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Bleeding cooling system after flush ( very important)

  • Thread starter Thread starter Mike97gt
  • Start date Start date Apr 9, 2006

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Apr 9, 2006
#1
  • Apr 9, 2006
  • #1
I have seen several posts from people saying they bled there cooling system and have had cooling system issues after. these issues include

1. lack of heat

2. temp gauge never reaching normal temp

3. pinging while driving

4. overheating.

All of these issues are caused by not bleeding the cooling system after you drain the coolant. Anytime the system is drained when you fill it trapped air will remain in the coolant. If this trapped air is not removed then you will have poor cooling system performance and severe engine damage may result.

The best way I found to bleed the system is using a compressed air operated bleeding tool that pulls a vacuum on the system and then you fill into the vacuum. This is a 150 dollar kit and unless you work on a lot of cars I don't suggest you buy this kit.

The way I do it without a bleed kit is to fill the system and then run the car with the cap off the expansion tank and the heater on full blast out the dash vents. while bringing the engine rpm's run the engine at 1500 rpm's or so and let it burp the air out and add coolant as needed, then when you feel strong steady heat out the vents top it off and put the cap back on.
 

Stang|ess

seeking cyber partner(s)
Oct 18, 2003
941
0
37
Hawaii
Apr 9, 2006
#2
  • Apr 9, 2006
  • #2
Q: Is it necessary to rev the motor? I let it reach operating temps (95-99*C was what I reached before the flush, and is what I'm at now), the upper radiator hose is hot (T-stat opened), and hot air blows from the vents (used it last night. Hawaii is chilly ).

I also raised the front end, and no more fluid could go in.
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Apr 9, 2006
#3
  • Apr 9, 2006
  • #3
Stang|ess said:
Q: Is it necessary to rev the motor? I let it reach operating temps (95-99*C was what I reached before the flush, and is what I'm at now), the upper radiator hose is hot (T-stat opened), and hot air blows from the vents (used it last night. Hawaii is chilly ).

I also raised the front end, and no more fluid could go in.
Click to expand...


you should be fine then, you only raise the rpms if you have a hard time getting a air pocket out.
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Apr 10, 2006
#4
  • Apr 10, 2006
  • #4
ok I am going to unsticky this now, everybody should have seen it by now and we don't need to cluter up the top of the board with obvious stuff like this. I did add this to the important threads sticky.
 
T

Torinalth

Founding Member
Jul 16, 2002
952
0
16
Clayton NC
Apr 11, 2006
#5
  • Apr 11, 2006
  • #5
i had this done to my car by jiffy lube a while back, and come to think of it my detonation started either at that time or not long after... i think i might give this a go and see if i can bleed more air out. i have noticed my rez getting a bit empty, but no pooling of fluid on the floor... so i assume i did have a good bit of air... i'll have to give it a go. thanks for the info.

Torinalth
 

DropTopPony

Noob Slayer
Founding Member
Aug 13, 2002
2,570
3
48
south jersey
Apr 11, 2006
#6
  • Apr 11, 2006
  • #6
good info:
I always run mine with the cap off/heat on even if i'm topping off the coolant.
 
S

SigmaPride

New Member
Mar 31, 2005
170
0
0
Apr 12, 2006
#7
  • Apr 12, 2006
  • #7
Last time I changed my coolant I tried running the engine with the cap off. When it got up to operating temp coolant was bubbling out all over the place, so I stopped doing that. I just kept topping it off after driving it the next couple days until it stayed full. Does anyone else have this problem with it bubbling out?
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Apr 12, 2006
#8
  • Apr 12, 2006
  • #8
Torinalth said:
i had this done to my car by jiffy lube a while back, and come to think of it my detonation started either at that time or not long after... i think i might give this a go and see if i can bleed more air out. i have noticed my rez getting a bit empty, but no pooling of fluid on the floor... so i assume i did have a good bit of air... i'll have to give it a go. thanks for the info.

Torinalth
Click to expand...


You should check it right away.

personally I would rather set my car on fire than let jiffy lube touch my car.


SigmaPride said:
Last time I changed my coolant I tried running the engine with the cap off. When it got up to operating temp coolant was bubbling out all over the place, so I stopped doing that. I just kept topping it off after driving it the next couple days until it stayed full. Does anyone else have this problem with it bubbling out?
Click to expand...

yeah thats normal, the traped air will force some coolant out with it while it's coming out, I bled many many cars that way I got a vacuum bleeder.

doing the bleeding with the cap on can be done but it's extremly dangerous if you don't know what your doing. So I suggested the method thats safer but makes a bigger mess.
 
B

bdcardinal

tree hugger
Jun 10, 2003
3,612
16
69
santa barbara, CA
Apr 12, 2006
#9
  • Apr 12, 2006
  • #9
at least our cars arent the 6.0 PSDs. a friend of mine does heavy line and has pictures of them running the trucks at WOT for 30+ minutes with the rad cap off trying to get the oil in the coolant to burn off.
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Apr 12, 2006
#10
  • Apr 12, 2006
  • #10
bdcardinal said:
at least our cars arent the 6.0 PSDs. a friend of mine does heavy line and has pictures of them running the trucks at WOT for 30+ minutes with the rad cap off trying to get the oil in the coolant to burn off.
Click to expand...


we have had many many problems with the 6.0 deisel. ask your friend if he has seen any where the coolant and the oil mix turing into a milkshake.. lots of fun let me tell you.
 
B

bdcardinal

tree hugger
Jun 10, 2003
3,612
16
69
santa barbara, CA
Apr 12, 2006
#11
  • Apr 12, 2006
  • #11
ya, i hear about them and am glad i never had to deal with the 6.0s except for oil changes. apparently the new 6.4 TT diesel should be interesting.
 
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