Adding oil to draft inducer/booster motor

[msufroggy]

I have a few questions re: the draft inducer/booster motor, so I thought I would combine them all in one post (hope everyone doesn't mind).

I have a Coleman presidential II model, and the motor p/n is 770-8314 (the approx 8 inch cylindrical black motor).


1) Before I call a repair man out, I wanted to try to oil the draft/booster motor first to see if that helps. The furnace was fairly dusty and I just finished vacuuming and dusting it out.

I see 2 metal "spout type" projections coming from the motor, and the bottom spout is titled "oil".
So what type of oil do I use, and how much do I put in there?


2) Also, I read in the quick tech tip guide how to "hand spin" the draft inducer/booster motor first to see if it "sticking" was the problem. How do I hand spin the motor? Do I just turn the metal rod coming out from it?

3) I looked at the parts prices on this website. I notice there is a booster motor with and without the assembly. How would you know if you need the entire assembly, vs just getting the motor w/switch?


Any info would be greatly appreciated. I really think the problem is either with the motor and/or the switch inside (since I believe my father, who is licensed HVAC, before he passed said the motor is going out when this happened to my furnace a couple of years ago.

Thanks!
Heather

BTW, this website has been a Godsend! I, as I am sure others too, thank you sooo much for all the advice!

[Robert]

Hi Heather,

What is your furnace model number ?

You're very welcome, happy to help.



Thanks,
Robert

[msufroggy]

Oops sorry..meant to post that...

Model: 7710-856

Serial: 068360305

It's a 95,000BTU input, 70,000BTU output.

[Robert]

Hi Heather,


1.- Oil with SAE 20 oil every 6 months. Look on the motor label and see if it says how much.

Usually 2 to 6 drops each oil spout, so if it doesn't say, try 2 drops each for now.

Oil it and let sit for an hour or two before doing next step.


2.- You spin the motor wheel (squirrel cage) inside metal can above motor that sits on the shaft of motor.


3.- If wheel spins ok, then motor would be all that would possibly be needed.


If removing wheel housing, do it very gently to not damage gasket around edges too bad.


Also, trace the motor wires back to connection and ensure you are sending 120vac to motor.


Trace the two centrifugal switch wires back and ensure you have 24vac for it.


Normal wiring colors would be Blue for cent. switch 24vac and Black for booster motor 120vac.



Take care and best wishes,
Robert

[msufroggy]

Thanks a bunch!!!

[Robert]

Hi Heather,

You're very welcome, happy to help.



Take care and best wishes,
Robert

[msufroggy]

Sorry, another question.

Where would I find SAE 20 oil?

[Robert]

Hi,

Hardware store, big box stores, home centers, etc... .



Take care and best wishes,
Robert