Treadmill Repair help Needed

[gaja]

Hi,

I bought a treadmill recently from ebay and it came with a problem that I'm trying to fix but am stuck.

The treadmill has manually operated variable speed and at low speed with no one walking on the treadmill belt it works ok.

Add someone to the belt at low speed and it works ok too. Increase the speed a little or add someone heavier than me and the motor stops then runs slow with next to no torque.

Turn the power off, leave it a while and it's ok again.

I took the cover off to see a 2 hp motor and a control board. Running the test above again with the cover off I noticed an LED on the board light up when I turn the speed up or apply wieght. The LED is marked "CUR LIM" which google tells me stands for current limiter which is apparently a circuit designed to prevent escessive current being drawn. My question is what is causing this. Is the motor worn and trying to draw too much current hence the limiter kicking in or is it another problem? The treadmill is quite old so motor wear would not be a surprise.

Any help gratefully received.

Thanks

 

[KeepItSimpleStupid]

Look for areas of friction in the entire mechanism from motor bearings etc. Spend time cleaning/lubercating the bearings.

 

[tunedwolf]

Early machines used a dedicated controller board for the deck motor, later ones use a programmed inverter. Sometimes the inverter back up battery gives up and the programming of the inverter is lost and returns to default values for acceleration, motor current etc. Deck rollers are a possibility if it's an old machine, the bearings are replaceable, however they are usually a press fit to the shaft which will make it awkward to do at home. It's usually dead obvious if they are shot, it will rumble like mad and the shaft will bind when turned by hand. The other possibility might be that the deck is dry. Most machines use a phenolic type deck and require a little lube now and then to stop the track binding. This isn't just normal oil, get the right stuff. If you disturb the deck rollers, be sure to mark the distance from the frame that each tensioner is set at, otherwise the track will run off to the side and foul the frame, the rollers must be parallel to each other for the track to run true in the centre of the deck.
Hope this gives you a couple of ideas...

rgds

 

[johnsmith123]

Look for areas of friction in the entire mechanism from motor bearings etc. Spend time cleaning/lubercating the bearings.

Check the track.

If the track is not aligned, you can adjust the track. The treadmills I have seen have a bolt to tighten on each side at the end of the belt. Whilt running the treadmill at low speed, tighten the side that is furthest away from the bolt you are accessing keeping the track centered. You will see that the track moves toward the bolt you are tightening.

Now it is possible that the track is too tight. In this case run the treadmill and loosen both sides a little bit each time keeping the track straight (track is centered) when spinning.

This is the same technique used to adjust a snowmobile track.

 

[HiTech]

A good many treadmills come with a small vial of tread belt oil. Yours may be in need ot lubing the underside of the belt to reduce friction. As mentioned, check for proper belt tension by adjusting the rear spindle the belt rotates on. A nicely waxed hardboard also helps with easing tread belt friction and drag.