Log Splitter Coupler Keeps Dropping

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Cambium

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Hi guys.. After troubleshooting for the non working Cylinder rod I found out it was broken teeth on the couplers. Ouch. 1st pic.

Ordered the 3 parts from manufactuer. $35 total. Put everything back together, everything worked. After 5 minutes the Pump coupler dropped back down. I loosened the set screw, pushed it back up and lined up the couplers, tightened the set screw good. Split wood for 45 minutes. Fine.

This morning, I go to start splitting and the bottom coupler dropped again. (2nd pic)

My pump coupler keeps dropping down even after tightening the set screw.

Does the motor coupler need to be lower?

What else could be issue? I did lube the shaft which I'm hoping is not the reason. Maybe its too greased up and the coupler keeps dropping?

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Decided to drop the pump coupler all the way down and tighten everything back up. Kinda worried if the motor coupler had enough shaft to support it. Everything seems fine now. We'll see. I'll update if anything goes wrong.

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Lot of folks need 'couples' therapy around this time of the year . . .just 'sayin . . .

LOL. Yes, sign me up! lol.

Funny. Here is another thread about couplers.

I didn't want to hi-jack that thread so I will continue here. If this thread is in the wrong forum please move it.

Apparently they split apart again. The spider chipped just a little but 95% still good. So I learned from the other thread there needs to be a gap between couplers.

But how about the distance from the Pump base and the engine mount?

Do I go lower or higher with which coupler?

Do the shafts have to touch or come close??

I will push them together more but wondering about the other things before I put back together.

Thanks!


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I noticed I got a better alignment when I put back the engine. The coupler fell into place instead of me needing to force it in. That smoothness told me it was aligned better. So is this an ok gap?

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Does the set screw land on the shaft key? You may have to improve the interference fit of the key in the key way.

Yes, I made sure the shaft key lined up. The coupler basically doesn't slide on unless its lined up. But now that you mentioned it I may have to check the "interference" with the other coupler. Still a rookie at all this. But otherwise I'll fire it up in the morning assuming all gaps are fine.

I also wasn't sure how high up or down the shaft the coupler needs to go.
 
I'd think the bottom coupler should be set so with the key bottomed out in the key way the set screw still has 100% contact. If the key isn't bottomed out you're tightening your set screw against an object that can and will slide down.

Another trick we used to use is to get everything lined up, then tighten down the set screw. Take everything back apart and drill a very shallow hole in the key where the set screw mark was for the set screw to seat in when it is put back together.
 
A little after the fact but check the tip of the set screw. It should have little teeth to dig into the shaft or key to Keep it from backing out. If they are worn off maybe that's why its backing out. Also a dab of blue loctite couldn't hurt either.
 
This may or may not be helpful but I will offer advice anyway. I am a hydraulic tech at dalton hydraulics. The most common cause of coupler failure and vibration is shaft misalignment. If you haven't, you might want to check that.
 
Howdy,

I see this is dated but, this might help somebody in the future.

Every once in a while you'll run into a tough one. I've had good luck with using a piece of PVC pipe slit down the side, along with a few hose clamps. Then tighten the engine and pump mounting bolts.

Regards
Gregg
 
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