RangeRovers.net Forum banner

1 - 7 of 7 Posts

·
Registered
1995-2002 Range Rover P38A
Joined
·
230 Posts
Discussion Starter #1
Been chasing a small, half teaspoon or so at a time, coolant leak from the upper hose fitting on the thermostat where the pipe from the water pump connects.

Only happens as the car cools down after being run. Perhaps an hour or more after stopping but always apparent overnight. Marks its territory in my drive but not at the supermarket. So far as I can see its not loosing water when being run as even quite long journeys don't show a drop in coolant level en route.

I fitted a new set of hoses, said to be good aftermarket, but not factory, after I bought it about 25,000 miles ago back in 2011 and saw it clearly had some sort of sealer jollop in the system. Which I later put down to sealing the almost impossibly inept job a previous mechanic had made of fitting a water pump and gasket. Over the years I've fixed a few other baby leaks where the jollop was wearing out.

After both worm drive (genuine Jubilee) and Mikalor stainless steel band clamps had proven ineffective I did the nuclear option of fitting a new factory hose and new factory thermostat. The hose sat much tighter on the thermostat so I figured I had it fixed. Especially as no drips overnight. Car stood for a day and next morning the drip was back. Done all by itself with a dead cold engine. Currently it has the factory spring type clip fitted. Allegedly these are better at maintaining even pressure all round the joint regardless of temperature changes.

Unless someone has more ideas on where to look for the problem I'm going to have to abandon my principles and put some sealer jollop in. Question is which one. Waterglass has been suggested but I'm hesitant to put that in an engine. I do wonder if the older dose has blocked up a small hole somewhere vital for pressure to equalise during cooldown but I'm darned if I can think of anything. The small pipe from top of the radiator is clear.

Clive
 

·
Registered
Joined
·
965 Posts
Sealer fluid usually does more damage than good in the long run, so I would strongly advise against use of any such fluid in your system. Way back, I've experience of using a variant of sealer fluid in my P38, and the end result was replacement of radiator (Due to blockage) right away and heater core (Due to leak) later on. Sealer fluid may or may not block the leak you're trying to fix, but it almost always blocks passageways that's vital for the vehicle as well.

If you're seeing actual drip of coolant under your vehicle, locating your leak should be fairly easy. Also, if you're seeing coolant puddle near the drain for HVAC, very possible your heater core is leaking.
 

·
Registered
1995-2002 Range Rover P38A
Joined
·
230 Posts
Discussion Starter #4
I can see the leak just fine the morning after parking. Pretty much always a small droplet hanging on to the front of the thermostat right where the end of the hose almost touches the main body. Nothing further up shows wet. UV dye in the system only shows up there too.

Its not the waterpump. When you have an issue with that there is always evidence higher up.

Clive
 

·
Registered
Joined
·
965 Posts
If you're certain that the coolant is only leaking from the host from the thermostat that goes up towards the top of the engine compartment, I wouldn't do too much to it to potentially aggravate the situation. I can't imagine your vehicle losing much coolant from such a small leak, anyways.
 

·
Registered
1995-2002 Range Rover P38A
Joined
·
419 Posts
My old thermostat was cracked at the seam and leaking, but it was very discolored and old.
 

·
Registered
1995-2002 Range Rover P38A
Joined
·
230 Posts
Discussion Starter #7
TheoR

Objectively you are right, coolant loss is minimal and easily replenished during the regular under bonnet checks. But its annoying. My main worry is that this could be a known early indicator for something that should be fixed in due course before it it turns into a real problem.

Far better to schedule an early fix into the service schedule than be forced into doing it, invariably at the most inconvenient time, when it turns into a major issue. 18 year old car after all so its entitled to a few foibles.

xrav22

Thanks for that info. The possibility of a cracked thermostat housing was one reason why I decided to change mine. I don't trust old plastics, especially if they get hot and cold on regular basis.

Clive
 
1 - 7 of 7 Posts
Top