Air in coolant problem!?!?

dac69er

Super Moderator
Never had issues in the past, so I don't know why it is causing me so much grief now.

Changed the water pump over the winter and now I seem to have air in the system that just won't budge!

If I leave the car idling or off for a little while and then blip the throttle I can hear a rushing water sound through the heater matrix.


Previously I have simply filled the coolant up, started the car. Run it until the coolant starts to rise in the rad and I get no more bubbles and it's been fine. This time it just doesn't seem to want to shift.
Coolant level rises and then falls again in the expansion tank as it should. Heating works, albeit perhaps a little cooler than expected, but still hot.
Engine temp seems fine according to the gauge, the fan cuts in and out as it should.
I have no leaks that I can see anywhere.

Any ideas? Ive never had issues with this before on a starlet......
 

Jay

Admin
Never had many issues before Duncan, although I noticed over the last year my auto has had the same gargling noise on start up (it moves like 30ft every weekend so hardly a good comparison).

Tried raising the nose when bleeding? I hear the MR2's are an absolute bitch to bleed at times.
 

dac69er

Super Moderator
I'm with you jay, never had an issue in 15 years of owning starlets. It's just this occasion that is odd.

I did a 100mile trip today and it still did it after that.
I have tried raising the front and no luck, no extra bubbles come out. I may need to do it when stone cold though as the level kept rising as it was heating up so was a bit of an arse.

I've had it on my rx8 after draining the coolant and my fiat did it when the heater matrix was leaking, but this took a few weeks to start after it had lost enough coolant and drawn some air in.

Maybe it will sort itself out. Or get worse so I can actually find a problem!
 

gv1.3

Admin
My mr2 was a pain in the arse for this... Switch the engine off and gurgle gurgle gurgle though it never seemed to cause an issue with cooling. There were little bleed tubes in the frunk and a whole convoluted procedure for bleeding it if I recall.

Are you losing any coolant at all or is it staying level when you top it off?
 

SKINY

Lifer
When I changed to the Half Rad I just topped her up, rad cap off, heaters on full tilt until it warmed up, let it sit tick over with cap off and just topped it up to the level, strange one
Gen 7 celica and mr 2 are a bitch, you have to lift the expander bottle out and hang it up :mad:
 

dac69er

Super Moderator
My mr2 was a pain in the arse for this... Switch the engine off and gurgle gurgle gurgle though it never seemed to cause an issue with cooling. There were little bleed tubes in the frunk and a whole convoluted procedure for bleeding it if I recall.

Are you losing any coolant at all or is it staying level when you top it off?
I havnt really done a huge amount of mileage since replacing the waterpump, but level seems to stay the same once cooled. As mentioned, no leaks that I can find either.

It's not doing it badly. If I drove normally, I probably wouldn't really notice it. It's only as I initially bring the revs up to 3k ish that I hear it and then it won't do it again unless I leave it to idle for a bit and do it again or stop the car for a similar amount of time???
 

SKINY

Lifer
Is the heater valve opening and closing properly, it may be sending some back.to the bottle hence the noise ?
 

dac69er

Super Moderator
Is the heater valve opening and closing properly, it may be sending some back.to the bottle hence the noise ?
Sending some back to the bottle?????? The bottle is only for expansion of the coolant in the system.

It gets hot and it gets cold depending on the knob position.
 

dac69er

Super Moderator
Turn the radio up! :)
Any chance it could be a dodgy radiator cap?
Small possibility I guess, but as the expansion bottle is raising and dropping as it should with no boiling over issue etc, I would say it is ok. Its a brand new toyota one aboit 7 years ago and thr car doesnt do many.miles. i could always try a spare one though, just to be sure.
 
like the others indicated i've had to raise the front of my ep91 in the air to help bleed the system, else i get extremely high idle.
sometimes in the past i tried to squeeze tight the coolant hoses going to the radiator for a very short period (one hose at a time), but they get very hot, even with gloves.
when i had the stock radiator i don't recall having these issues (but that is a long time ago), since i switched to a custom made radiator and then the half sized radiator i've had this issue of bleeding the system....

PS my heater is bypassed, but the air seems to get stuck in the automatic choke area
 
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dac69er

Super Moderator
This particular gt is all fairly stock and as I said, never had any issues before!

Idle is fine so seems like there is no air in that area.

After work today I took the cap off and started the car up to let it run open from cold. Didn't really get any air out that I could tell but once I got home it appeared to be slightly better.
I will keep an eye on it as it may work it's way out anyway.

If not I will try and raise the front up as high as I can and see if that dislodged the air bubble!
 

Ryan H

Fresh Recruit
Thinking I may have a similar issue as my car is getting hot on a hill near me..
Thinking it must be air as it's perfect everywhere else in traffic etc
 

dac69er

Super Moderator
Well over time it has sorted itself. I don't get the issue anymore anyway.
Odd i have never had an issue before.

Have a leak from the rear main now. It was a brand new seal a few 100 miles ago and now it's pissing out :(
 
Well over time it has sorted itself. I don't get the issue anymore anyway.
Odd i have never had an issue before.

Have a leak from the rear main now. It was a brand new seal a few 100 miles ago and now it's pissing out :(
yeah, overtime it can bleed itself, but it can take a while before it does, so that's why we try to get it done faster with the different bleeding techniques mentioned before----sometimes even a real spirited drive (trashing) may work.

is the seal a genuine/OEM Toyota seal? i found the non-genuine ones don't work very well at all...also, I've found that even with OEM seals, the cam and crank shaft seals can sometimes give a very small weep rather quickly, but its never anything major (just an intermittent drop)....however, if yours is leaking really badly, then that's another matter and it will need replacing...make sure the surfaces are well clean and take your time installing them to avoid damage and to get it to sit flush in the space...on a side note, these car are rather old now, so i wonder if the 3 seal housings, cam and crank itself where the seals meet the spinning surface may have very micro wear overtime just from the billions of rpms over the years and thus cause the odd "marginal weep"....yeah, i know its metal parts vs rubber seals, but its just something i wonder about
 

sx_turbo

Lifer
i always used to fill the heater matrix first by taking 1 pipe off the stat housing, i then filled the rest of the engine via the top hose, then run engine squeeze pipe a few times, then rev engine a couple of times once it appeared there was no air left replaced the cap, go for a drive round the block. never had a problem doing it this way.
 

Skalabala

Member +
Always remember to put rubber grease on a new seal. Otherwise the crank will burn the seal.
And for the air lock, sometimes it takes a few spirited driving sessions to fix it :p
 
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