Which pipe? Hoses don’t collapse. If anything their pressurised with air
SpagettiDefender
Member
Yes, this or just remove the thermostat and see if the engine heats up still.
You can also bleed the coolant lines at the thermostat housing.
Do you mean bleed by loosening the clamps on pipe or by loosening the cap. I’ve tried bleeding through the cap
SpagettiDefender
Member
I meant the cap.
definitely check any heater matrixes
Because that is where there are often airlocks that peeps don't see or think about.
If its an airlock in the heater it should not stop circulation to the main engine rad. Does it? I dont know the 300tdi.
J
I have a 300tdi but have never had an airlock or voer heating, but it is always worth disconnecting the heater matrix at one end or the other and then checking it fills properly before reconnecting.
I don't know how important the cooling from the heater matrix is to the whole system, but it must have a bit of an effect at least. There is as far as I know no old fashioned tap to turn it on or off. If you can "short circuit" it and there is still sufficient coolant flow and cooling effect, then it'll make no difference. But checking it can't hurt.
The main rad don't get hot allover
.Airlocks are always an issue but OP has seemed to have got that.
J
Think maybe he needs either a better flush of the rad or a new one.The main rad don't get hot allover
Airlocks are always an issue but OP has seemed to have got that.
J
Hope he did reverse flush it. number of times I've fixed overheating on older cars just by doing that. Wonder if he had done a long journey or two before this happened as in my experience this is what dislodges the carp from elsewhere in the system and flushes it into the rad where it sticks and blocks passages.
I did a long journey the day before with heating on a lot. I did reverse flush
SpagettiDefender
Member
OP did say that the cab heater will blow warm air momentarily but then it's cold - symptoms of a blockage or air lock.The main rad don't get hot allover
Airlocks are always an issue but OP has seemed to have got that.
J
Could it be the impeller on the water pump has come off and is sitting in the housing? This would be a minor blockage and would reduce flow
As there are so many waterways in a rad, it may appear to be succesful as water flows out of the other end, but it could just be flowing through the unblocked tubes.
I know it is a pain to get to and he'll need another P gasket but maybe worth checking. But I hope he can find a really good flushing agent take the rad out and leave the flush stuff in it overnight with the rad full, then try flushing again. doing it on the car can work but I have done that to no avail until I took it off, flushed it turning it in all directions and banging it gently until all the crud has come out.
In both cases it was a case of it having happened after a long journey. In one case from Scotland to Lille in a Morris 1000 van!
And no neither vehicle was mine!
@timbr00 I had this a few month's ago and I'll share what i found out from cooalant leaks on this engine. Have a read and PM me if you want to talk though it. A few of the guys helped me earlier on my Swivel Joints and just paying it forward
While mine is a Disco 300tdi its very simialr. Get some UV leak dye! Your save hours and ton's of money!
When bleeding top up with engine running and burp the pipes, i had problems with this as first. There are some devices on amazon for coolant connectors they look like they could help. I just poured into the thermostat with the bolt out and let the engine run.
If your still over heating themostat out and flush it though with heater matrix bypassed read below and your see what i did. Back flush that seperatly.
Reading through the thread i see no mention of Checking the sensor as that feeds the temp guauge? I'm not aware but could this be faling? At 3 quid its worth replacing. Linked it below:
Sensor
See you mention you replaced the alternator or moved it?
Mine had a leak from a pipe that damaged the alternator, replaced all the pipes just to be on the safe side bar one!. I had someone replace my alternator then it still leaked. Garage suspected the P Gasket. New water pump etc. Still a leak!
It all had to come out again because the Water pump housing had a crack. Worth a check as it appears it was there all the time just too small to be noticed without the UV Dye.
LAND ROVER 300tdi Water Pump Housing ERR3736
The reason all that was caused was overzealous tighneting of bolts to fit the alternator caused it to crack and leak it looks like the P gasket but the casing has split just above the p gasket. We deduced coolant in the bolt hole and excesive force on the bolt caused this whole mess!
Another Leak could be your coolant bottle or pipes, Pressure test them with engine running and without. Worth checking if any of the pipes are soft? Talc is good idea here if you dont have UV dye as you can't always see coolant but when talc gets wet its like a paste but be careful. UV dye is better
The Coolant bottles get old and crack and cap's get old they can leak. I've heard the plastic rad bolts leak slighlty. I upgraded to copper just to be sure.
I had little heat and was loosing coolant slowly my heater was partially blocked unknown to me at the time. It was also leaking on the Heather matrix pipe. I kept loosing coolant and thought i was going mad as i had just gone though all the above before. Check for wet carpets. I thought it was coming in from the windscreen at first.
If they are Bypass the HM and see if your loosing it still. I used a pipe joiner from halfords with 2 jublie clips to join the two pipes. You might be picking up rubbish from the matrix causing a blockage.
I had the heater matrix replaced at another garage and then it blocked the system and the temp went sky high. Crud in the coolant! Who would have thought i asked the garage to do it when doing water pump earlier.
I ended up doing the job myself and flushing the whole system, have linked the one below for you that i used. It really worked well I had to run the hose and flush it 3-4 times but it's really cleaned out the rubbish. Took an hour of running the engine and then running hose though it.
Engine no longer overheats and with HM bypassed no leaks from main system but it was a mission to get there.
Final thought waiting on clips for HM and O ring to fix the final leak and then i should be good for another few years. I just hope no one goes though what i did but sharing to avoid someone else going mad like i did with mine. Seem's the clips on the HM and o rings fail so its worth checking just to be sure.
Hope this helps.
Ben
While mine is a Disco 300tdi its very simialr. Get some UV leak dye! Your save hours and ton's of money!
When bleeding top up with engine running and burp the pipes, i had problems with this as first. There are some devices on amazon for coolant connectors they look like they could help. I just poured into the thermostat with the bolt out and let the engine run.
If your still over heating themostat out and flush it though with heater matrix bypassed read below and your see what i did. Back flush that seperatly.
Reading through the thread i see no mention of Checking the sensor as that feeds the temp guauge? I'm not aware but could this be faling? At 3 quid its worth replacing. Linked it below:
Sensor
See you mention you replaced the alternator or moved it?
Mine had a leak from a pipe that damaged the alternator, replaced all the pipes just to be on the safe side bar one!. I had someone replace my alternator then it still leaked. Garage suspected the P Gasket. New water pump etc. Still a leak!
It all had to come out again because the Water pump housing had a crack. Worth a check as it appears it was there all the time just too small to be noticed without the UV Dye.
LAND ROVER 300tdi Water Pump Housing ERR3736
The reason all that was caused was overzealous tighneting of bolts to fit the alternator caused it to crack and leak it looks like the P gasket but the casing has split just above the p gasket. We deduced coolant in the bolt hole and excesive force on the bolt caused this whole mess!
Another Leak could be your coolant bottle or pipes, Pressure test them with engine running and without. Worth checking if any of the pipes are soft? Talc is good idea here if you dont have UV dye
as you can't always see coolant but when talc gets wet its like a paste but be careful. UV dye is better The Coolant bottles get old and crack and cap's get old they can leak. I've heard the plastic rad bolts leak slighlty. I upgraded to copper just to be sure.
I had little heat and was loosing coolant slowly my heater was partially blocked unknown to me at the time. It was also leaking on the Heather matrix pipe. I kept loosing coolant and thought i was going mad as i had just gone though all the above before. Check for wet carpets. I thought it was coming in from the windscreen at first.
If they are Bypass the HM and see if your loosing it still. I used a pipe joiner from halfords with 2 jublie clips to join the two pipes. You might be picking up rubbish from the matrix causing a blockage.
I had the heater matrix replaced at another garage and then it blocked the system and the temp went sky high. Crud in the coolant! Who would have thought i asked the garage to do it when doing water pump earlier.
I ended up doing the job myself and flushing the whole system, have linked the one below for you that i used. It really worked well I had to run the hose and flush it 3-4 times but it's really cleaned out the rubbish. Took an hour of running the engine and then running hose though it.
Flush
Engine no longer overheats and with HM bypassed no leaks from main system but it was a mission to get there.
Final thought waiting on clips for HM and O ring to fix the final leak and then i should be good for another few years. I just hope no one goes though what i did but sharing to avoid someone else going mad like i did with mine. Seem's the clips on the HM and o rings fail so its worth checking just to be sure.
Hope this helps.
Ben
SpagettiDefender
Member
I bet you here's the source.
"I tried two torque wrenches set to 30 ft-lbs. All they did was beep and click and I could still tighten the bolt more. Those things don't work."
Correct stat fitted?it should have an extra bibble to cut off the bypass circuit as it opens.
Just because wpump is new should not discount it from your tests.
Viscous fan still fitted?
How did you bleed it?
If all else checks out I would get the head pressure tested with it hot.
Taking it off and flushing may be worthwhile. Thanks. Otherwise I can only think it’s the water pump.
the head was pressure tested hot.
viscous fan fitted
correct stat fitted. now removed and still overheats.
rad gets warm on side of inlet and outlet pipes only but hoses feel full of air only
