Blower Motor and Squirrel Cage

[BruthaMan]

Planning on doing some upgrades this spring (more like next month, here in West/Central Texas!). Spent several hours going through forum posts via google search and while there are number of related posts, I couldn't find concrete information to validate questions.

Blower Motor

Heater only blower motor - no vent tube

AC blower motor - has rubber vent tube

Question: I've come across a number of threads recommending using a mid-late 80s blower motor for more speed/air flow. Has anyone actually done this or have recommendations?

I had it cooling good two summers ago, at the evaporator core, but could never get good air flow (have cleaned out entire system of debris). High speed would yield an airflow barely on par with a modern system on lowest speed.

Squirrel Cage - Blower Motor Wheel

This is where I'm struggling for information.

Question: Is there a difference in the blower motor wheel from Heater only vs AC?

When I pulled mine, a few years ago, it had a plastic wheel that had stripped out such that wheel didn't spin and made a high pitch squeal. I don't recall how, but I managed to convince myself that a metal wheel was in order. I took measurements and did research and found a wheel online. After it arrived, determined it would not mount correctly, so I did some fab work on it to make it fit.

Tonight, I came across this post (scroll towards bottom to see screen shot). Lists a metal wheel.

Question: Is there a difference, performance wise or other, between a metal wheel and a plastic wheel and can anyone provide part numbers to order?

Want to start getting my parts ordered so that when it warms up a little, I can knock everything out in a few days and be ready for the unbearable heat. Appreciate any advice!

Fan/Blower Motor Relay

When I did most of my upgrades a few years ago, I installed a new blower motor relay (behind the glove box). It lasted all of a year, before it went out last summer. No high speed again.

Question: Is it possible to bypass that relay and use a more modern relay solution? For example, something similar to the wiring harness relay for lights? If so, does any have a write up on doing that?

[kamikazekyle05]

I tried using the early 90's blower motor and it wouldn't fit. The squirrel cage was too deep and the blower motor shaft wouldn't accept the old squirrel cage due to shaft length.

[BruthaMan]

Thank you, Kyle.

My wife's family is from Vernon. Appreciate the feedback!

[LockDoc]

Originally Posted by BruthaMan

Planning on doing some upgrades this spring (more like next month, here in West/Central Texas!). Spent several hours going through forum posts via google search and while there are number of related posts, I couldn't find concrete information to validate questions.

Blower Motor

Heater only blower motor - no vent tube

AC blower motor - has rubber vent tube

The vent tube is for cooling purposes and has no bearing on whether a motor will fit your truck or not. My finding is that they will interchange, at least into the early eighties, by changing the squirrel cage.

Question: I've come across a number of threads recommending using a mid-late 80s blower motor for more speed/air flow. Has anyone actually done this or have recommendations?

I'm not sure whether the later ones have more power or speeds or not. I have used a couple from the late '70's- early '80's era trucks and they fit by putting the earlier squirrel cages on them

I had it cooling good two summers ago, at the evaporator core, but could never get good air flow (have cleaned out entire system of debris). High speed would yield an airflow barely on par with a modern system on lowest speed.

The air diverter doors on the A/C units are known for breaking and causing the problem you are having.

Squirrel Cage - Blower Motor Wheel

This is where I'm struggling for information.

Question: Is there a difference in the blower motor wheel from Heater only vs AC?

I don't think so but I can check tomorrow. I think all of the '67-'72 wheels are the same.

When I pulled mine, a few years ago, it had a plastic wheel that had stripped out such that wheel didn't spin and made a high pitch squeal. I don't recall how, but I managed to convince myself that a metal wheel was in order. I took measurements and did research and found a wheel online. After it arrived, determined it would not mount correctly, so I did some fab work on it to make it fit.

I have parted some trucks with the metal wheel cages but I think they were probably replacement units. I always save them because they are mouse proof.

Tonight, I came across this post (scroll towards bottom to see screen shot). Lists a metal wheel.

Question: Is there a difference, performance wise or other, between a metal wheel and a plastic wheel and can anyone provide part numbers to order?

I don't think one is any better than the other except for the resistance to mice chewing through them as stated above.

Want to start getting my parts ordered so that when it warms up a little, I can knock everything out in a few days and be ready for the unbearable heat. Appreciate any advice!

Fan/Blower Motor Relay

When I did most of my upgrades a few years ago, I installed a new blower motor relay (behind the glove box). It lasted all of a year, before it went out last summer. No high speed again.

Question: Is it possible to bypass that relay and use a more modern relay solution? For example, something similar to the wiring harness relay for lights? If so, does any have a write up on doing that?

I can't help you with this part but I would find a good original before I would use an aftermarket relay. ....

LockDoc

[BruthaMan]

Excellent information, Leon! Your advice is very much appreciated!

[1972BlueC20]

I bought a new blower motor and metal fan from classicparts.com

It was cheap and blows awesome!!

[FirstOwner69]

Here are links to two recent discussions. One deals with blower motors. The other deals with squirrel cages. Don't know if you saw them.
http://67-72chevytrucks.com/vboard/s...d.php?t=643469
http://67-72chevytrucks.com/vboard/s...d.php?t=642884

My 69 with A/C came new with a metal cage as I noted in one of the above linked threads.

If you look up blower motors for your truck on Rock Auto's website then click on the part number, you'll get a list of all the vehicles the motor will fit. For example, they say the motor they sell will fit 1955-1990 "Chevrolets" but only 1964-1987 GMCs. Based on that, I'd guess it may only fit 1962-1987 Chevrolet trucks but also other years in other Chevy models. This seems to substantiate comments made by other posters. The motor they sell has the ventilation hole. If you don't have A/C you would likely want to plug the hole.