Two Speed Fan Inoperative - Page 3

T-Cut · 24th July 2015, 17:01

Quote:

Originally Posted by STUBIE

Motor burned out due to possibly Gold resistor failure.

Failure of a gold or silver resistor won't burn out the fan motor. Resistors blow all the time, but it would need something more serious to burn out the fan motor. Do you mean possible failure through brush wear? It could happen if the high speed was forever on through relay points fusion for example. Or the fan blades being fouled for some reason. As you note, 2-speed motor failure is rather rare.

TC

werdna232002 · 25th July 2015, 09:24

You can either replace the resistor and brushes from the old fan motor as most certainly the slow speed brushes is already past its life. Or replace the whole unit with new revotec one from jules. If you need help fixing it you can come down to middlesex and ill help you.

RayH · 25th July 2015, 09:43

Quote:

Originally Posted by werdna232002

You can either replace the resistor and brushes from the old fan motor as most certainly the slow speed brushes is already past its life. Or replace the whole unit with new revotec one from jules. If you need help fixing it you can come down to middlesex and ill help you.

I'm not sure what you mean by "slow speed brushes"
On a two speed there are no different brushes, as the speed difference is achieved by the resistor.

werdna232002 · 26th July 2015, 10:35

Quote:

Originally Posted by RayH

I'm not sure what you mean by "slow speed brushes"
On a two speed there are no different brushes, as the speed difference is achieved by the resistor.

My mistake, I should have said "all brushes". I had the two three speed fan which had no resistor.

RayH · 26th July 2015, 10:56

Quote:

Originally Posted by werdna232002

My mistake, I should have said "all brushes". I had the two three speed fan which had no resistor.

Phew! That's okay then, I thought there was yet another variation

Thanks for clarifying that.
Generally to brushes on the two wire motors seem less prone to trouble though, but ultimately they will wear out and they are all getting older.

Jules · 26th July 2015, 23:03

The rear bearings tend to fail first on the later 2 speed motors.
(especially if they are sat next to very hot running tired and corroded condenser)

Usually good for 150k miles or so

Jules · 30th July 2015, 23:12

Quote:

Originally Posted by T-Cut

Failure of a gold or silver resistor won't burn out the fan motor. Resistors blow all the time, but it would need something more serious to burn out the fan motor.

TC

In a roundabout way it can TC
Scanario
Resistor fails (owner unaware)
Fan pulses on & off high speed with 65 amp surges going through a 40 amp relay.
Eventually the relay welds itself together and the fan wears itself out on prolonged high speed, if the owner persists in driving like that !! (seen a few)

26th July 2015, 23:03	#26
Jules This is my second home ZT 260 SE Twilight and 10 other 75 ZT's :O Join Date: Jan 2007 Location: Conwy NORTH WALES Posts: 11,094 Thanks: 512 Thanked 1,116 Times in 763 Posts	The rear bearings tend to fail first on the later 2 speed motors. (especially if they are sat next to very hot running tired and corroded condenser) Usually good for 150k miles or so __________________ [SIGPIC][/SIGPIC] Newbies do now!! 1. Plenum drains..all 3 or 4 year dependent 2. Cooling fan..All speeds functioning 3. Bonnet cable divider block

25th July 2015, 09:24	#22
werdna232002 Avid contributor ZTT 2.0 cdti 135 Join Date: Apr 2015 Location: Isleworth, Middlesex Posts: 189 Thanks: 14 Thanked 32 Times in 22 Posts	You can either replace the resistor and brushes from the old fan motor as most certainly the slow speed brushes is already past its life. Or replace the whole unit with new revotec one from jules. If you need help fixing it you can come down to middlesex and ill help you.