Cooling System Bleeding
Discussion
Hi all,
What's the best way to bleed the cooling system on a 96 Griff (Serp). I understand the process abt loosining the radiator bleed nut, but don't understand why this is so.. wouldn't air be higher up in the system. The radiator bleed nut is actually quite low .. the top of the swirl tank and heater feeder lines are higher than the radiator.. isn't that where air would be trapped?
I have read on some other forums (not TVR releated but RR Discovery) that the car needs to jacked so the radiator is the high point in order to bleed the cooling system. Does this relate to TVR too?
Many thanks..
What's the best way to bleed the cooling system on a 96 Griff (Serp). I understand the process abt loosining the radiator bleed nut, but don't understand why this is so.. wouldn't air be higher up in the system. The radiator bleed nut is actually quite low .. the top of the swirl tank and heater feeder lines are higher than the radiator.. isn't that where air would be trapped?
I have read on some other forums (not TVR releated but RR Discovery) that the car needs to jacked so the radiator is the high point in order to bleed the cooling system. Does this relate to TVR too?
Many thanks..
My process is as folows ..
1 - Undo the bottom radiator hose (lowest easily accessible hose)
2 - Undo both swirl and expansion caps
3 - I wouldn't necessarily undo the rad bleed nut now, but you can.
4 - I then tend to wash the system through with a hose from down the swirl pot.
Refilling ..
1 - re-fit cap to expansion tank
2 - undo the bleed nut on the radiator(if not done already)
3 - fill with coolant until required amoun tin the system
4 - make sure not to lose through bleed nut (once it is running out without air then do it up and leave it)
5 - Continue to fill until no more will fit
2 methods from here ..
My dad made up an extended funnel arrangement on the end of 12" of pipe that screws into the top of the swirl pot, and so it become the highest point of the system, use that to fill.
or ..
Fill to the maximum in the swirl pot squeezing the top hoses to try and get any more air out of the system ... then remove expansion cap and replace swirl pot screw and run the engine at idle, and allow the system to work the air out of the system through the expansion tank. run for 5-10mins keeping an eye on Temp gauges etc and then refit expansion cap. turn off car and check the level in the swirl pot.
There should not be any pressure in the system as you have had the expansion cap off, any deficit in the system can then be filled through ..
The system takes around 7-8litres from memory and therefore it is useful to add water in measured amounts so you know exactly how much water and coolant has gone in so you know whether you are close to it's capacity or not.
Hope this helps ..
1 - Undo the bottom radiator hose (lowest easily accessible hose)
2 - Undo both swirl and expansion caps
3 - I wouldn't necessarily undo the rad bleed nut now, but you can.
4 - I then tend to wash the system through with a hose from down the swirl pot.
Refilling ..
1 - re-fit cap to expansion tank
2 - undo the bleed nut on the radiator(if not done already)
3 - fill with coolant until required amoun tin the system
4 - make sure not to lose through bleed nut (once it is running out without air then do it up and leave it)
5 - Continue to fill until no more will fit
2 methods from here ..
My dad made up an extended funnel arrangement on the end of 12" of pipe that screws into the top of the swirl pot, and so it become the highest point of the system, use that to fill.
or ..
Fill to the maximum in the swirl pot squeezing the top hoses to try and get any more air out of the system ... then remove expansion cap and replace swirl pot screw and run the engine at idle, and allow the system to work the air out of the system through the expansion tank. run for 5-10mins keeping an eye on Temp gauges etc and then refit expansion cap. turn off car and check the level in the swirl pot.
There should not be any pressure in the system as you have had the expansion cap off, any deficit in the system can then be filled through ..
The system takes around 7-8litres from memory and therefore it is useful to add water in measured amounts so you know exactly how much water and coolant has gone in so you know whether you are close to it's capacity or not.
Hope this helps ..
just dont let your animals lick it, one teaspoon of anti freeze is enough to kill a german shephard sized dog! out of interest i dont want to dissagree with johno but extending the header tank on a griff doesnt work that well, the reason being is because of the stat, if air is trapped in the engine it cant back feed through the rad so it gets pushed up into the heads and inlet manifold, if you take off the outlet pipe to the heater next to number 2 injector and fill the system as normal, when the header tank is full, put a wrag over the header tank and blow the water around the system whilst keep topping the header tank untill water comes out the removed pipe, put it back on fire the engine up and just top it up as needed!
didn't the Romanians top up their wine with anti-freeze? Rich...cinquecento said:Think of your central heating system. When you drain that and refill it you still have to bleed the rads downstairs even though they are lower that the rads upstairs! Air gets trapped in loads of places. Rich...
I understand the process about loosining the radiator bleed nut, but don't understand why this is so.. wouldn't air be higher up in the system. The radiator bleed nut is actually quite low ..
Griffith 500 overheating (?) problem.
I have one of the last 100 of the griff run-out cars with 11000 miles on the clock. The temperature gauge has often been a bit erratic, showing 75 - 80 during normal running with 95 - 105 in traffic, then often not going below 85 when back on the open road. Did a 60 mile trip in Surrey mid-day yesterday with no problems, but on the return journey after 30 miles on the open road doing 75 -80 mph lots of steam from the rear of the car but the gauge showing only 80 odd degees. A check under the bonnet showed plenty of coolant over the engine. After cooling off for 10 minutes, a check on the coolant level showed still a couple of inches in the expansion tank. Topped up with only 1/3 pint of water and got home OK with the heater full on. Temp. gauge stayed at 80 all the way home, including in traffic. Question is, what caused the apparent 'boil up' / loss of water? Dodgy thermosat or header tank (Blue) cap perhaps? I have noticed small amounts of coolant under the car 10 -20 mins after parking up, which would appear to be coming from the header tank cap area. Note that the header tank was still half full when the car had cooled off back at home.
I have one of the last 100 of the griff run-out cars with 11000 miles on the clock. The temperature gauge has often been a bit erratic, showing 75 - 80 during normal running with 95 - 105 in traffic, then often not going below 85 when back on the open road. Did a 60 mile trip in Surrey mid-day yesterday with no problems, but on the return journey after 30 miles on the open road doing 75 -80 mph lots of steam from the rear of the car but the gauge showing only 80 odd degees. A check under the bonnet showed plenty of coolant over the engine. After cooling off for 10 minutes, a check on the coolant level showed still a couple of inches in the expansion tank. Topped up with only 1/3 pint of water and got home OK with the heater full on. Temp. gauge stayed at 80 all the way home, including in traffic. Question is, what caused the apparent 'boil up' / loss of water? Dodgy thermosat or header tank (Blue) cap perhaps? I have noticed small amounts of coolant under the car 10 -20 mins after parking up, which would appear to be coming from the header tank cap area. Note that the header tank was still half full when the car had cooled off back at home.
davidstarkey said:
I have noticed small amounts of coolant under the car 10 -20 mins after parking up, which would appear to be coming from the header tank cap area. Note that the header tank was still half full when the car had cooled off back at home.
Half full is the correct level for the Griff this leaves room for expansion, perhaps you have simply over filled it and it's blown the excess coolant out?
davidstarkey said:
A check under the bonnet showed plenty of coolant over the engine.
Do you have air-con? Could also be water from that? Edited by richb on Monday 30th April 12:38
richb said:
davidstarkey said:
I have noticed small amounts of coolant under the car 10 -20 mins after parking up, which would appear to be coming from the header tank cap area. Note that the header tank was still half full when the car had cooled off back at home.
Half full is the correct level for the Griff this leaves room for expansion, perhaps you have simply over filled it and it's blown the excess coolant out?
davidstarkey said:
A check under the bonnet showed plenty of coolant over the engine.
Do you have air-con? Could also be water from that? Edited by richb on Monday 30th April 12:38
richb said:
davidstarkey said:
I have noticed small amounts of coolant under the car 10 -20 mins after parking up, which would appear to be coming from the header tank cap area. Note that the header tank was still half full when the car had cooled off back at home.
Half full is the correct level for the Griff this leaves room for expansion, perhaps you have simply over filled it and it's blown the excess coolant out?
davidstarkey said:
A check under the bonnet showed plenty of coolant over the engine.
Do you have air-con? Could also be water from that? I do not have air-con. The header tank may have been slightly over filled, however the car got stinking hot (105-ish)on the way down when crawling through High Wycombe without any loss of coolant. The 'cloud of steam' occured on the way back whilst on the open road at 75-80 mph (just prior to joining the M25) with an indicated temp. of 80 deg. It was the smell of hot glycol that brought my attention to the problem rather than the temp. gauge. By the way, when I pulled over and checked under the bonnet the fans were not operating, so its all a bit of a mystery. When the engine runs hot I get nervous - I had the water pump gasket blow out a couple of years ago (on the M25) and dumped all of the coolant. I had just returned from a night flight and collected the car from Gatwick TVR on the way home. Needless to say the griff went back to Gatwick TVR on a trailer....
Edited by richb on Monday 30th April 12:38
davidstarkey said:
It was the smell of hot glycol that brought my attention to the problem rather than the temp. gauge.....
Needless to say the Griff went back to Gatwick TVR on a trailer.
That's a shame, it's clear from posts on here that they are sensitive but by the time they were fitted with the twin fans I thought they had got it right. It could be the otter switch gone, especially if the fans don't seem to be cutting in. You can test this by running the car up to 90 deg' and then pulling the wires off the back of the switch and shorting them together with a paper clip or similar to see if the fans come on. Also worth knowing that the otter switch can go partially wonky i.e. work sometimes and not others, they don't always fail completely! That happened to me and I thought oh, it can't be the otter switch because the fans were working but on occasions they didn't! Swapped it and all has been fine since. Needless to say the Griff went back to Gatwick TVR on a trailer.
Gassing Station | Griffith | Top of Page | What's New | My Stuff