Welcome to Bimmerfest -- The #1 Online Community for BMW related information! Please enjoy the discussion forums below and share your experiences with the 200,000 current, new and past BMW owners. The forums are broken out by car model and into other special interest sections such as BMW European Delivery and a special forum to voice your questions to the many BMW dealers on the site to assist our members!

Please follow the links below to help get you started!

Go Back   Bimmerfest - BMW Forums > BMW Model Discussions > 5 Series > E34 (1989 - 1995)

E34 (1989 - 1995)

Reply
 
Thread Tools Display Modes
  #1  
Old 12-02-2015, 03:16 PM
rdc rdc is offline
Russell
Location: Lexington, KY
 
Join Date: May 2006
Posts: 936
Mein Auto: 1995 525iA
heater valve test??

Is there a heater control valve test? I have warm air, not hot air. I had the pump replaced about 4 years ago so it should be ok. First time using heat this year and noticed it did not get very hot. Valves could be stuck.

Thanks, Russell
__________________

1995 525i auto, 1/95 build, EAT chip, abt 236K miles, , HID, Lumbar, Oxford Green/Parchment, rebuilt trany @ 211K
Reply With Quote
Advertisement
  #2  
Old 12-03-2015, 12:10 AM
capricornbmw capricornbmw is online now
Officially Welcomed to the 'Fest
Location: Many places
 
Join Date: Feb 2014
Posts: 1,661
Mein Auto: E36
Yes., Google for this. Actually I'll tell you what to do. The heater valves look like and 'X' when view from the top. They have four screws at each corner. Loosen each screw by 3 turns, then knock on the two valve 'towers' alternately, with medium force (it is not fragile). Make sure the heater is on in the car, the key is at key2, but the engine is off. Do this ten times then switch off and on the heat a further ten times. Then securely tighten down each screw in the correct pattern to ensure an even seal.

Knocking the valve towers would dislodge them if they were stuck.

Try the heat now with the engine running. If this doesn't work make sure all the heat vents and controls (there is one in the central vane panel that you need to roll up to hot, in fact do this first and see) and see if it is fixed. If not you may have to replace your heater valve unit.

Hey. I just remember. Check the E34 bible link at the top of these forums. Graybeard did a big repair on his heater valves recently it might help you down the line.
Reply With Quote
  #3  
Old 12-03-2015, 06:24 AM
rdc rdc is offline
Russell
Location: Lexington, KY
 
Join Date: May 2006
Posts: 936
Mein Auto: 1995 525iA
Thank you. I will give it a shot. However, what is the e34 bible link?
__________________

1995 525i auto, 1/95 build, EAT chip, abt 236K miles, , HID, Lumbar, Oxford Green/Parchment, rebuilt trany @ 211K
Reply With Quote
  #4  
Old 12-03-2015, 11:36 AM
capricornbmw capricornbmw is online now
Officially Welcomed to the 'Fest
Location: Many places
 
Join Date: Feb 2014
Posts: 1,661
Mein Auto: E36
Graybeard, could you post the link to your writeup here ? Thanks.
Reply With Quote
  #5  
Old 12-03-2015, 07:33 PM
Mr._Graybeard Mr._Graybeard is offline
Officially Welcomed to the 'Fest
Location: Wisconsin
 
Join Date: Oct 2011
Posts: 521
Mein Auto: '95 540i, E30, E24
My situation was that my valve set had a small coolant leak that got onto the wiring and ate up the copper leads. The result was full-on heat, so it likely doesn't apply here. I'd check the hoses leading into the firewall to see if they're getting hot. One or more of the vent or blending flaps may be stuck open, allowing too much cold air into the HVAC housing.
Reply With Quote
  #6  
Old 12-03-2015, 09:02 PM
rdc rdc is offline
Russell
Location: Lexington, KY
 
Join Date: May 2006
Posts: 936
Mein Auto: 1995 525iA
Thanks. i will do some checking in the next day or so. may need to take to my indy mechanic.
__________________

1995 525i auto, 1/95 build, EAT chip, abt 236K miles, , HID, Lumbar, Oxford Green/Parchment, rebuilt trany @ 211K
Reply With Quote
  #7  
Old 12-04-2015, 10:24 AM
TheEinstein's Avatar
TheEinstein TheEinstein is offline
Officially Welcomed to the 'Fest
Location: Denver, CO
 
Join Date: Mar 2014
Posts: 1,606
Mein Auto: E34 540i
Warm air, not hot, after even 20-30 minutes of driving? If the temp selector on the dash is set near the ambient temperature, you should hear the solenoids firing the valves intermittently in order to regulate the temperature/flow. That said, I've taken a few of those manifolds apart, and I'd say they could be seemingly working fine, but the seals at the valves be deteriorated. Do you get hot if you turn to heat? IOW, is the blowing air semi-controllable? If so, I'd wonder about the rubber valve seats being cracked up or even completely toasted. That or as Mr. Gray suggests, a mixer flap failure... Damn having to deal with those flaps. I'll change my heater core at the same time when, God-forbid, that crap goes south.
__________________
1995 E34 540ia
160,000 Miles
VIN# ...GF32404
Hellrot Red

Fuelly

My Basic Repair History (Edited 1/27/2015)

Ongoing comparison between two E34 540ia's

OBC4 Hidden Functions : Link
Reply With Quote
  #8  
Old 12-04-2015, 10:31 AM
rdc rdc is offline
Russell
Location: Lexington, KY
 
Join Date: May 2006
Posts: 936
Mein Auto: 1995 525iA
Quote:
Originally Posted by TheEinstein View Post
Warm air, not hot, after even 20-30 minutes of driving? If the temp selector on the dash is set near the ambient temperature, you should hear the solenoids firing the valves intermittently in order to regulate the temperature/flow. That said, I've taken a few of those manifolds apart, and I'd say they could be seemingly working fine, but the seals at the valves be deteriorated. Do you get hot if you turn to heat? IOW, is the blowing air semi-controllable? If so, I'd wonder about the rubber valve seats being cracked up or even completely toasted. That or as Mr. Gray suggests, a mixer flap failure... Damn having to deal with those flaps. I'll change my heater core at the same time when, God-forbid, that crap goes south.
Thank you. So far I have found only warm air with heater control max(red) and center vents full on (red) I may just replace the heater valve as it is original. About $150 Bosch and $300 plus OE. Yep, If I have to do a flapper or motor repair the heater core WILL be replaced. Itis the original.
__________________

1995 525i auto, 1/95 build, EAT chip, abt 236K miles, , HID, Lumbar, Oxford Green/Parchment, rebuilt trany @ 211K
Reply With Quote
  #9  
Old 12-04-2015, 11:07 AM
TheEinstein's Avatar
TheEinstein TheEinstein is offline
Officially Welcomed to the 'Fest
Location: Denver, CO
 
Join Date: Mar 2014
Posts: 1,606
Mein Auto: E34 540i
Never getting hot, and yet never getting cool, suggests a mix flap failure. I think those even respond when you do an HKL module test in CarSoft. In any case, I can't disagree with changing that valve out. No matter what, the connections get brittle on that assembly, and it has grounded my car since it's part of the entire cooling system.

FWIW, this link still works as of posting - ($114) http://www.ebay.com/itm/OEM-Bosch-He...-/351318454246
__________________
1995 E34 540ia
160,000 Miles
VIN# ...GF32404
Hellrot Red

Fuelly

My Basic Repair History (Edited 1/27/2015)

Ongoing comparison between two E34 540ia's

OBC4 Hidden Functions : Link
Reply With Quote
  #10  
Old 12-04-2015, 11:10 AM
rdc rdc is offline
Russell
Location: Lexington, KY
 
Join Date: May 2006
Posts: 936
Mein Auto: 1995 525iA
Quote:
Originally Posted by TheEinstein View Post
Never getting hot, and yet never getting cool, suggests a mix flap failure. I think those even respond when you do an HKL module test in CarSoft. In any case, I can't disagree with changing that valve out. No matter what, the connections get brittle on that assembly, and it has grounded my car since it's part of the entire cooling system.

FWIW, this link still works as of posting - ($114) http://www.ebay.com/itm/OEM-Bosch-He...-/351318454246
Thanks. I may not have been clear. Ac seems to work fine. However, i do not discount a mix-flap issue
__________________

1995 525i auto, 1/95 build, EAT chip, abt 236K miles, , HID, Lumbar, Oxford Green/Parchment, rebuilt trany @ 211K
Reply With Quote
  #11  
Old 12-04-2015, 01:51 PM
Mr._Graybeard Mr._Graybeard is offline
Officially Welcomed to the 'Fest
Location: Wisconsin
 
Join Date: Oct 2011
Posts: 521
Mein Auto: '95 540i, E30, E24
When I turn on AC and recirculate buttons with the car running, I hear a "thunk" as the exterior vent closes. Can you hear that when you turn on AC and recirc?
Reply With Quote
  #12  
Old 12-04-2015, 02:09 PM
rdc rdc is offline
Russell
Location: Lexington, KY
 
Join Date: May 2006
Posts: 936
Mein Auto: 1995 525iA
Quote:
Originally Posted by Mr._Graybeard View Post
When I turn on AC and recirculate buttons with the car running, I hear a "thunk" as the exterior vent closes. Can you hear that when you turn on AC and recirc?
Yes I do. However I think I found the real problem. I went to feel the hose connections as they go into the firewall and a hose came off the first nipple on the heater core connection. Looks lke it had partially corroded and broke off and the opening was partially filled with crud. I was able to reconnect the hose but it barely connected. Looks like a new heater core. I will have this done by an independent shop. My garage is not heated and I am bit old (72) to be contorting under the dash.
__________________

1995 525i auto, 1/95 build, EAT chip, abt 236K miles, , HID, Lumbar, Oxford Green/Parchment, rebuilt trany @ 211K
Reply With Quote
  #13  
Old 12-04-2015, 02:16 PM
TheEinstein's Avatar
TheEinstein TheEinstein is offline
Officially Welcomed to the 'Fest
Location: Denver, CO
 
Join Date: Mar 2014
Posts: 1,606
Mein Auto: E34 540i
Damn, sorry to hear that. I'm curious, and not that I want to debate it, but are you running BMW coolant?
__________________
1995 E34 540ia
160,000 Miles
VIN# ...GF32404
Hellrot Red

Fuelly

My Basic Repair History (Edited 1/27/2015)

Ongoing comparison between two E34 540ia's

OBC4 Hidden Functions : Link
Reply With Quote
  #14  
Old 12-04-2015, 03:55 PM
rdc rdc is offline
Russell
Location: Lexington, KY
 
Join Date: May 2006
Posts: 936
Mein Auto: 1995 525iA
Quote:
Originally Posted by TheEinstein View Post
Damn, sorry to hear that. I'm curious, and not that I want to debate it, but are you running BMW coolant?
No. I run Zerex G05. Have for years. BTW, the coolant was drained and refilled this summer. The heater core is original. When I bought the car 12 years a go, it had the green stuff. I changed it to BMW blue for a few years then the G-05.

I have also suspected the heater core was leaking a year or so ago. i would smell coolant every once in a while. Heat was never really good either. So just time to replace the heater core I think.
__________________

1995 525i auto, 1/95 build, EAT chip, abt 236K miles, , HID, Lumbar, Oxford Green/Parchment, rebuilt trany @ 211K

Last edited by rdc; 12-04-2015 at 03:56 PM.
Reply With Quote
  #15  
Old 12-04-2015, 07:35 PM
Mr._Graybeard Mr._Graybeard is offline
Officially Welcomed to the 'Fest
Location: Wisconsin
 
Join Date: Oct 2011
Posts: 521
Mein Auto: '95 540i, E30, E24
I use G05 too. I think it's a good substitute for BMW G48.

I don't blame you for taking the job to a shop. The core itself is not a terrible job, but snaking those tubes through the firewall looks like a pain. When I changed the heater core in my car I left the original tubes in. Sounds like you don't have that option.
Reply With Quote
  #16  
Old 12-04-2015, 10:08 PM
rdc rdc is offline
Russell
Location: Lexington, KY
 
Join Date: May 2006
Posts: 936
Mein Auto: 1995 525iA
Quote:
Originally Posted by Mr._Graybeard View Post
I use G05 too. I think it's a good substitute for BMW G48.

I don't blame you for taking the job to a shop. The core itself is not a terrible job, but snaking those tubes through the firewall looks like a pain. When I changed the heater core in my car I left the original tubes in. Sounds like you don't have that option.
Looks that way. I may disconnect the damaged tube and plug the hose for now. It appears to be the driver's side tube.
__________________

1995 525i auto, 1/95 build, EAT chip, abt 236K miles, , HID, Lumbar, Oxford Green/Parchment, rebuilt trany @ 211K
Reply With Quote
  #17  
Old 12-05-2015, 06:49 AM
capricornbmw capricornbmw is online now
Officially Welcomed to the 'Fest
Location: Many places
 
Join Date: Feb 2014
Posts: 1,661
Mein Auto: E36
OP,

a. Don't take the car to the indy just yet.
b. Do what I suggested with the heater valve unit. Right away. It will only take you like 10 minutes. Then try the heat.
c. Take a picture of the crud that you see in your pipes and post it here. A close up picture with good light, and good flash.
d. Remove some of that crud carefully with a flat head screwdriver. I have an idea for it that will probably salvage your heater system without repair if it is indeed plugged up. but we'll have to do some trials first.
e. You're smelling coolant from time to time not because of a leaky heater core - if that was the case you'd smell it all the time since its right there in the cabin. Your leak is probably due to untightened hose clamps or something else in the engine bay. Airflow does not always direct it to the cabin blower motor so you don't smell this all the time. Check all your hose clamps everywhere.

Report back after you've done all of this.
Reply With Quote
  #18  
Old 12-05-2015, 07:00 AM
rdc rdc is offline
Russell
Location: Lexington, KY
 
Join Date: May 2006
Posts: 936
Mein Auto: 1995 525iA
Quote:
Originally Posted by capricornbmw View Post
OP,

a. Don't take the car to the indy just yet.
b. Do what I suggested with the heater valve unit. Right away. It will only take you like 10 minutes. Then try the heat.
c. Take a picture of the crud that you see in your pipes and post it here. A close up picture with good light, and good flash.
d. Remove some of that crud carefully with a flat head screwdriver. I have an idea for it that will probably salvage your heater system without repair if it is indeed plugged up. but we'll have to do some trials first.
e. You're smelling coolant from time to time not because of a leaky heater core - if that was the case you'd smell it all the time since its right there in the cabin. Your leak is probably due to untightened hose clamps or something else in the engine bay. Airflow does not always direct it to the cabin blower motor so you don't smell this all the time. Check all your hose clamps everywhere.

Report back after you've done all of this.
May try that today. However the pipe nipple is broken off or corroded. Already pulled all the crud i could reach with a pick and screwdriver. Both sides of the car are cold so i think the entire core is plugged or the heater valve is malfunctioning. Looks like I still need to do heater core repair regardless. I just may disconnect and plug the problem heater hose so can confidently drive the car till I can fix it.
__________________

1995 525i auto, 1/95 build, EAT chip, abt 236K miles, , HID, Lumbar, Oxford Green/Parchment, rebuilt trany @ 211K
Reply With Quote
  #19  
Old 12-05-2015, 09:41 AM
capricornbmw capricornbmw is online now
Officially Welcomed to the 'Fest
Location: Many places
 
Join Date: Feb 2014
Posts: 1,661
Mein Auto: E36
Could you feed a garden hose into the broken off pipe and flush it forcibly, as best as you can ? Lets see what happens.

And how was the crud that you removed - hard? Powdery ? What colour was it ?
Reply With Quote
  #20  
Old 12-05-2015, 10:22 AM
rdc rdc is offline
Russell
Location: Lexington, KY
 
Join Date: May 2006
Posts: 936
Mein Auto: 1995 525iA
Quote:
Originally Posted by capricornbmw View Post
Could you feed a garden hose into the broken off pipe and flush it forcibly, as best as you can ? Lets see what happens.

And how was the crud that you removed - hard? Powdery ? What colour was it ?
The crud was brown, soft with what looked like smallish flakes of brown hard stuff. Perhaps part of the corroded and broken off pipe. I may try a back flush on both side of the heater core. Remember it has separate heating for each side of the car.

Remember the pipe to the driver's side is broken or corroded off and barely holds the clamp. Flushing may be an exercise in frutility.
__________________

1995 525i auto, 1/95 build, EAT chip, abt 236K miles, , HID, Lumbar, Oxford Green/Parchment, rebuilt trany @ 211K
Reply With Quote
  #21  
Old 12-05-2015, 07:34 PM
rdc rdc is offline
Russell
Location: Lexington, KY
 
Join Date: May 2006
Posts: 936
Mein Auto: 1995 525iA
All of you have been very Helpful. I am going to have my heater core repaired as needed after I check with my indy., However, i am going to replace my heater valve mysel just to have my heating system up to snuff so to speak.

I see oe bmw heater valve at $300 and up. I see a Bosch heater valve at about $150 Any reason to get OE over teh Bosch?
__________________

1995 525i auto, 1/95 build, EAT chip, abt 236K miles, , HID, Lumbar, Oxford Green/Parchment, rebuilt trany @ 211K
Reply With Quote
  #22  
Old 12-05-2015, 08:04 PM
capricornbmw capricornbmw is online now
Officially Welcomed to the 'Fest
Location: Many places
 
Join Date: Feb 2014
Posts: 1,661
Mein Auto: E36
Your heater core may not be a problem that requires professional reinstallation. Do you understand this ? Unless you have a leak in the heater core and there is no conclusive proof of this at all, if you can flush the crud out, all you need to do is to jbweld a fitting over the corroded fitting and adapt your hoses to it, if required. (Relatively) simple job that can be diyed.


======================

Hold the garden hose up to the pipe with your hands, no need to clamp it. Lets see if we can flush the sucker clean. And yes, a backflush on the heater core is a brilliant idea. You'll have to backflush the entire radiator as well to ensure that all the crud has been removed from your system. If you've never backflushed your radiator, this is a Good Thing to do anyway, it will clear both your radiator and your engine block of all floating and trapped debris that can be moved out by fast flowing water.

To backflush your radiator, just unclip the top end of the low radiator hose, loosen its bottom end, and turn the hose up towards yourself with the bottom end still connected, then tighten the bottom end again. Remove the bleed screw and the rad cap alone. Stuff a garden hose or something more powerful into the exposed part of the lower rad hose. Stopper it as best as you can with rags. Then start the water at full blast and let it run for 5 minutes. You don't need more than 5 minutes, and you dont need to let the engine run. Oh, of course, don't do this on a hot engine. If you just stopped driving, wait at least 15 minutes.

After doing all of this, refill with water alone, bleed with heat controls active and with the engine running (as stated in the bentley manual), and then close the rad cap run the engine till hot and activate heat and see if the problem is fixed. If it is then put in new coolant. If it is not, then its time for special diy measures (pm me if interested) or for the indy.

Last edited by capricornbmw; 12-05-2015 at 08:19 PM.
Reply With Quote
  #23  
Old 12-05-2015, 08:09 PM
capricornbmw capricornbmw is online now
Officially Welcomed to the 'Fest
Location: Many places
 
Join Date: Feb 2014
Posts: 1,661
Mein Auto: E36
Loosen and tap on the heater valves (refer to earlier post here on the proper procedure) while you're doing all of this as well. That is part of the complete salvage procedure. It will only take you an additional 10 minutes tops and you won't have to unduly contort your body.

And OEM is the same as Original, just without the bmw logo. BMW gets other people to make more 75% of the car, and they are the original equipment manufacturers - they make the parts for the original manufacturer of the vehicle. BMW takes those parts, stamps its own logo onto it, marks up the price by between 25-200% and resells it as original. Its the same part.

And bosch is an oem for many things on bmws.
Reply With Quote
  #24  
Old 12-05-2015, 08:20 PM
capricornbmw capricornbmw is online now
Officially Welcomed to the 'Fest
Location: Many places
 
Join Date: Feb 2014
Posts: 1,661
Mein Auto: E36
Hey......aren't you the dude who has a spare E34 ? A car that you had owned for 15 years and you decided to stop driving it as it was too rusted, and use for parts for your other E34 ?

How are you ?
Reply With Quote
  #25  
Old 12-05-2015, 10:22 PM
rdc rdc is offline
Russell
Location: Lexington, KY
 
Join Date: May 2006
Posts: 936
Mein Auto: 1995 525iA
Quote:
Originally Posted by capricornbmw View Post
Hey......aren't you the dude who has a spare E34 ? A car that you had owned for 15 years and you decided to stop driving it as it was too rusted, and use for parts for your other E34 ?

How are you ?
Nope. I have owned this car since 2003. Only e34 I have owned. E28 before this car.
__________________

1995 525i auto, 1/95 build, EAT chip, abt 236K miles, , HID, Lumbar, Oxford Green/Parchment, rebuilt trany @ 211K
Reply With Quote
Reply

See More Related BMW Stories


Forum Navigation
Go Back   Bimmerfest - BMW Forums > BMW Model Discussions > 5 Series > E34 (1989 - 1995)
Today's Posts Search
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On



Forum Jump


All times are GMT -7. The time now is 11:54 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2016, vBulletin Solutions, Inc.
© 2001-2015 performanceIX, Inc. All Rights Reserved .: guidelines .:. privacy .:. terms