Having tough time bleeding cooling system because I guess I don't know what I'm doing
#1
05-17-2016, 07:51 AM
Having tough time bleeding cooling system because I guess I don't know what I'm doing
I thought I knew what I was doing.
My 2003 Land Rover Discovery SE with 4.6L 107K mi was just fine no issues. I replaced the thermostat because it looked factory original and seemed about the right time.
I replaced the upper radiator hose, all three and t-connector, and new bleed screw. Came as one assembly. Replaced thermostat to engine J-hose with a flex hose. Clamped everything down no leaks. I figured if I was going through this, I didn't want to do it again anytime soon.
Now I cannot seem to get trapped air out of the system. I fill to cold level with 50/50 coolant and run until normal operating temperature with elevated expansion reservoir on top of battery tray. I open the reservoir cap and watch it rise until thermostat opens up. I rev the engine a few times 2000-3000. Bleeder screw closed. I pinch hoses to move trapped air. Then I shut down the engine and let cool overnight. Repeat Fri, Sat, Sun.
I drive 2-3 miles and go up this long hill to my house. At the top, I see the temp gauge starting rise. I pull over cool down then go back home.
It seems there's still trapped air.
QUESTION: When I warm up the engine to burp air, do I let the coolant bubble out? If so, how long? Or, do I shut the engine off after it reaches normal operating temperature and not let coolant bubble out? Do I warm engine with cap on reservoir and bleed steam out the bleeder screw instead?
I have since put the old thermostat back in because it was working fine before.
My 2003 Land Rover Discovery SE with 4.6L 107K mi was just fine no issues. I replaced the thermostat because it looked factory original and seemed about the right time.
I replaced the upper radiator hose, all three and t-connector, and new bleed screw. Came as one assembly. Replaced thermostat to engine J-hose with a flex hose. Clamped everything down no leaks. I figured if I was going through this, I didn't want to do it again anytime soon.
Now I cannot seem to get trapped air out of the system. I fill to cold level with 50/50 coolant and run until normal operating temperature with elevated expansion reservoir on top of battery tray. I open the reservoir cap and watch it rise until thermostat opens up. I rev the engine a few times 2000-3000. Bleeder screw closed. I pinch hoses to move trapped air. Then I shut down the engine and let cool overnight. Repeat Fri, Sat, Sun.
I drive 2-3 miles and go up this long hill to my house. At the top, I see the temp gauge starting rise. I pull over cool down then go back home.
It seems there's still trapped air.
QUESTION: When I warm up the engine to burp air, do I let the coolant bubble out? If so, how long? Or, do I shut the engine off after it reaches normal operating temperature and not let coolant bubble out? Do I warm engine with cap on reservoir and bleed steam out the bleeder screw instead?
I have since put the old thermostat back in because it was working fine before.
#2
05-17-2016, 08:00 AM
Baja
Bleed the system stone cold, raise the recovery tank and fill it to the top. Then pull out the bleeder screw and let the coolant drain for a few Minutes (it will make a mess,) while keeping the tank full, reinstall the screwgo for a ride on the highway. repeat the next morning stone cold if needed.
I thought I knew what I was doing.
My 2003 Land Rover Discovery SE with 4.6L 107K mi was just fine no issues. I replaced the thermostat because it looked factory original and seemed about the right time.
I replaced the upper radiator hose, all three and t-connector, and new bleed screw. Came as one assembly. Replaced thermostat to engine J-hose with a flex hose. Clamped everything down no leaks. I figured if I was going through this, I didn't want to do it again anytime soon.
Now I cannot seem to get trapped air out of the system. I fill to cold level with 50/50 coolant and run until normal operating temperature with elevated expansion reservoir on top of battery tray. I open the reservoir cap and watch it rise until thermostat opens up. I rev the engine a few times 2000-3000. Bleeder screw closed. I pinch hoses to move trapped air. Then I shut down the engine and let cool overnight. Repeat Fri, Sat, Sun.
I drive 2-3 miles and go up this long hill to my house. At the top, I see the temp gauge starting rise. I pull over cool down then go back home.
It seems there's still trapped air.
QUESTION: When I warm up the engine to burp air, do I let the coolant bubble out? If so, how long? Or, do I shut the engine off after it reaches normal operating temperature and not let coolant bubble out? Do I warm engine with cap on reservoir and bleed steam out the bleeder screw instead?
I have since put the old thermostat back in because it was working fine before.
My 2003 Land Rover Discovery SE with 4.6L 107K mi was just fine no issues. I replaced the thermostat because it looked factory original and seemed about the right time.
I replaced the upper radiator hose, all three and t-connector, and new bleed screw. Came as one assembly. Replaced thermostat to engine J-hose with a flex hose. Clamped everything down no leaks. I figured if I was going through this, I didn't want to do it again anytime soon.
Now I cannot seem to get trapped air out of the system. I fill to cold level with 50/50 coolant and run until normal operating temperature with elevated expansion reservoir on top of battery tray. I open the reservoir cap and watch it rise until thermostat opens up. I rev the engine a few times 2000-3000. Bleeder screw closed. I pinch hoses to move trapped air. Then I shut down the engine and let cool overnight. Repeat Fri, Sat, Sun.
I drive 2-3 miles and go up this long hill to my house. At the top, I see the temp gauge starting rise. I pull over cool down then go back home.
It seems there's still trapped air.
QUESTION: When I warm up the engine to burp air, do I let the coolant bubble out? If so, how long? Or, do I shut the engine off after it reaches normal operating temperature and not let coolant bubble out? Do I warm engine with cap on reservoir and bleed steam out the bleeder screw instead?
I have since put the old thermostat back in because it was working fine before.
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hemicharger69 (05-17-2016)
#3
05-17-2016, 08:20 AM
When you see the temperature gauge start to rise, you are at an engine damaging temperature. You really need to get a OBD temp monitor, otherwise trapped air will be the least of your worries. The dash gauge is not calibrated to reflect anything useful.
Try putting the heater on inside the car as you drive it after bleeding. Gets everything moving more than if it wasn't on. I had trapped air at the weekend and this solved it.
Try putting the heater on inside the car as you drive it after bleeding. Gets everything moving more than if it wasn't on. I had trapped air at the weekend and this solved it.
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hemicharger69 (05-17-2016)
#4
05-17-2016, 08:26 AM
Pro Wrench
Bleed the system stone cold, raise the recovery tank and fill it to the top. Then pull out the bleeder screw and let the coolant drain for a few Minutes (it will make a mess,) while keeping the tank full, reinstall the screwgo for a ride on the highway. repeat the next morning stone cold if needed.
Nope. I've don't this 100 times and still have high temps. I've even done a combination of this and the method below and have gotten a couple more cups in after I used this other method.
I don't even touch the overflow.
Green coolant.
I make the front bleed screw the highest point by parking the truck on a steep hill.
Turn on the heat, let the truck run. Squeeze the hoses touching the T and the two heater hoses.
Fiat spyders have a very similar cooling hose routing and this is how they do it.
OP what are the temps you're seeing?
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hemicharger69 (05-17-2016)
#5
05-17-2016, 09:52 AM
Super Moderator
When you see the temp rise it's more than likely the air pocket is at the intake manifold so the temp goes up since it's not measuring actual coolant temp vs air. If it continues to climb past 210F I'd shut it down and let it cool down.
If you keep getting air trapped in the system you may have a leak somewhere and it's putting air into the system. Does the coolant smell like fuel/oil? Are the hoses rock hard?
If you keep getting air trapped in the system you may have a leak somewhere and it's putting air into the system. Does the coolant smell like fuel/oil? Are the hoses rock hard?
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hemicharger69 (05-17-2016)
#6
05-17-2016, 10:05 AM
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hemicharger69 (05-17-2016)
#7
05-17-2016, 10:33 AM
I thought I knew what I was doing.
Try doing it as per LR's manual as first reply suggested. Your reservoir may need a bit of topping-off for two or three days after initial bleed due to the small amount of air left in the system. Always top-off or bleed system when stone cold to prevent air from entering the system.
Manual:
5. Release top hose from retaining lugs on the fan
cowl, leaving the hose to rest on the lugs.
6. Remove bleed screw from top hose.
l 'A' From 03 MY
l 'B' Up to 03 MY
7. Unclip the bleed hose from the battery box.
8. Remove expansion tank from its mounting
bracket. Slowly fill the expansion tank with
coolant, approx. 4 litres (7 pt).
9. Raise the expansion tank approx. 20 cm (8 in)
vertically, coolant will drain into the system.
10. Refill the coolant expansion tank until a steady
flow of coolant is emitted from the bleed hole.
11. Fit the bleed screw then, with the expansion
tank still raised, continue filling the system until
the coolant level reaches the base of the
expansion tank filler neck.
12. Fit expansion tank filler cap, fit the expansion
tank to its mountings and clip the bleed hose to
the battery box.
13. Refit the top hose into its lugs on the fan cowl.
14. Start and run engine until normal operating
temperature is reached, and check for leaks.
15. Switch off engine and allow to cool.
16. Check for leaks and top-up coolant to cold level
mark on expansion tank
cowl, leaving the hose to rest on the lugs.
6. Remove bleed screw from top hose.
l 'A' From 03 MY
l 'B' Up to 03 MY
7. Unclip the bleed hose from the battery box.
8. Remove expansion tank from its mounting
bracket. Slowly fill the expansion tank with
coolant, approx. 4 litres (7 pt).
9. Raise the expansion tank approx. 20 cm (8 in)
vertically, coolant will drain into the system.
10. Refill the coolant expansion tank until a steady
flow of coolant is emitted from the bleed hole.
11. Fit the bleed screw then, with the expansion
tank still raised, continue filling the system until
the coolant level reaches the base of the
expansion tank filler neck.
12. Fit expansion tank filler cap, fit the expansion
tank to its mountings and clip the bleed hose to
the battery box.
13. Refit the top hose into its lugs on the fan cowl.
14. Start and run engine until normal operating
temperature is reached, and check for leaks.
15. Switch off engine and allow to cool.
16. Check for leaks and top-up coolant to cold level
mark on expansion tank
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hemicharger69 (05-17-2016)
#8
05-17-2016, 10:34 AM
When you add coolant to the system to bleed, three things need to happen at the same time:
COLD ENGINE:
1) Park with your nose of the truck on a steep angle up, or on ramps. Front of the truck is the highest point.
2) Open bleed screw.
3) Raise expansion tank higher than everything else. Add fluid until no air is burping from bleed screw. Only coolant should flow from bleed screw hole.
Close everything
That's it. If you want to check the system later, wait until engine has cooled down and with the nose up, open the bleed screw carefully to see if any air escapes. Close the bleed screw hole.
If you need to top up coolant later you can add to the expansion tank as normal, but when filling/bleeding, both the expansion tank is raised AND the bleeder screw are open at the same time.
COLD ENGINE:
1) Park with your nose of the truck on a steep angle up, or on ramps. Front of the truck is the highest point.
2) Open bleed screw.
3) Raise expansion tank higher than everything else. Add fluid until no air is burping from bleed screw. Only coolant should flow from bleed screw hole.
Close everything
That's it. If you want to check the system later, wait until engine has cooled down and with the nose up, open the bleed screw carefully to see if any air escapes. Close the bleed screw hole.
If you need to top up coolant later you can add to the expansion tank as normal, but when filling/bleeding, both the expansion tank is raised AND the bleeder screw are open at the same time.
Last edited by jamieb; 05-17-2016 at 10:37 AM.
The following users liked this post:
hemicharger69 (05-17-2016)
#9
05-17-2016, 10:49 AM
When you add coolant to the system to bleed, three things need to happen at the same time:
COLD ENGINE:
1) Park with your nose of the truck on a steep angle up, or on ramps. Front of the truck is the highest point.
2) Open bleed screw.
3) Raise expansion tank higher than everything else. Add fluid until no air is burping from bleed screw. Only coolant should flow from bleed screw hole.
Close everything
That's it. If you want to check the system later, wait until engine has cooled down and with the nose up, open the bleed screw carefully to see if any air escapes. Close the bleed screw hole.
If you need to top up coolant later you can add to the expansion tank as normal, but when filling/bleeding, both the expansion tank is raised AND the bleeder screw are open at the same time.
COLD ENGINE:
1) Park with your nose of the truck on a steep angle up, or on ramps. Front of the truck is the highest point.
2) Open bleed screw.
3) Raise expansion tank higher than everything else. Add fluid until no air is burping from bleed screw. Only coolant should flow from bleed screw hole.
Close everything
That's it. If you want to check the system later, wait until engine has cooled down and with the nose up, open the bleed screw carefully to see if any air escapes. Close the bleed screw hole.
If you need to top up coolant later you can add to the expansion tank as normal, but when filling/bleeding, both the expansion tank is raised AND the bleeder screw are open at the same time.
The following users liked this post:
hemicharger69 (05-17-2016)
#10
05-17-2016, 11:18 AM
Got it.
I forgot to mention during bleed, I did have the heater on HI and nose angled up.
number9 you're right. I've been googling all this. Thanks for this manual excerpt
cappedup: yes, I'm only going by the dash gauge.
I didn't do step 10 in manual or step 2 according to Jamieb. I will do that tonight and report results tomorrow.
Thanks for the advice!
I forgot to mention during bleed, I did have the heater on HI and nose angled up.
number9 you're right. I've been googling all this. Thanks for this manual excerpt
cappedup: yes, I'm only going by the dash gauge.
I didn't do step 10 in manual or step 2 according to Jamieb. I will do that tonight and report results tomorrow.
Thanks for the advice!