Hewitt boat lift making loud bangs

[green head]

I have a Hewitt vertical lift 3800 pound. I keep a 20 foot Bennington lift on it, it weights approx. 2200 lbs. When I lower it there are loud single bang sounds coming from the gear box every few rotations of the manual wheel. Once the toons start hitting the water and the weight transfers the bangs stop. No bangs on the crank up. What is going on?

 

[Grub54891]

I'd guess one of the gears are going bad, also a bearing will sometimes make noises in one direction but not the other when its starting to go bad.

 

[ahicks]

My bet would be the cable is wound on the spool sloppy and the bang you're hearing is it coming untangled, rather than coming off the spool smoothly.

I would pull the cover off so you can see what's going on, and if you have to, pull all or most of the cable off the winch drum and rewind neatly - with gloves on! Be careful of that cable on your hands!

 

[green head]

Sorry for the long delay. I got busy with other stuff. The lift is out of the water now but I watched the cable coming off and it looked to be fairly organized. When the bangs happened it looked like the chain/gears were slipping or surging just the smallest amount. Is there anyway to test if the gears or bearings are bad? Or just replace and see if happens again next year.

 

[Grub54891]

Sorry for the long delay. I got busy with other stuff. The lift is out of the water now but I watched the cable coming off and it looked to be fairly organized. When the bangs happened it looked like the chain/gears were slipping or surging just the smallest amount. Is there anyway to test if the gears or bearings are bad? Or just replace and see if happens again next year.

You would have to inspect each bearing, all the chains and sprockets. Look for loose bearings, set screws that are loose, stiff chains. With it out of the water, you can lower it enough to get all the working mechanisms loose and get in there and wiggle each part.

 

[Old Ironmaker]

Good advice above. The bang is a result of a major portion or the entire wieght of the boat bearing down on metal on metal inside the mechanics of the gear box, skipping. The kogs may look fine during inspection, I doubt that, there may be a portion of a tooth broken off. Look for skuff marks on your gears that may be the result of the big bang. Replacing 1 bad actor may not be doable, how old is the thing? Inspection is a must, I wouldn't think it would be huge endevour. I would not swap out the gear box without knowing the root cause. The "bang" may still be there next year after changing the gear box.

 

[Scott Danforth]

bang = bad
bad = dropping the boat and potential injury

so find what the problem is and fix it BEFORE you use the lift again.

 

[ahicks]

If the cable is winding and unwinding evenly, it's most likely something, somewhere, is sticking, and not working as smoothly as it's supposed to. Any lift I've ever worked on is a pretty simple affair. Actually, REALLY simple! Absolutely no rocket science involved or required to fix!

They are chain driven for the most part. If that chain is all dried out and rusty I suppose it could be making some noise or causing a jerky action as it goes over the gears. The pulleys that the cables run on that haven't been maintained could be trying to freeze on the shafts and causing some issues there as well.

The hardest part of this project will getting started on it. Once you dive in and get your hands dirty, I'll be surprised if the issue takes much to find. Start by making sure all moving parts are well lubricated and working smoothly.

 

[green head]

I found a bushing on the upper gear that was almost worn through. I am going to replace it and maybe that was the problem. I disassembled the whole gear box and didn't see anything else. I took the time to clean and put fresh grease where required. I looked over all the pulleys on the lift itself and they looked good too.

 

[ahicks]

Sounds like you found your problem to me. I've never seen one worn that bad.

 

[Brian8848]

I found a bushing on the upper gear that was almost worn through. I am going to replace it and maybe that was the problem. I disassembled the whole gear box and didn't see anything else. I took the time to clean and put fresh grease where required. I looked over all the pulleys on the lift itself and they looked good too.

I am having the same banging noise...it started when going down only but now is happening in both directions. Did this fix your issue? Tough to diagnose and fix? Thanks in advance!