Bleeding Cooling System

[jimmy01]

just wanna know where and how many bleed pionts does the rb26 have?

[Moodles2]

The most accessable one is the one near the fuel pressure regulator, I believe there is another in between the exhaust manifold but it's a drain bolt.

[Galois]

do a search mate, there's been a few topics along this line lately (would give an answer but haven't done it myself yet)

[jimmy01]

found the block drain point and attempted to undo it.. snapped both the socket and the wrench i was using. so i guess ill just have to bleed to motor and hopefully get all the air out and old coolant

[Wacky Dee]

forget the bleed valves they're hopeless and messy .... just take an empty coke bottle, cut the bottom off of it and lodge it firmly into the radiator opening. Poor coolant in and let the engine run for 10-20 minutes. You'll see a shitload of air come out as the coolan circulates through the engine and pushes the air out.

As for draining the old coolant ... just drain from the radiator or bottom hose (with car not running of course) ...dilute with demnieralized/distilled water as many times as you can until you see clear water coming out only. Then add your coolant concentrate.

[jimmy01]

forget the bleed valves they're hopeless and messy .... just take an empty coke bottle, cut the bottom off of it and lodge it firmly into the radiator opening. Poor coolant in and let the engine run for 10-20 minutes. You'll see a shitload of air come out as the coolan circulates through the engine and pushes the air out.

As for draining the old coolant ... just drain from the radiator or bottom hose (with car not running of course) ...dilute with demnieralized/distilled water as many times as you can until you see clear water coming out only. Then add your coolant concentrate.

too easy bro cheers

[dorifticon]

OK I did a search on "radiator" and "bleed" and this was the most relevant thread.

I too am a bit confused about the procedure for bleeding the rb26 (in an R32 GTR - actually its an rb26/30, but anyway).

This thread looks to be talking about opening the bleed screw with a socket.

Based on the descriptions of where the bleed screw is, mine seems to be an allen head bolt (near a small gold sticker that says "never open while hot" - which is near the fuel pressure reg).

Maybe someone replaced it? anyway. My questions are:

1) Is my descrption of the bleed screw location right? Maybe I should post a picture?

2) what is the actual procedure for doing the bleeding? eg do you crack the bleed screw while the motor is cold and let it get up to temp, or will it push air out simply because the water pump is operating and the bleed screw is between the water pump and the thermostat? Or is it some other procedure?

3) how does one prevent coolant from pouring out the bleed screw and all over the engine bay?

4) any other hints?

[MrStabby]

Maybe someone replaced it? anyway. My questions are:

1) Is my descrption of the bleed screw location right? Maybe I should post a picture?

2) what is the actual procedure for doing the bleeding? eg do you crack the bleed screw while the motor is cold and let it get up to temp, or will it push air out simply because the water pump is operating and the bleed screw is between the water pump and the thermostat? Or is it some other procedure?

3) how does one prevent coolant from pouring out the bleed screw and all over the engine bay?

4) any other hints?

1. Yes that's it. Mine is a hex head tho, directly above the gold sticker.

2. Cold stopped engine, fill radiator, open bleeder, wait until coolant comes out, close bleeder, top up radiator. I've never bothered to have it run at all, let alone warm it for bleeding.

3. Just be careful, you'll only get a slow flow and you stop it by replacing the bleed bolt. Its not a problem - you're over thinking it

4. Just be careful not to overtighten the bleeder and snap the bolt. BTDT.

[89CAL]

So having your thermostat closed means no air will be trapped in the system? You need to run the engine while topping up coolant

Crack bleed screwFill radiator till you can't anymore, start engine and run, top up as needed, you will know when the thermostat is open as you will be able to see water flowing across the top of the radiator by looking in the fill point. It will be still water when the thermostat is closed and you'll see it moving when it's open. After this just keep topping up till there is steady water coming out of the bleed point (no bubbles)

[MrStabby]

So having your thermostat closed means no air will be trapped in the system? You need to run the engine while topping up coolant

Yeah you're probably right. Thermostats dont seal, but to clear any air pockets you'll want full flow. FWIW when i've re-checked after bleeding my way, there's only been a tiny bit more air, whereas when you first crack it after draining, there's a ton of air in there.

[SargeRX8]

I bled mine doing pretty much everything above(bar the coke bottle). Let the car idle and warm up with bleeder open and lid off. Gave the pipes some squeezing to encourage any little trapped bubbles to come out. Also took it for a 20minute drive. Don't get scared but you can open the bleeder a tiny bit after a 15min drive. I did. Believe me the amount of air that came out was amazing before coolant came out. Under pressure and heat the air will travel to the highest point in the system(the bleeder) just crack it, literally one to two turns you will hear pssssst sound. Jiggle the screw and you will see bubbles of coolant seeping out. Just wait til you see abit more coolant come out.

Be cautious about this, if you take it too far you will get coolant shooting out and its f**king hot. Have a rag or towel handy and be cautious!!

I have a question of my own.

The first time I done my coolant, I heard like water in the cabin, I'm suspecting its water flowing through the heater core because it happened alot when revving. Its literally the sound of water flowing and sometimes taking a sharp turn it made the sound. Kind of like a half empty bottle in the car(there wasn't).

This is all gone after my second bleed, I think.

[MrStabby]

I have a question of my own.

The first time I done my coolant, I heard like water in the cabin, I'm suspecting its water flowing through the heater core because it happened alot when revving. Its literally the sound of water flowing and sometimes taking a sharp turn it made the sound. Kind of like a half empty bottle in the car(there wasn't).

This is all gone after my second bleed, I think.

Another good point - putting the heater on full is also a good idea, especially if you're changing/flushing coolant.

[blue_vl_t]

i'll summarize the above point and advise on what i usually do as i seem to have work on these frequently now.

fill water, derr

stick a funnel or coke bottle or old radiator hose with enough tape around it so when you jam it into the radiator cap hole it seals without leaking, this must be higher than your bleed screw or there will still be air in the system.

fill your funnel up and bleed the air, remove the screw until only coolant comes out and replace it.

I usually start the engine, turn your heaters on flat out keep topping up the water as it takes it.

then drive around the block, just so the engine is to temperature and carefully do the same again, or you can get away without a funnel as there is pressure in the system that will push the air from the bleeder, but carefully, will be hot.

I have see people crack the head on their car from not bleeding the air from the system, no need worry too much, it really is a very basic principal.

i'm usually anal enough to re check it after a week or so also

hope this helps

[Nismaniac]

hey guys i have an rb30 with heating issues, she heats up while driving and cools while idle, i have just replaced the thermostat and have tried everything mentioned above to bleed the air out, i then took it for a drive and she still sits on about 3/4 temp the next thing i will try is to replace the radiator but only if i have to, any ideas be appreciated cheers.

[StevenCJR31]

hey guys i have an rb30 with heating issues, she heats up while driving and cools while idle, i have just replaced the thermostat and have tried everything mentioned above to bleed the air out, i then took it for a drive and she still sits on about 3/4 temp the next thing i will try is to replace the radiator but only if i have to, any ideas be appreciated cheers.

it could be a blocked radiator but you you can create an artificial high point in your cooling system by running your car up on some car ramps ?

[Nismaniac]

cheers will try that if the new radiator doesn't fix the prob, i discovered a hole in the old 1 and already having issues i thought i might as well replace it and try kill 2 birds with 1 stone, fingers crossed it will work, i am expecting it to arrive this week or nxt