressure cap, I have changed the pressure cap and the thermostat. I guess the water is circulating properly because i have heat inside the car when the car is revving, but when stationary for a while, it starts to blow through cold. I have also fitted a new power steering pump, but do these cars have problems with the Water Pump? the car can run for hours without the pressure cap on outside. Theres no signs of oil in the water and no smoke coming out of the exhaust. Can you help, or give me advice of what to do next?
Thanks.
Yes the motor has a loose sleeve wich creates the heat then it boils
Regards David
PS Over reving next but not related
Regards David
#16
Radiator could also be sludged up, giving less effective square inches, can show up as idles OK, but overheats under load. One test is to warm up truck, switch off, and check fins for temp. If more than 10F cooler at the bottom then sludge may be present. Hard to flush out if Dexcool related. Slipped sleeve may also be happening but would also need a cracked block to allow water to escape, would make gurgle sounds under dash, loss of coolant, and white smoke from exhaust. I hope you just need a radiator and not a block. Half a radiator or 2/3 a radiator is not a going to work in summer.
In the pix you will notice one water pump has brown coating inside, which is from stopz leekz. So it is like pulling on a jogging suit for your run in the desert. Sometimes, that extra insulation is just not needed, the entire inside of the cooling system is coated with it.
50 miles seems like a slow over heat buildup, many with cracked block on V-8 gas have reported temp spike in just a short drive, white smoke, etc.
There are after market water pumps now with larger bronze impeller, for more flow. Old pumps can be worn, leak, wobble (eating metal), and crudded up (use of soemthing other than distilled water).
As a stop gap measure you might try some Water Wetter, which can help hold down temps, won't drop them below themsotat rating.
In the pix you will notice one water pump has brown coating inside, which is from stopz leekz. So it is like pulling on a jogging suit for your run in the desert. Sometimes, that extra insulation is just not needed, the entire inside of the cooling system is coated with it.
50 miles seems like a slow over heat buildup, many with cracked block on V-8 gas have reported temp spike in just a short drive, white smoke, etc.
There are after market water pumps now with larger bronze impeller, for more flow. Old pumps can be worn, leak, wobble (eating metal), and crudded up (use of soemthing other than distilled water).
As a stop gap measure you might try some Water Wetter, which can help hold down temps, won't drop them below themsotat rating.
Last edited by Savannah Buzz; 07-20-2012 at 06:26 AM.
#17
I saw this The overheating Rover engine .
In paragraph 6 he states :6. The cylinder head gasket.
Hey, that's my favorite one. The Rover engine has a special design fault in his heads.
torque sequence
The heads are held on by 14 bolts. The problem lies in the bolts 11-14. When they get tightened they put an load on the upper bolts, raising the heads by a slight amount. New engines are tight but as the engine gets older the heads allow hot gasses to enter the engine,oil and water galleys. This normally occurs only when high pressures= high load is applied on the engine. Those hot gasses do all sort of mess inside:
- They heat up the water. Even a small amount rises coolant temp dramatically. As this occurs only under load it's difficult to diagnose.
- They are responsible for oil leaks. Oil is pressed out by almost any seal as the vents can't take that much. Hard to find.
- They make black sludge as they burn the oil. This sludge prevents the camshaft from being lubricated. Lobes wear off and power drops.
A good indication of this blow-by is that the tin seal plate in the V makes a bulge as it's pushed up by the pressure. You can see this plate from front or rear under the intake manifold.
There are several possibilities to remedy this. You can take out the offending bolts without any drawbacks (that's what I made). The 4.6 engines and heads don't have this row anymore while the rest of the engine is pretty identical. Or you can fit an composite gasket from RPI in place of the standard metal head gasket. This gasket doesn't have the holes for those bolts either. This gaskets seals much better but also drops compression by a small amount.
Look at RPI's page for some good pictures of this.
Could this be the cause?
In paragraph 6 he states :6. The cylinder head gasket.
Hey, that's my favorite one. The Rover engine has a special design fault in his heads.
torque sequence
The heads are held on by 14 bolts. The problem lies in the bolts 11-14. When they get tightened they put an load on the upper bolts, raising the heads by a slight amount. New engines are tight but as the engine gets older the heads allow hot gasses to enter the engine,oil and water galleys. This normally occurs only when high pressures= high load is applied on the engine. Those hot gasses do all sort of mess inside:
- They heat up the water. Even a small amount rises coolant temp dramatically. As this occurs only under load it's difficult to diagnose.
- They are responsible for oil leaks. Oil is pressed out by almost any seal as the vents can't take that much. Hard to find.
- They make black sludge as they burn the oil. This sludge prevents the camshaft from being lubricated. Lobes wear off and power drops.
A good indication of this blow-by is that the tin seal plate in the V makes a bulge as it's pushed up by the pressure. You can see this plate from front or rear under the intake manifold.
There are several possibilities to remedy this. You can take out the offending bolts without any drawbacks (that's what I made). The 4.6 engines and heads don't have this row anymore while the rest of the engine is pretty identical. Or you can fit an composite gasket from RPI in place of the standard metal head gasket. This gasket doesn't have the holes for those bolts either. This gaskets seals much better but also drops compression by a small amount.
Look at RPI's page for some good pictures of this.
Could this be the cause?
#19
#20