Bled cooling system but still no interior heat....

[MO525]

I just replaced the water pump, radiator, hoses, thermostat, cast alum. therm. housing and COMPLETELY drained the system (including the block plug), refilled with BMW coolant/distilled water 50/50.

Question is...I have put in 9.5 quarts now, the engine temp. is rock-steady, bled the system (at least I guess I did) but I still have no heat on the interior?
I never did get the "bubbles and wait for the steady coolant to come out" that the Bentley says about the bleeder.

Yes, this is my first time....if feel dumb as hell here but I'm really drawing a blank.

I'm assuming there must still be an air pocket in there.....probably the heater core area?

Thanks for any input/help.

[winfred]

once you get the thermostat to open it's blead, as for no heat most likely a dead aux pump, it's under the valves and easy to test just hook it to 12 volts and it runs. no pump no coolent flow through the core, path of least resistance and all

[Anton CH.]

Check my thread on passenger heat. Bill R shows a great way to test aux water pump.

[MO525]

Check my thread on passenger heat. Bill R shows a great way to test aux water pump.

And it's dead-on perfect on the "cold" line.

I will most certainly check the aux. pump.....better start reading on that one, not sure what it is, exactly. :)

Do I need to re-bleed after replacing/repairing the aux. pump?

I'll check that thread immediately.

Thanks!

[ryan roopnarine]

working properly before the system exploded? i don't make a living working on e34s, but i'd doubt that it is likely that the HCV would die just because you changed the antifreeze. what i would try first (if the heat was working properly before) is to bleed the system at the heater control valve. you would do this by disconnecting one of the hoses from the hcv. start the car with the heat on, and wait for the hose to begin (flowing) out coolant. at that point, stop the car, hook the hose back up, bleed at the radiator for safety's sake, and check whether or not you can feel heat in the car after restarting.

[MO525]

working properly before the system exploded? i don't make a living working on e34s, but i'd doubt that it is likely that the HCV would die just because you changed the antifreeze. what i would try first (if the heat was working properly before) is to bleed the system at the heater control valve. you would do this by disconnecting one of the hoses from the hcv. start the car with the heat on, and wait for the hose to begin (flowing) out coolant. at that point, stop the car, hook the hose back up, bleed at the radiator for safety's sake, and check whether or not you can feel heat in the car after restarting.

That is what makes me think there's a monster air bubble in there.
I was hoping....after the number of times I bled the darned thing....it was bled!!! Good heavens.

Great Idea, Ryan!
I'll do the bleed at the valve.
Sounds logical, I was just iffy on whether to do it.

[MO525]

once you get the thermostat to open it's blead, as for no heat most likely a dead aux pump, it's under the valves and easy to test just hook it to 12 volts and it runs. no pump no coolent flow through the core, path of least resistance and all

Would it go by another name?

Do they actually just DIE like that?
I had EXCELLENT heat before the cooling system repair/service.

[ryan roopnarine]

i don't think that its sold separately from the heat control valve, unless you buy used. not sure though.


Would it go by another name?

Do they actually just DIE like that?
I had EXCELLENT heat before the cooling system repair/service.

[Bill R.]

cooling system/ water cooling/ and then its about the 4 item down that page.
It says currently out of stock. Other online vendors show them for around 120. However I think your jumping the gun, if your heater worked perfectly before then I suspect the pump is fine. Did you originally bleed the cooling system with the heater controls turned to high and the fan on low? The manual specifies that you bleed it like that. And on some cars I have had to raise the front end to try and get the airlocks to come out. Jumper the aux pump relay so the pump runs all the time and bleed the cooling system again... or by jumpering it you'll find out if you have a bad aux pump.









i don't think that its sold separately from the heat control valve, unless you buy used. not sure though.

[mike wong]

I heard that the aux pump can be rebuilt, but I have no details.

[winfred]

64 11 8 390 090, Auxiliary Water Pump about $130 at dealer

[Unregistered]

Just replaced the auxiallry water pump on my 90 525I. Pretty easy to do. Had one heck of a time bleeding the system, but finally took the advice to open both the bleed screw on the expansion tank and the bleed screw on the thermostat. (Car not running). Literally blow into the fill opening on the radiator expanison tank until fluid comes out of the bleed screw on the thermosat housing (Effectively pressuring the system). Close the thermostat bleeb screw and continue blowing until fluid comes out of the bleed screw on the expansion tank. Then tighten that bleed screw. The system is completely bled.
Interesting though is that I ran the car, the temperature gauge was rock solid at 12:00. Still no heat. Ran around the block - hit a bump and heat started blowing out. Must have been a little air pocket in the heater core or lines. Works great now - ran from Rockford IL into Chicago and back just to test the system - perfect. Good Luck.

[winfred]

m20 e34s can be a bitch to bleed, one thing that helps is drilling a small hole in the thermostat, that breaks the vacuum and lets the block burp. i've gotten a few 525s in for head jobs because people roasted the engine thinking it will burp itself


Just replaced the auxiallry water pump on my 90 525I. Pretty easy to do. Had one heck of a time bleeding the system, but finally took the advice to open both the bleed screw on the expansion tank and the bleed screw on the thermostat. (Car not running). Literally blow into the fill opening on the radiator expanison tank until fluid comes out of the bleed screw on the thermosat housing (Effectively pressuring the system). Close the thermostat bleeb screw and continue blowing until fluid comes out of the bleed screw on the expansion tank. Then tighten that bleed screw. The system is completely bled.
Interesting though is that I ran the car, the temperature gauge was rock solid at 12:00. Still no heat. Ran around the block - hit a bump and heat started blowing out. Must have been a little air pocket in the heater core or lines. Works great now - ran from Rockford IL into Chicago and back just to test the system - perfect. Good Luck.

[MO525]

cooling system/ water cooling/ and then its about the 4 item down that page.
It says currently out of stock. Other online vendors show them for around 120. However I think your jumping the gun, if your heater worked perfectly before then I suspect the pump is fine. Did you originally bleed the cooling system with the heater controls turned to high and the fan on low? The manual specifies that you bleed it like that. And on some cars I have had to raise the front end to try and get the airlocks to come out. Jumper the aux pump relay so the pump runs all the time and bleed the cooling system again... or by jumpering it you'll find out if you have a bad aux pump.

Thanks for responding, Bill.
From all the reading I did, I bled with the heat on high and the fans on HIGH.
So the fans should be on LOW? I'll be darned.
I'll sure do it, NO problem.

If I have to jack up the car, I'll jack it up.
Gotta do what I gotta do.

Maybe this is a dumb request but could you possibly give me a schematic for the jumper?
I'd hate to botch THAT up! :(
I pulled the relay and the schematic on it is a bit vague...and TINY for reading, too!

I've still only put in 9-9.5 qts. of coolant in.
The level is PERFECT with the engine cold, though.
That is why I'm thinking "air pocket" somewhere.....oh, say about 2 qt. air pocket, possibly?

Thanks again.
I'll attack it again Tues. morning.
Just returned from a weekend vacation......flying, NOT driving! :D

[Bill R.]

http://www.bimmernut.com/%7Ebillr/images/auxpumprelay93.jpg
Thanks for responding, Bill.
From all the reading I did, I bled with the heat on high and the fans on HIGH.
So the fans should be on LOW? I'll be darned.
I'll sure do it, NO problem.

If I have to jack up the car, I'll jack it up.
Gotta do what I gotta do.

Maybe this is a dumb request but could you possibly give me a schematic for the jumper?
I'd hate to botch THAT up! :(
I pulled the relay and the schematic on it is a bit vague...and TINY for reading, too!

I've still only put in 9-9.5 qts. of coolant in.
The level is PERFECT with the engine cold, though.
That is why I'm thinking "air pocket" somewhere.....oh, say about 2 qt. air pocket, possibly?

Thanks again.
I'll attack it again Tues. morning.
Just returned from a weekend vacation......flying, NOT driving! :D

[MO525]

I'll tackle that first thing Tues. Morning.

[MO525]

Thanks for the pointers, Bill.

Once I jumpered those terminals, the pump started right up and gurgled like crazy....air pocket, anyone?.....
I'm SURE that got the fluid circulating 100% and I was able to add another 1.5 quarts.
Fantastic.

Temp. gauge is DEAD steady at approx. 11:00 position. Oh yeah!

[Unregistered]

For heater problems must be the aux. pump,
Go to this site, they show you how to change it!!

http://www.bmwe34.net/e34main/Maintenance/Electrical/HeaterValve.htm