Cooling system rebuild - now no heat?

[cparker]

So I did the big stage 3 ECS cooling system overhaul kit, that included pulleys, tensioners, sensors, radiator, reservoir, hoses, thermostat, etc. and I followed the procedure in the Bentley manual to bleed the system but I still feel like there's a flow issue. The temp gauge came up to temp very quickly, within a couple minutes, and I have no heat.

Do you guys have any ideas as to what may be going on? I drove around for a few minutes and there were no signs of overheating but I was afraid to drive very long.

[danewilson77]

Sounds like bad t-stat.

Sent from Williamsburg, VA USA

[cparker]

I swapped the t-stat back in but same behavior. When the motor got to full temp I could feel the radiator return hose get hot like the t-stat opened and the entire radiator is hot.

I'm scratching my head on this one.

[danewilson77]

Ok. I think you need to continue to bleed. How much coolant did you put in?

Sent from Williamsburg, VA USA

[cparker]

Bled some more. Absolutely no bubbles coming out of the bleed screw now. Brought it up to temp, both rad hoses are hot and the fan is cycling on and off as if the motor is maintaining good temps (since our temp gauges are worthless I don't have a good way to check), but the heater lines both seem to be cold. I pulled the heater valve and it's not stuck closed.

Still no heat. I have to assume this is related to the work I performed and most likely an air issue but I haven't used my heat in a couple months so I may just now be discovering an older problem.

[cparker]

I've added about 2.5 gallons so far but that includes quite a bit of bleeding. I did not take the extra steps to drain the motor of coolant so there probably was some residual.

[danewilson77]

Wow. System is a 2 gallon system. How are you performing the bleed. Shit like this sucks.

[cparker]

Bled it through the bleed screw by the res. A lot of the loss was from swapping t-stats.

Sure enough, I drove it around some more after bleeding the hell out of it and a block down the street I hear some gnarly gurgling sounds and the heat starts working. It was just air.

Thanks for the help.

[danewilson77]

Good deal. Sometimes it's a bitch to bleed e46.

[LivesNearCostco]

Maybe didn't have vent dial in full red position with key "on" and heater set to highest (91F) while bleeding?

[danewilson77]

Maybe didn't have vent dial in full red position with key "on" and heater set to highest (91F) while bleeding?

And fan on low. Maybe?

Sent from Williamsburg, VA USA

[llll1l1ll]

Maybe taking a couple of turns sort of moved that bubble out of the heater area.

[telijah]

So weird, on other cars bleeding was a pain for me, but on my E46 I have yet to have a bleeding problem, yet everyone else seems to. Glad it was only a bleeding problem. The only other thing I would have suggested was maybe tapping that water valve under the hood...

[BimmerWill]

Glad it sorted itself out. Had the same issue with mine when I overhauled the cooling. Took it a little around the block and it fixed it right up after I bled it again.

Sent from my DROID BIONIC using Tapatalk 2

[danewilson77]

Since we're talking bleed.......I cannot stress enough.....when people do a complete drain on their cooling system, how important it is to pour the new coolant (50/50 mix) in as slowly as possible. I mean S L O W........

[redwagon]

I"ve been getting better at this but still far from 100% performance. Last time I did a drain on mine, I really tried to follow everything recommended in my manual and this forum super carefully and still it took a week or so of driving before things stabilized on coolant level...bubbles must have been in there somewhere.
Tim

[telijah]

Not sure if it is beneficial, but I've always "burped" the system while filling it with the upper hose.

[Beau B]

Did you try to bleed it with the front elevated? That worked for me, when I did mine a few weeks ago.. glad you got it all sorted out.

[brettbimmer]

Good deal. Sometimes it's a bitch to bleed e46.

Thanks DW. Good to know as I did the water pump, thermostat, engine block drain today, and I am having a hell of a time with the bleeding the air out of the system. Temp. keeps creeping up...more air comes out...repeat... Hopefully she will be stable by next weekend. :biggrin

[echo46]

When you filled the system and started to bleed, did you have the front of the car elevated and heat and blower on high? Really helps. Also, as Dane said when you are filling the BMW blue coolant (50/50 with distilled water) go really, really slow. After I feel the block and tank is fairly full, I start my engine and keep the bleeder screw and cap off. Now you should see bubbles coming out of bleed screw and up from expansion tank when you look down. Next, and be very careful, slowly and gently squeeze the upper and lower radiator hoses to get all the trapped air. BE CAREFUL. Be patient and wait till you see no more bubbles. I have used this method many many times and have never had an issue after complete.

[telijah]

While the temp is set to high, the blower should be on low... At least that's what AllData use to say to me.

[jayjay_dee]

When you filled the system and started to bleed, did you have the front of the car elevated and heat and blower on high? Really helps. Also, as Dane said when you are filling the BMW blue coolant (50/50 with distilled water) go really, really slow. After I feel the block and tank is fairly full, I start my engine and keep the bleeder screw and cap off. Now you should see bubbles coming out of bleed screw and up from expansion tank when you look down. Next, and be very careful, slowly and gently squeeze the upper and lower radiator hoses to get all the trapped air. BE CAREFUL. Be patient and wait till you see no more bubbles. I have used this method many many times and have never had an issue after complete.

I think the highlighted statement is the key here, worked for me when I did my cooling system refresh.

[brettbimmer]

Thank you all. I have done everything mentioned except raise the front of the car, but that makes good sense to help the air work it's way up and out of the system. Lots of air with the block drained. Added about a gallon of BMW blue coolant and distilled water, but probably have some more to add, once the air gets bled out of the system.

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[Hornung418]

I've discovered that ifthe you just raised the driver side front the air bleeds much quicker.

Horney...via TT.