how do you remove air pocket in coolant system?

[daven611]

i have a 1991 legacy 2.2 , just change the water pump timing belt and cam shaft  and crank shaft seals, now trying to fill coolant system and can't get in to flow. 

any thiouights? 

 

or do i get a pressurize coolant system tool to fill it?

[silverback]

Did you change the thermostat with a genuine Subaru product? The thermostat has a 'jiggle valve' which is a small rod that hangs through a hole in the thermostat mounting flange. It has to be there and move freely.

 

You did not indicate how much coolant that you have been able to add to your system.

Did you try to add coolant through the upper radiator hose into the engine?

[lmdew]

It takes about 2 gallons, a little less,

Take a gallon of A/F and slowly fill the engine using the upper radiator hose and then put the hose on

Fill the over flow tank

Put the heater on high

Start the engine and slowly fill the radiator

When you think it's full, place your hand over the filler neck and burp the system.  Squeeze the top hose until bubbles stop coming out

Fill the system.

Put the cap on and let it come up to temp and then cool.  I will suck some coolant back in.  Keep an eye on the tank until it stops going down.

[nickb21]

+1 to what lmdew said.

 

I personally fill the rad as well, then start the engine and top off the rad.

 

I've always done this with the car pointed uphill, might not do anything, but I think it helps.

[Fairtax4me]

Most of the older cars have a bleeder cap on top of the radiator opposite the filler cap. Just a plastic screw with a large phillips head. If yours has it, remove it while filling the radiator until coolant flows out of it.

[johnceggleston]

copied from another forum.

 

how to fill and burp your cooling system.

taglines: burpcoolingsystem; suphonfill; burpcoolantsiphon.

compiled from previous posts:

PART 1>

1/ remove vent plug on radiator at top hose.

2/ fill radiator at fill neck / cap SLOWLY. (slowly is key.)
(i have written this a couple of times and it works great, for me. but
it is so odd and extreme i really don't expect any one to follow it. sit
the jug of coolant on the passenger strut tower and use a long tube,
about 1/4 inch diameter, to siphon the coolant in the rad. the process is so slow you will get bored, but slow works in this situation. )

3/ when full install the vent plug and rad cap.

4/ start the engine and run it up to full operating temp. then shut it down and wait for it to cool down.

5/ open the rad and top it off. mine usually only takes a couple 3-4 oz.
(most folks run the engine with the rad cap off to burp
it. but i have found that when it burps it looses more coolant than it
really needs to so i just heat it up and then let it cool before i
open it. all you really want to do is circulate the coolant and
eliminate any air bubbles. the siphon is so slow it really does not need much burping or topping off. this is different than most other fill and burp process. )

good luck.

PART 2>

the last 2 times i have filled an empty cooling system on an ej25
engine, i have used a very unusual method and have had NO problems and
have not had to burp.

i put the gallon of coolant on top of the engine, either the passenger
strut tower or the air box near the firewall. i then use a small
diameter tube (~5/16 inch, inside diameter) to siphon
the coolant out of the jug and into the rad. (it helps if the tube is
clear so you can see the coolant as it gets close to your mouth.) after
the jug is empty, i then start over with a half jug (2 qts.).

this is a very slow process because of the size of the hose, but more so
due to the very small difference in height. the system fills very
slowly and has time to back fill the engine thru the top rad hose. i
make sure the rad cap is at least level with or usually higher than the
rest of the rad. having the vent cap open helps too.

the first time i did it i tried to burp it but i ended up wit h less coolant in the system than when the siphon had finished. so this last time i just let the siphon do its thing and then put the cap on. no problems.

it works great, but it is really, really, slow. so i do it while i'm
finishing up the last little bits of whatever i'm working on.

this is so slow that if you did it and then watched it you would give up
and start pouring long before it got done. but it is a great time to
open a beer and admire your work.

i doubt this is a good technique for a car that needs to be burped, but it works great for filling empty systems.

HTH.


PART 3>

for 90s legacys, the small vent cap is the trick to filling correctly.
coolant WILL NOT flow into the upper rad hose / engine block unless you
have the vent plug removed. and even then you have to fill it SLOWLY.

once you have slowly added as much as it will take with the vent plug
open, close that, fill to the top of the rad and start the engine. when
the t-stat opens the coolant will burp
out of the rad and the level will drop. (in most cases it will drop, but
if you filled it slow enough the system MAY be full.) top it off and
put on the cap.

(my solution to filling slowly is to siphon
the coolant out of the jug and into the rad. i use a 1/4''- 3/8''
clear tube about 10 feet long that i bought years ago and i use it for
all of my siphoning needs. it fills the rad so slowly you get bored.
but you can rotate tires or change the oil while you wait. once it is
full, mine will not burp. it is full.)

on a side note:
if you used a non-subaru t-stat you are going to have trouble.
they do not work and it will over heat. i know some of you do not want
to believe this but it is true. i was one of them for a long time.

there are several parts on these engines that MUST be subaru. and hopefully you do not damage anything learning that.
SOMETIMES, not very often, a ''high quality'' replacement part will
work, but ''cheap'' aftermarket parts are never a good solution for
these ''subaru only'' parts. they end up not working correctly and you
not only have to redo the work (twice the labor) you have to buy
another, usually more expensive, part. buying parts twice is never cost
effective, even if your labor is free.

Edited February 3, 2014 by johnceggleston

[nipper]

Wow everything is so complicated, whne it is really easy. First off you need a chicken that was born on the night of a new moon when capricon is setting and venus is rising ... or

 

With the system drained and on level ground.

 

Start car.

SLOWLY add coolant (50/50 premix no tap water) until the radiator is full

Monitor the temp gauge and wait for some overflow from the radiator neck. This will indicate the T-stat has opened.

The coolant will go down and drop, now SLOWLY add more coolant till full.

Put cap on radiator.

Fill overflow to hot line.

 

Drive car around block, shut off, allow to cool.

 

Repeat after car cools off. 

 

That's it. This works on almost every car and has since the dawn of water cooled time. 

[daven611]

thank you all for the help  with this air pocket. 

i fixed it by getting a rad. vacuum tool  and pulled it down to -30 lbs pressure and then filled it with coolant and water in one bucket and dropping a hose to the bottom and opened the vavle , and it was full after a min or two. 

runs great and no over heating , accept at the heater as it should be.

again thank you all 

 nice to see there are good poeple willing to help