Bleeding the coolant system??

[paul 16v]

hi guys i wanna change my coolant/antifreeze before winter sets in is there any particular why to bleed the system??

 

[dave7368]

there is no bleed screw as such,
after you filled the rad,
run the engine with the rad cap off and the heater on max until the thermostat opens,
while keeping an eye on the level,
top up if needed, fit rad cap...
jobs a goodun

 

[Richtm]

this.

make sure you keep an eye on the coolant level as it will drop as the thermostat opens so you gotta be ready to top it up! also, keep an eye on the temp gauge and make sure the fan comes in a few times.

 

[paul 16v]

ok cheers guys!
i'll do that job my self then!

 

[VT-Doo]

I do it with the car facing up a hill so the air rises to the top front (radiator cap) of the engine.
The drain bolt is at the bottom passenger side of the radiator IIRC.
Once up to temperature I also hold the revs at a steady 3k rpm while a friend (girlfriend :lol: ) fills the radiator.
Take it for a spin, it's bled properly when all the hoses get hot.

 

[kazmo]

do it up hill???? :xlol: :xlol: :xlol: :xlol:

never did any like that and completely unnecessary!

:lol:

 

[mikegsi]

I do it with the car facing up a hill so the air rises to the top front (radiator cap) of the engine.
The drain bolt is at the bottom passenger side of the radiator IIRC.
Once up to temperature I also hold the revs at a steady 3k rpm while a friend (girlfriend :lol: ) fills the radiator.
Take it for a spin, it's bled properly when all the hoses get hot.

Yeah drain bolt is on the radiator itself, towards the bottom on one side, I can't remember for definate which side. Easy job to do though

 

[Richtm]

Uphill??? :lol: you muppet!!! Lol. U really think that helps?

Also, to drain it don't flaff about with the drain plug, pull the bottom hose off!!! 100 times quicker!! Rad cap off and let it run up to temp. :xcheers:

 

[mikegsi]

Uphill??? :lol: you muppet!!! Lol. U really think that helps?

Also, to drain it don't flaff about with the drain plug, pull the bottom hose off!!! 100 times quicker!! Rad cap off and let it run up to temp. :xcheers:

uphill gardening....

 

[dave7368]

Uphill??? :lol: you muppet!!! Lol. U really think that helps?

Also, to drain it don't flaff about with the drain plug, pull the bottom hose off!!! 100 times quicker!! Rad cap off and let it run up to temp. :xcheers:

uphill gardening....

:lol: :lol: :lol: does this mean we should be draining it facing downhill????
xrofl

 

[VT-Doo]

I'll entertain you lot.
With your car facing down hill, and having NO water in any of the pipes; do you think you think you can remove all the air in the system, include the heater matrix, just as easy as if the radiator cap was above the engine?

If you can't understand the logic behind the way I do it then don't try and mock me!
The way I do it works first time everytime and very quickly too.

 

[kazmo]

no mocking intended but its completely pointless....
correct me if i'm wrong, but every garage ive ever been to including honda dealers and tgm, there floors are flat and i'd bet my salary they bleed the cooling system with the car level :-"

:xspank:

 

[Richtm]

I'll entertain you lot.
With your car facing down hill, and having NO water in any of the pipes; do you think you think you can remove all the air in the system, include the heater matrix, just as easy as if the radiator cap was above the engine?

:lol: what do you think a water puimp is for? and with the pressure that builds up, all air will escape through an open point - the open rad cap (or most other cars - bleed screws in the thermostat housing and bleed points on a couple of pipes, but every honda ive worked on, and most jap cars infact, you run it up with the rad cap off).

seriously mate, if you dont know what youre doing, stop working on your car!

 

[mikegsi]

I drain mine on the flat, fill it up on the flat, let it run with the rad cap off on the flat till it's upto temperature then leave it 5-10 minutes running, on older cars I would leave it till the rad fans kicked in

 

[Richtm]

youre a mad man!!! you dont do it on a hill????? :lol:

 

[Stoo]

I see the logic, but it is a little daft.

 

[Richtm]

no logic...just daft and uneducated

 

[Stoo]

There is logic. Air rises in a liquid.
Basic physics.

It's a little harsh and uneducated of you to make an assumption of someone based on their personal techniques.

If having it on a hill helps him rest in the knowledge that there's no air in the system, so be it. It's not doing you any harm is it? You losing sleep?

 

[mikegsi]

There is logic. Air rises in a liquid.
Basic physics.

It's a little harsh and uneducated of you to make an assumption of someone based on their personal techniques.

If having it on a hill helps him rest in the knowledge that there's no air in the system, so be it. It's not doing you any harm is it? You losing sleep?

But will only rise to it's highest accessible point, it won't go round a level bend or follow pipework as it goes down to then cone back up.

With the engine running the water pump is pushing the water round the system together with the air bubbles that will then exit via the open radiator cap as they pass it...

 

[mikegsi]

Regardless of whether it's level, uphill or downhill, really makes no difference whatsoever