Cooling system
Discussion
I would like to know as much information about the cooling system as possible. Having changed all the hoses to silicon, and changed the water pipes, and heater pipes.
Today whilst having it running one water rail on the engine was hot the other cold, which isn't right i feel. I have been using the car since having austec bleed the system, i noticed a leak the other day on the belly pan, so have tighten the jubilee clips further, knowing that they would need doing as they need to bed in a bit, expansion / contraction etc.
I added a bit of water to the system to compensate for the small leak, roughly 250ml. the car up to temp today and the expansion bottle cap decided to poof steam, whilst i know they have a pressure relief in them its not right in doing that.
Whilst i have been using it, been up to silverstone and duxford and home last weekend, the gauge never showed above 82 degree. Heater goes from cold to hot as it should so coolant is circulating, all the pipes are getting hot as they should. rad top hose is cool until the thermostat opens, but can't understand why one coolant rail would stay cool whilst the other is hot when they share a common pipe, other than an air lock, which i guess could be why the expansion bottle is poofing as it is being worked out.
Both engine rails did get hot in the end, but i would have thought they would get to the same temp together, not one then the other. Or am i completely wrong.
Help and advice always welcome.
Today whilst having it running one water rail on the engine was hot the other cold, which isn't right i feel. I have been using the car since having austec bleed the system, i noticed a leak the other day on the belly pan, so have tighten the jubilee clips further, knowing that they would need doing as they need to bed in a bit, expansion / contraction etc.
I added a bit of water to the system to compensate for the small leak, roughly 250ml. the car up to temp today and the expansion bottle cap decided to poof steam, whilst i know they have a pressure relief in them its not right in doing that.
Whilst i have been using it, been up to silverstone and duxford and home last weekend, the gauge never showed above 82 degree. Heater goes from cold to hot as it should so coolant is circulating, all the pipes are getting hot as they should. rad top hose is cool until the thermostat opens, but can't understand why one coolant rail would stay cool whilst the other is hot when they share a common pipe, other than an air lock, which i guess could be why the expansion bottle is poofing as it is being worked out.
Both engine rails did get hot in the end, but i would have thought they would get to the same temp together, not one then the other. Or am i completely wrong.
Help and advice always welcome.
pmessling said:
I would like to know as much information about the cooling system as possible. Having changed all the hoses to silicon, and changed the water pipes, and heater pipes.
Today whilst having it running one water rail on the engine was hot the other cold, which isn't right i feel. I have been using the car since having austec bleed the system, i noticed a leak the other day on the belly pan, so have tighten the jubilee clips further, knowing that they would need doing as they need to bed in a bit, expansion / contraction etc.
I added a bit of water to the system to compensate for the small leak, roughly 250ml. the car up to temp today and the expansion bottle cap decided to poof steam, whilst i know they have a pressure relief in them its not right in doing that.
Whilst i have been using it, been up to silverstone and duxford and home last weekend, the gauge never showed above 82 degree. Heater goes from cold to hot as it should so coolant is circulating, all the pipes are getting hot as they should. rad top hose is cool until the thermostat opens, but can't understand why one coolant rail would stay cool whilst the other is hot when they share a common pipe, other than an air lock, which i guess could be why the expansion bottle is poofing as it is being worked out.
Both engine rails did get hot in the end, but i would have thought they would get to the same temp together, not one then the other. Or am i completely wrong.
Help and advice always welcome.
Blimey you scenario is exactly the same as mine done all the same as you, but had head gaskets changed as well, I was getting worried that the head gaskits had gone again,as it was doing the same as yours but touch wood I have bled the system again and now it has stopped doing it went for a short drive and left her ticking over for 20 mins and she was fine, I bled it to the radiator then both water rails, try that and see if okToday whilst having it running one water rail on the engine was hot the other cold, which isn't right i feel. I have been using the car since having austec bleed the system, i noticed a leak the other day on the belly pan, so have tighten the jubilee clips further, knowing that they would need doing as they need to bed in a bit, expansion / contraction etc.
I added a bit of water to the system to compensate for the small leak, roughly 250ml. the car up to temp today and the expansion bottle cap decided to poof steam, whilst i know they have a pressure relief in them its not right in doing that.
Whilst i have been using it, been up to silverstone and duxford and home last weekend, the gauge never showed above 82 degree. Heater goes from cold to hot as it should so coolant is circulating, all the pipes are getting hot as they should. rad top hose is cool until the thermostat opens, but can't understand why one coolant rail would stay cool whilst the other is hot when they share a common pipe, other than an air lock, which i guess could be why the expansion bottle is poofing as it is being worked out.
Both engine rails did get hot in the end, but i would have thought they would get to the same temp together, not one then the other. Or am i completely wrong.
Help and advice always welcome.
Could be just a case of bleeding the system more and make sure you don't fill expansion bottle to line as Cerbs seem to prefer running a lower level ! if i run mine to max line it blows steam out but no probs since dropping it down a bit.
Keep an eye on those water rail temps though as one being cold is not good IMO
Keep an eye on those water rail temps though as one being cold is not good IMO
Pete, when you say it stays at 82 degree, do you mean when on a run ? When you stop at the lights etc it goes up to 90 - 95 ish then the fans kick in to bring it down, if not then you may have thermostat stuck half n half.
I have a similar thing at the moment & have decided its the stat. Oh one thing , I had problems with silicone water pipe's ( not this car) & TBH wished I had stayed with the original rubber, the clips on the silicone pipes seem to work loose which let in air & all sorts of daft false boiling etc along with lots of head scratching? May have been cheap jubillee ?
I have a similar thing at the moment & have decided its the stat. Oh one thing , I had problems with silicone water pipe's ( not this car) & TBH wished I had stayed with the original rubber, the clips on the silicone pipes seem to work loose which let in air & all sorts of daft false boiling etc along with lots of head scratching? May have been cheap jubillee ?
I might be wrong but I think the coolant rails are on the return to the rad so the fact that they share a common pipe that returns to the rad makes no difference to what temperature each reaches. There are two impellers I think in the water pump and it may be that one feeds each bank so possibly a broken impeller blade.
It might also be quiet normal for an AJP but I am sure someone on this forum will let you know.
It can also be a arse to bleed so do it again.
It could be a whole host of things including mixture / throttle pots if one bank is running lean, gasket.
Have you got the ecu diagnostic software.
All the jubilee clips are proper jubilee clips, stainless ones so i didn't scrimp on cheap ones.
Thermostat is brand new, OEM part, and seem to be okay, as the top hose does get hotter and hotter, so is opening. although no way of telling if fully or stuck without removing it.
Of late haven't been stuck in any traffic, but whilst on the motor ways last weekend was always around the 80 degree mark, and never saw any 90s even when sitting at lights. It did reach 95 today when it vented steam, thats when i stopped it, i was only checking for a leak, and back to square one, pain in the arse.
I have the software so will double check on what temp the ecu is seeing compared to the gauge.
What are the fan temperatures?
Will try bleeding it again, and see how i get on with that.
Thermostat is brand new, OEM part, and seem to be okay, as the top hose does get hotter and hotter, so is opening. although no way of telling if fully or stuck without removing it.
Of late haven't been stuck in any traffic, but whilst on the motor ways last weekend was always around the 80 degree mark, and never saw any 90s even when sitting at lights. It did reach 95 today when it vented steam, thats when i stopped it, i was only checking for a leak, and back to square one, pain in the arse.
I have the software so will double check on what temp the ecu is seeing compared to the gauge.
What are the fan temperatures?
Will try bleeding it again, and see how i get on with that.
Pretty sure you have an airlock I'm afraid Peter which would suggest you have leak somewhere also
Mine has never puffed steam (as you describe) except when it had an airlock around the thermostat area. Ended up squeezing the hoses to move the coolant round to ensure the stat opened.
It would seem unlikely yours has this issue though as you've been driving it around...
Mine has never puffed steam (as you describe) except when it had an airlock around the thermostat area. Ended up squeezing the hoses to move the coolant round to ensure the stat opened.
It would seem unlikely yours has this issue though as you've been driving it around...
Header tank cap should vent at 1.5 bar. The actual coolant pressure will be above this at water pump out but I wouldn't go above the 1.5 bar.
This should show most leaks although if you do have a head gasket issue this would be aggrevated by heat and cylinder pressure so would be unlikely to show with a pressure tester.
This should show most leaks although if you do have a head gasket issue this would be aggrevated by heat and cylinder pressure so would be unlikely to show with a pressure tester.
Hi Pete,
FWIW I always bleed my system with the car on an incline (Nose Up).
Run up till the Thermostat is open.
Open the radiator bleed plug and ensure that all air is out.
Open Passenger-side Water Rail Bleed Valve until all air is out.
Open Driver-side Water Rail Bleed Valve until all air is out.
Topping up when necessary.
Repeat.
This has always worked.
I bought my silicon hose kit from ACT and their Jubilees were brilliant. No re-tightening necessary after initial fitting (but then again, I am rather ham-fisted)
Best of
FWIW I always bleed my system with the car on an incline (Nose Up).
Run up till the Thermostat is open.
Open the radiator bleed plug and ensure that all air is out.
Open Passenger-side Water Rail Bleed Valve until all air is out.
Open Driver-side Water Rail Bleed Valve until all air is out.
Topping up when necessary.
Repeat.
This has always worked.
I bought my silicon hose kit from ACT and their Jubilees were brilliant. No re-tightening necessary after initial fitting (but then again, I am rather ham-fisted)
Best of
I think the needing to tighten them may be due to using the jubilee clip tightening snake tool thingy, it doesn't really allow much tightening torque, have now tightened all with either a screw driver or 7mm spanner / socket
Found the pump hose clip was allowing a small amount of water out, so tightened, and pressure tested up to the 1.5bar, and didn't leak off, all hoses now dry, expansion bottle topped up, bleed the rad with the pressure tester still connected and got a lot of air out, ran the car up passenger water rail bleed no air at all, rad bleed again all good, drivers water rail, is nothing but steam, no water, so must still have an airlock.
Currently waiting on the car to cool down and will try again, but a good improvement so far.
Found the pump hose clip was allowing a small amount of water out, so tightened, and pressure tested up to the 1.5bar, and didn't leak off, all hoses now dry, expansion bottle topped up, bleed the rad with the pressure tester still connected and got a lot of air out, ran the car up passenger water rail bleed no air at all, rad bleed again all good, drivers water rail, is nothing but steam, no water, so must still have an airlock.
Currently waiting on the car to cool down and will try again, but a good improvement so far.
Boston rads did a recore on mine £150 and has been perfect, I also used the ACT hose kit and have had no problems with leaks.
Bleeding system such a critical part, just make sure only water seeping out of all bleed valves and you should be there, as said before I do mine with nose up slightly to help with bleed.
Ali rad is a must I guess if it's in your budget ! But a recore will work fine, still can't believe how much cooler mine runs in traffic after sorting cooling system ! I even used distiller water
Have you replaced temp sensor on hard pipes ? That's a must while your in there IMO
Bleeding system such a critical part, just make sure only water seeping out of all bleed valves and you should be there, as said before I do mine with nose up slightly to help with bleed.
Ali rad is a must I guess if it's in your budget ! But a recore will work fine, still can't believe how much cooler mine runs in traffic after sorting cooling system ! I even used distiller water
Have you replaced temp sensor on hard pipes ? That's a must while your in there IMO
Yeah new sensor in the water manifolds, but its interesting as the ECU sensor reads alot hotter than then SPA gauge. Once i've replaced my rad and bleed it AGAIN, i'll use a temp sensor and measure the different temps and compare to what it actually is, as i would have thought they would be the same, given that they are only about 2 inches apart.
Well having removed my rad to replace it, i have also replaced the aircon condenser, seems in okay ish condition but the fin's have started coming apart and the whole bottom row has come away, the actual rad is still intact just not the cooling fins. so thought as its only £100 might as well do it at the same time.
New radtec radiator from tvr power, who sent it back to radtec to get powder coated, should hopefully be able to fit and forget having the extra protection
Although a polished rad would look good, but given the F1 panel, you can't see it any way
Will be fitting it tomorrow, doesn't take long, having only fitted the old one around a mouth ago. Slim fan on first, rad in, then the bigger fan and connect up. Then the bleeding job.
New radtec radiator from tvr power, who sent it back to radtec to get powder coated, should hopefully be able to fit and forget having the extra protection
Although a polished rad would look good, but given the F1 panel, you can't see it any way
Will be fitting it tomorrow, doesn't take long, having only fitted the old one around a mouth ago. Slim fan on first, rad in, then the bigger fan and connect up. Then the bleeding job.
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