Hi..i had a leak on a hose that came from my heater matrixs..i seen the water dripping and tightened the hose clip and stopped the leak..now i have a air lock and the car heats upto 3/4 the way on the temp guage instead of half way like it used to and when i first start her from cold i some times hear a gurgling noise from behind my heater controls/matrixs..i have had the rad cap off and engine running with heaters on but it is still there and it is some times drawing the water from my expansion tank..any one know how to burp the system..many thanks.
Bleeding the cooling system
- Thread starter andycanman
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Ok thanks..will try this.
Running heat makes no difference. Heater cores are always hot.
Running rough trails with steep inclines, declines and bumps in low gear should help.
I always refill my system through the upper radiator hose, air seems to come out nicely that way.
These systems are designed to collect air at the top of the radiator. When the coolant heats up, some coolant can overflow into the expansion tank through the overflow tube at the radiator cap. That automatically bleeds/purges air from the system. Some coolant is drawn back into the system when the coolant system cools. Keeping the overflow tank at the proper level (not full) will bleed air out every time the system goes from cold to hot to cold. Check it in the morning when it's stone cold, if the expansion tank is empty check the radiator is full.
These systems are designed to collect air at the top of the radiator. When the coolant heats up, some coolant can overflow into the expansion tank through the overflow tube at the radiator cap. That automatically bleeds/purges air from the system. Some coolant is drawn back into the system when the coolant system cools. Keeping the overflow tank at the proper level (not full) will bleed air out every time the system goes from cold to hot to cold. Check it in the morning when it's stone cold, if the expansion tank is empty check the radiator is full.
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- #8
Ok thanks..have tried squeezing hoses no joy,my expantion tank was topped up to the full mark and is now back to the low mark..where does the water go if i have no leak as radiator is still full..thanks...ment to add when engine was hot the hoses were soild why is this is it cause of the hot water inside as when it cooled a bit the hoses became soft.
Odd thing, but my overflow tank stays at the low mark. If I fill it to the full mark when cold, next time I check it's back at the low mark. I gave up trying to figure it out. No evidence that it overflows, and it never drops below the low mark. It must be overflowing...?
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- #10
yip thats what mine does...
Wouldn't that be a sign of a coolant leak, external or internal? i.e. that you're refilling coolant and it's dissappearing?
Or it could be a leak in the expansion tank - maybe just above the low mark??
Doesn't seem to be leaking when full, can sit for a day like that. Drive it around a couple days and it's down to the low mark. Has stayed at the low mark for over a year without losing any more, so it's not likely a coolant leak. I suspect an oops in the design of the expansion tank, haven't worried about it.
I ask b/c I noticed after TB job on mine I've refilled the overflow tank twice so far - I attributed the first and maybe even this second to the refill (maybe trapped air if that makes sens), but if it happens again I'm afraid maybe I've got a leak or a bad radiator cap or something (my understanding is the cap functioning properly is critical for the closed system to work properly).
I have no external leaks either, but if we're refilling and it's going back to low there's an external or internal leak by definition, right (or radiator cap isn't holding pressure correctly)?
I don't think the overflow tank staying at Low means anything - if it's so low that overflow tube can't reach the fluid I think only air would go back into the system. And if you're leaking somewhere internally (i.e. coolant in engine oil, engine block, or tranny fluid) I don't think you can judge by the level of the overflow tank.
Again, the reason I'm concerned is b/c I'm seeing same thing as you - refill once ok, but if I keep refilling and it keeps going to low I KNOW that is not normal and it would seem to mean there's a leak... From everything I've read coolant leak = serious.
I've got my eye on mine, will report back if I find out anything definitive.
If you have the funds or like buying tools, this is a nice device to have (but hard to justify if don't use it much)
It pulls vacuum in the cooling system and then fills the cooling system with no air locks.
Downside is the price plus you need a air compressor. I use it on every car I work on that involves cooling system work.
Or find a shop that has one and ask them to help you pull the air out of the system, it takes 5-10 mins so it shouldn't cost you much.
https://www.matcotools.com/Catalog/toolcatalog.jsp?cattype=T&cat=2281&page=4𐊺
An alternative is to get the front end of the car significantly higher than the rear end. Either park on a incline or lift the front end in the air and support with jack stands and let it warm up with the heater valve open and purge with the radiator cap off. The goal is to get the radiator cap neck higher than any cooling system line. I've tried this on a few vehicles before, but haven't tried it on a 100-series before..
It pulls vacuum in the cooling system and then fills the cooling system with no air locks.
Downside is the price plus you need a air compressor. I use it on every car I work on that involves cooling system work.
Or find a shop that has one and ask them to help you pull the air out of the system, it takes 5-10 mins so it shouldn't cost you much.
https://www.matcotools.com/Catalog/toolcatalog.jsp?cattype=T&cat=2281&page=4𐊺
An alternative is to get the front end of the car significantly higher than the rear end. Either park on a incline or lift the front end in the air and support with jack stands and let it warm up with the heater valve open and purge with the radiator cap off. The goal is to get the radiator cap neck higher than any cooling system line. I've tried this on a few vehicles before, but haven't tried it on a 100-series before..
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Well, after refilling the overflow tank total of twice plus a little top off, my coolant level's been consistently full. I didn't appreciate how much air could be trapped if the system is not filled/burped properly. I tried to burp after the TB job but didn't really know how to do it proper. Tool below would be nice, but not worth the cost to me at this point - I'm pretty sure I can do a better job of burping next time I have to refill (How To Find & Fix Coolant Leaks has a good description of burping and refilling until all air is gone from system - while you wait rather than driving around for days, then checking and topping off etc... the way I did this time).
Btw, I always kept my eye on coolant temp gauge and it never went above the 4.5 bar line where it usually stays. The first few days after TB I did drive around with OBD scanner to see the actual temp and b/f TB I don't think I ever was above 185, after TB it would jump as high as 190 (gauge didn't show any difference though). For fun I'll check again now that it appears to be fully burped to see if stays at 185 as b/f or maybe the thermostat is slightly different temp (I can't remember but think there's a range of acceptable temps for the thermostat).
looks like there are cheaper versions of the type of tool out there. Here are two:
Robinair 75260 Coolant Refiller with Air Lock Preventer#
or
UVIEW 550500, AirLift II Economy Refiller - DJV Merchandise.com
both ~$75. Are they any good compared to the more expensive tool RPMLX470 mentioned?
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