randedge New Reader
11/4/23 3:26 p.m.

Good day,

I just replaced some of the coolant on my 2010 Mitsu Outlander daily.  I bled it using the coolant burping funnel available from Napa - worked great on my IS300, worked great on this one too.  In the Mitsu Outlander, I don't think I missed any bleeder screws in the block, as I have a factory shop manual and could not find anything about it (unlike an MR2, which to my memory, has about four bleeder screws scattered throughout the block, heater core, radiator, and some piping above the transmission)

Anywho, once warmed up, I still keep getting air trapped between the rad cap and the line to the reservoir. As in, I can SEE it. (See: 1st pic)

To burp this pocket of air so that it doesn't return back to the cooling system as the coolant cools down and contracts, I have been unbolting the reservoir tank itself, lifting it above the rad cap, and turning it sideways, without spilling anything, thus allowing that pocket of air to escape and bubble out.  (see: awesome illustration as depicted in 2nd pic)

I've done this somewhat unique "burp air from overflow line" twice and that pocket of air kept coming back. Its size is slightly different each time, but then again, I've been having wild temperature swings here between freezing at night, and sunny sweater weather during the day.

Right now, the rad cap is new and if that pocket of air comes back once warmed again, I feel like something else might be wrong....?  I'm not losing coolant though, and it doesn't seem like I'm overcooling nor am I overheating. I don't think I have a BHG (I mean, I hope not), the car isn't down on power, no weird idling. Heater core blows hot air - important as I live where we'll be  getting real Canadian winter real soon, eh?

What else could be wrong? Does it really take that long to get rid of ALL the air out of a system that got drained and refilled? None of the other coolant burping jobs I've had to do to cars in my ownership history have had this problem.



wvumtnbkr PowerDork
11/4/23 5:36 p.m.

Hole in hose from rad to overflow?  Even a little one could do that.

randedge New Reader
11/5/23 6:49 p.m.

randedge New Reader
11/5/23 6:51 p.m.

Update. I ziptied the hose I had to take off for the aforementioned repair. It just never felt as tight as it was when I took it off first time it left Japan 13 years ago. 


I haven't seen an air pocket yet. :) 

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