Questions about heat, cooling...

[eastsidebimmer]

I'm in the process of a move and it is darn cold, so I took my 68 2002 to my trusted independent BMW mechanic for an oil change and a once over before I send it into hibernation for the winter. I’ve owned this car since September, so I really haven’t had a chance to use the heat, but I tested it in the warmer months and it seemed very hot. Fast forward to now, I was driving it to the shop last week (about 30 degrees ambient) and:

#1 I found that I had more heat coming out of the passenger side than the driver. My side felt wimpy warm to cool and the passenger side was nice and warm. The defrost, when enabled, also felt cool.

#2 The fan motor sounds fine on low and makes a wail on high, usually only if I’m coming to a stop, and sounds better when I get back to speed. I think I understand why, but is there a fix for this?

#3 The heat gauge was just north of “middle” with the heat on driving at full at speed. (In the warmer months, the gauge never went above the middle with the heat off)

#4 Mechanic said coolant was only good for +5 degrees, and did not look new, so he flushed and filled. Said a new radiator might help the heat. This did not seem to help on the return trip home.

(How do I find out about the Curtis Radiator upgrade, or what is the best place to find 320i or even stock radiators, thermostats?)

Any ideas or tips? This is not a winter use car, but I’d like to be able to diagnose and fix if possible.

Ben

Eastsidebimmer (soon to be Northsidebimmer)

[Mike Self]

1. Sounds like the drivers side heat outlet door is partially blocked with crud and/or disintegrating foam seals, or it's not opening. Scrunch down there and shine a flashlight up the outlet; be prepared to pull crud out and/or loosen up a stuck outlet door.

2. Heater blower on 68s (and '69s thru 1664760) only have two speeds; sounds as if yours needs oil on the armature shaft. You can just about reach it with a 3 in 1 oil can from inside the heater plenum chamber (base of windshield). Pop off the plastic motor cover and you can see the armature end.

3. Temp gauge should run at about 3 o'clock with or without heater unless it's very cold or very hot. Your 68 may still have the small 4 blade cooling fan; you can cheaply upgrade to the later "tropical" 5 blade fan. It helps.

4. A new radiator won't help your heater's heat output; a new thermostat might (esp if you still have the old brass 'stat vs the later diecast zinc ones). But if you're getting good heat temp from the pax side outlet, you should get the same from the driver's side unless one side is either plugged up or not opening.

Curtis posts on this board all the time; his 3 row core radiator will solve any overheating problems you might have, but it doesnt' sound like you have an overheating problem.

Happy troubleshooting.

mike

[02fanatic]

And be sure to lubricate the heater control valve as best you can get at it! I recently pushed the slide control over on my '73tii and I thought it might break! ....egad!!...fortunately it loosened up and the heat began flowing well!. Man, talk about THE WORST '02 repair - heater box removal! Avoid this job if possible by being careful with those slide controls and lubricate the heater control valve frequently.

[Mike Self]

control valve control back and forth once a week or so in the summer--same as you're supposed to turn on your A/C periodically in the winter just to keep things loosened up.

Ya really don't want to take yer heater apart--especially on the early cars that don't have the easily removed dash controls...voice of experience here!

mike

[eastsidebimmer]

(nt)

[Beaner7102]

You may need to give your heater core a good flush, if its blocked hot water cant flow and heat the passing air. I had my rad recored and heater core flushed at the same time - I have to turn it down now its too hot. Also the temp should go down a fraction with the heater on as the water going through the heater core is being cooled (heating the air). I would check for crud in the heater flaps, also pull the defrost tubes and give them a blast with compressed air to clean out the crud. and if you want to go all out, its not that big a deal to pull the heater box, just folow the FAQ How-To, and give yourself 2 hrs for remove and install, plus time to clean, lube, and rust proof. Beaner7102.