Car lift problem

[leveled]

I Went to a different electric motor shop today, I had them test the capacitor again, it tested fine. The owner spent some good time with me, and he suggested that it is most likely a hydro problem. Bendpak has sucked through out this process. I am going to call them again because they have not gave me any clue or even a local service company to contact for service.

 

[leveled]

Is there a check valve on the base of the cylinder as well as one on the pump? If so, would suspect that the check valve on the cylinder is leaking by and putting pressure on the pump check valve.

Aaron Z

I am going to check this now, it would make sense that it would be set up like that.

 

[BertZegers]

I am going to check this now, it would make sense that it would be set up like that.

If it had a check valve on the cylinder it could only extend and not retract.

Please post motor-plate picture or at least the FLA of the motor. We know from your posts that the running amps are 11 or 12 Amps. When we know the motor plate info we can determine if there is a overload on the output shaft of the motor.

 

[leveled]

If it had a check valve on the cylinder it could only extend and not retract.

Please post motor-plate picture or at least the FLA of the motor. We know from your posts that the running amps are 11 or 12 Amps. When we know the motor plate info we can determine if there is a overload on the output shaft of the motor.

They must have used bad ink because the data is not there. Its has nothing on it.

 

[leveled]

I took off the line and blew air through it, it seems fine. I maxed the lift out and it runs through the pressure relief valve. I did not see a check valve on cylinder, I even looked to see if it was on the other side on the 90 fitting.

 

[flyerdan]

It seems like it would need some kind of unloader valve to allow the motor to start before encountering the full load. It should work the same way as a tilt trailer, the principle is the same; they will start again after a partial raise.

 

[ovrszd]

I am going to check this now, it would make sense that it would be set up like that.

If there was a check valve at the cylinder how would you ever be able to lower the lift?

 

[ovrszd]

Sorry, I should have read down...

 

[BertZegers]

They must have used bad ink because the data is not there. Its has nothing on it.

OK, The Bendpak website lists 1.5 and 2.5 HP motors for 4 post lifts.
a 1.5 motor would have a FLA of 7 amps more or less.
a 2.5 motor would have a FLA of 12 amps more or less, but the 12 amps would be correct for a maximum loaded lift. Empty, the lift should draw considerably less!
It looks like the motor has to work its maximum capacity to lift an empty platform.

I would suggest that you lift the platform to 5 feet, make sure the platform is safety locked, take the hydraulic hose of the cylinder and put the hose in a container. Than start the pump and check if there is full flow. The motor/pump should run very easy.

If you have a full steady flow, than that would narrow the problem down to the cylinder or mechanical.

 

[ovrszd]

Were it me,,,,,, I'd call my Sons and friends to come over and group analyze my lift.....

I think you are so deep into it now that you wouldn't see the problem if it presented itself. I hate it when that happens. Been there many times.

Do you have a circle of friends/family that you could get involved in this problem?