I've seen a number of older exhaust fans that start very slowly. Turn them on,
they barely turn for up to several minutes, then finally speed up fairly quickly
to normal operating speed. Can anyone suggest why this happens, and a way to fix
them to operate properly?

Bob F wrote:
I've seen a number of older exhaust fans that start very slowly. Turn them on,
they barely turn for up to several minutes, then finally speed up fairly quickly
to normal operating speed. Can anyone suggest why this happens, and a way to fix
them to operate properly?



First thing to try is lubing the bearings I would think

Rheilly P

On Sep 5, 4:10*am, Rheilly Phoull wrote:
Bob F wrote:
I've seen a number of older exhaust fans that start very slowly. Turn them on,
they barely turn for up to several minutes, then finally speed up fairly quickly
to normal operating speed. Can anyone suggest why this happens, and a way to fix
them to operate properly?

First thing to try is lubing the bearings I would think

Rheilly P

If you are talking about the roof attic fans, the motor might be
starting to go. They sell replacement motors at Lowes or HD and they
are easy to change.

Mikepier wrote:
On Sep 5, 4:10 am, Rheilly Phoull wrote:
Bob F wrote:
I've seen a number of older exhaust fans that start very slowly. Turn them on,
they barely turn for up to several minutes, then finally speed up fairly quickly
to normal operating speed. Can anyone suggest why this happens, and a way to fix
them to operate properly?
First thing to try is lubing the bearings I would think

Rheilly P

If you are talking about the roof attic fans, the motor might be
starting to go. They sell replacement motors at Lowes or HD and they
are easy to change.
Sure, that will fix it but having spent a large part of my work life
sorting that sorta stuff I can tell you a lot of the time the motor runs
away with no attention until it stops or exhibits the symptoms described.
The manufacturers provide ports to apply periodic lubrication which are
by and large ignored by the average punter. A slow start is almost
certain to be an underlubricated bearing or one that has been worn out
by long usage or underlubrication, usually both.
Nowadays the cost of professional maintenance can exceed the cost of a
replacement (assuming you DIY) so there ya go. For me there is nothing
to lose with trying a squirt of light oil on the bearings before
spending ya moola :-)

Cheers ............ Rheilly P

In article , Rheilly Phoull wrote:
Bob F wrote:
I've seen a number of older exhaust fans that start very slowly. Turn them
on,
they barely turn for up to several minutes, then finally speed up fairly
quickly
to normal operating speed. Can anyone suggest why this happens, and a way to
fix
them to operate properly?



First thing to try is lubing the bearings I would think

Nope, that's the second thing. First thing is to check for two decades' worth
of dirt and crud built up on the blades, and clean as necessary.

"Bob F" wrote in message
. ..
I've seen a number of older exhaust fans that start very slowly. Turn them
on, they barely turn for up to several minutes, then finally speed up
fairly quickly to normal operating speed. Can anyone suggest why this
happens, and a way to fix them to operate properly?


I've seen this a number of times with bathroom exhaust fans. After removing
the internal parts and cleaning them thoroughly, performance on many of them
improves. Gunk tends to build up on the fan blade which I surmise causes it
to be heavier than the little motor was designed for. If not then I replace
the motor and blade or install a new and improved (Panasonic) bath fan.

"Bob F" wrote in message
. ..
I've seen a number of older exhaust fans that start very slowly. Turn them
on, they barely turn for up to several minutes, then finally speed up
fairly quickly to normal operating speed. Can anyone suggest why this
happens, and a way to fix them to operate properly?


I assume you are talking about the motors without a capacitor and a start
terminal. These motors develop weak torque until reaching full speed. The
lubrication gums and the motor spins slow for awhile. It is best to
dissasemble the motor, degrease the bearings and apply a light oil (like 3
and 1 motor oil).

Cause they're gummed up with ****. Need to disassemble them, clean them
with brake cleaner, and relube the end bushings.


s


"Bob F" wrote in message
. ..
I've seen a number of older exhaust fans that start very slowly. Turn them
on, they barely turn for up to several minutes, then finally speed up
fairly quickly to normal operating speed. Can anyone suggest why this
happens, and a way to fix them to operate properly?

The folks I have worked with tell me that three in one is a poor choice for
motors. It (three in one) dries out rapidly. Same with WD-40. The good
choice is ND-30 motor oil, or zoom spout turbine oil. The gas mix oil for
two strokes is supposed to be good, also.

Cleaning the blade sounds like a wise action, also.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"JohnR66" wrote in message
...

The
lubrication gums and the motor spins slow for awhile. It is best to
dissasemble the motor, degrease the bearings and apply a light oil (like 3
and 1 motor oil).

On 9/5/2008 4:03 AM Rheilly Phoull spake thus:

Mikepier wrote:

On Sep 5, 4:10 am, Rheilly Phoull wrote:

Bob F wrote:

I've seen a number of older exhaust fans that start very slowly. Turn them on,
they barely turn for up to several minutes, then finally speed up fairly quickly
to normal operating speed. Can anyone suggest why this happens, and a way to fix
them to operate properly?

First thing to try is lubing the bearings I would think

If you are talking about the roof attic fans, the motor might be
starting to go. They sell replacement motors at Lowes or HD and they
are easy to change.

Sure, that will fix it but having spent a large part of my work life
sorting that sorta stuff I can tell you a lot of the time the motor runs
away with no attention until it stops or exhibits the symptoms described.
The manufacturers provide ports to apply periodic lubrication which are
by and large ignored by the average punter. A slow start is almost
certain to be an underlubricated bearing or one that has been worn out
by long usage or underlubrication, usually both.
Nowadays the cost of professional maintenance can exceed the cost of a
replacement (assuming you DIY) so there ya go. For me there is nothing
to lose with trying a squirt of light oil on the bearings before
spending ya moola :-)

True that.

To which I would add two things: 1) Most motors will last forever if
maintained. They rarely "burn out", but simply get gunked-up bearings.

2) If squirting some oil into the bearing cups doesn't do the trick,
then it's time to take the motor apart, clean and lube everything, and
put it back together. Helped a friend do that to an exhaust-fan motor
that was thickly coated with cooking grease and just sat there and
hummed. We knocked it apart (had to use a cold chisel around the cover
seam), whereupon one of the armature wires broke off. No problemo: a
little soldering-iron action plus some heat-shrink insulation fixed
that. Soaked the bearings in paint thinner, cleaned them, lubed and put
together. Now it works like new.


--
Washing one's hands of the conflict between the powerful and the
powerless means to side with the powerful, not to be neutral.

- Paulo Freire

"David Nebenzahl" wrote in message
s.com...
On 9/5/2008 4:03 AM Rheilly Phoull spake thus:

Mikepier wrote:

On Sep 5, 4:10 am, Rheilly Phoull wrote:

Bob F wrote:

I've seen a number of older exhaust fans that start very slowly. Turn them
on,
they barely turn for up to several minutes, then finally speed up fairly
quickly
to normal operating speed. Can anyone suggest why this happens, and a way
to fix
them to operate properly?

First thing to try is lubing the bearings I would think

If you are talking about the roof attic fans, the motor might be
starting to go. They sell replacement motors at Lowes or HD and they
are easy to change.

Sure, that will fix it but having spent a large part of my work life sorting
that sorta stuff I can tell you a lot of the time the motor runs away with no
attention until it stops or exhibits the symptoms described.
The manufacturers provide ports to apply periodic lubrication which are by
and large ignored by the average punter. A slow start is almost certain to be
an underlubricated bearing or one that has been worn out by long usage or
underlubrication, usually both.
Nowadays the cost of professional maintenance can exceed the cost of a
replacement (assuming you DIY) so there ya go. For me there is nothing to
lose with trying a squirt of light oil on the bearings before spending ya
moola :-)

True that.

To which I would add two things: 1) Most motors will last forever if
maintained. They rarely "burn out", but simply get gunked-up bearings.

2) If squirting some oil into the bearing cups doesn't do the trick, then it's
time to take the motor apart, clean and lube everything, and put it back
together. Helped a friend do that to an exhaust-fan motor that was thickly
coated with cooking grease and just sat there and hummed. We knocked it apart
(had to use a cold chisel around the cover seam), whereupon one of the
armature wires broke off. No problemo: a little soldering-iron action plus
some heat-shrink insulation fixed that. Soaked the bearings in paint thinner,
cleaned them, lubed and put together. Now it works like new.


--

I seem to have another project to do. Thanks everyone for the feedback.