GTC A/C blower motor

I have a clients GTC we are restoring. As we are assembling the car, all components are restored and run before installation - which leaves me to the AC evaporator box in the car.

Bench testing it after we disassembled it and reassembly - i believe the blower motor has a vibration at high speed that i cannot get rid of. With the vibration obviously more noisy than what i expect, so in the car, i pretty sure i would not like it.

Taking it apart 4-5 times trying to isolate the vibration - im considering to replace the DC blower motor - it has 2 shafts on both ends and the only number on the motor is 5577 FH 12V 235

It measure 2 15/16 diameter, motor housing 3 1/4 and end to end with shafts is 8 inches.

Any thoughts on what and where to get this. I searched all over but not having any idea on the speed of the motor etc, im running into WTF.

Any thoughts - anyone replace one of these?

 

feels smooth with the fans off and on.....however there is a flutter noise at start up and slow down - that i think is coming from the motor itself.

I thought the fan shrouds were causing some oscillation but with everything apart - im leaning toward the motor.

yes each squirrel cage fan has a small clip to balance it - they are in their orig positions and it seems to be ok....

 

OK bob - will check it out

 

thanks for the lead - yes they look similar for sure - will need to get some specs on the size etc to see what could work.

I did order a motor only yesterday in an effort to address the issue, it seems to be a good replacement. I will know later in the week and if it works, ill post some info on the type and style etc. I can see that the SPAL units, the molded duck work might mount slightly different, thus modifications to the existing evap box, but that is not a big deal.

My big issue, is the loud harmonics on high speed that i believe is coming from the motor when all assembled. I really dont want to install this without resolving this issue as doing it later (dash and interior all out of the car now) will be a hugh problem.

Their prices are very reasonable @ 130.00 for a whole unit, motor, cages and housings. I have heard from RPM in vermont where they were making these AC units complete that they are using motors with varying resistance in them to eliminate the resistor rotor switch and just using a 4 position switch which is more available. Sounds like a good improvement etc.

 

thank you steve for the info - sounds like all great upgrades to the system to maximize the AC.

I will investigate the MB motor to understand its design and style.

 

Found a Mack Truck blower motor with dual shafts and about 1/8 difference on the diameter of the motor housing. So a little rubber insulator around the motor housing to mount it did the trick. The oscillation seems to happen when the load of the air flow would occur - thus my decision to replace the motor. This DID fix the problem and now the unit runs smooth with out vibration/oscillation.

With the new 3 speed switch and the rheostat replaced - (also mack tuck parts) im ready to reinstall the AC box. Ill get the numbers of the parts i used for replacement for future reference here on the site - in case

 

part numbers for the motor, rotary switch and rehostate
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Well, here are some thoughts......

1. Condition of the radiator?
2. Voltage on the fan or fans....does it have AC (means u will have two fans) ?
3. Fans turning in the correct direction - to push the air vs pull (lucas motors go both ways) ?
4. Is the fan relay turning on based on the rad temp switch?
5. Solid grounds on all the parts of the cooling system?
6. Rad temp switch on bottom rad working etc?

Bit of a process of elimination....but all critical on the cooling process

 

good point on the water pump......