Emergency motor start capacitor

[Audiorepair]

Hi,  a mechanic friend of mine is in trouble, the lift motor start capacitor on his 4 poster car lift needs replacing, and he only has one lift so now cannot work.

The old one is 250vAC, 260uF, which I can't find locally.

He has a 250v 100uF capacitor though.   What would happen if he tried to fit this?  Would it blow up, not work, what?


I know absolutely nothing about motors and start capacitors.

Please help if you can, he has no business right now.

[Berni]

Yep worth a try.

The value is not critical. All that it needs is the phase shift from the capacitor to start the motor into a certain direction. A too small capacitor will simply provide less starting torque.

[Audiorepair]

Thanks for the quick reply, I've let him know.

He's found one on Amazon, so should be fully back up and properly running tomorrow.

[Gyro]

I would be tempted to follow that up with a decent quality brand capacitor from a distributor (at least as a spare).

Amazon aren't renowned for the quality of their capacitors.

[james_s]

I'd expect it will work fine. If you have a critical application like this it's always prudent to keep a spare capacitor on hand. It's a common failure item, I had to replace the capacitor in my mom's heat pump and then in mine a few years later, those usually fail on the hottest day of the year when you really need air conditioning and the repair companies will gouge the hell out of you since they know people who are desperate will pay. It's a $10 part so I always keep a spare on the shelf. Any electric motor shop and many electrical trade counters should have have a suitable replacement in stock.

In some cases, such as the pumps in my hot tub, the capacitors are not starting capacitors but are there for power factor correction.