cecilelegare

Hi,
sorry for my english... I'll do my best to explain my problem : this morning, before I started my 1989 Chevy Van 20 (5.7l, V8) I set my heating levers on "Economy heat"+"low" fan and I chose a middle position for temperature. Then I started the engine and a burning smell and a white smoke came right away from the middle front vents. I turned off, checked under the hood but there was no smoke nor smell. I started again the van (without heat) to park it back, there was no problem for the engine. I booked an appointment with the mechanic but he can't check it before end of may...
Do you know if it sounds bad (and expensive repairs) and could you tell me if I can use my van without using the heat of course until the garage appointment ?
Thank you !

canucklehead

Could it have been a white dust instead of smoke? The smell could be the heater motor going....does it still work?

cecilelegare

Thanks,
but unfortunately it really smelled like burn. And it still smells burned inside the van. I didn't try again to turn on the heater again, I'm scared to do more damages because I know nothing...

canucklehead

The heater motor is probably shot. Tough to repair if you are not handy.

cecilelegare

It sounds like you are right...and I'm not handy even with the repair book I have so let's go to a professional
and thank you again for your reply

canucklehead

While it is apart, you may want to do the heater core at the same time....

cecilelegare

thanks for the advice, sounds like it will be really tough, oh my...
I noticed that the coolant level is enough but low. Is it linked to the problem, can it have been a trigger ? And it was the first time since last fall that I used the heater. The van spend the winter outside in the yard and we had pretty low temperatures (average of -15 C).

canucklehead

Coolant level might not be an accurate way of seeing if there is a leak. You can have it pressure tested, but if the heater core was leaking you should see evidence of it in the cab, and or condensation/steam on the inside of the windshield.

CNG Pete

Previous experience has been corroded/poor connections on the heater fan switch. After getting access to the switch you will see the connector or wires melted.

I have never had a blower motor fail with a burned smell.

-Pete

mp2140

Your problem may well be the blower motor, but one part you might want to check is the resistor module that varies the speed of the blower motor. It's a small part located in the main air duct by the fan. It has several spring shaped wires on it that provide resistance so the blower motor can run slower. It's an easy problem to troubleshoot, when you start up the van turn on the heater and slowly run your fan speed control lever through each spot. Does it run on some speeds and not on others? If that's the case, then it's probably the resistor module. On some older GM vans, '73-'95, the resistor module is accessible through the engine compartment through the hood. On the newer Express and Savana models, it's under the hood as well on the left upper side, the blower box protrudes from the firewall and the resistor / relay is on top. Not too bad to replace. I've burned up the resistor modules before, sometimes they stop working with no smoke, sometimes there's smoke and an odor. I have had a blower motor go out on an older model Chevy van. I replaced it then tore the old one apart to see what the insides looked like. The motor brushes were completely wore out and only the springs were making contact with the armature. So it is possible that it's the electric motor. Good luck finding the issue, I do think your problem is solvable. Let us know how it goes.