motor to pump couplings

[mga]

what type of coupling do most of you guys use between the engine and your hydraulic pumps on the log splitters?

while splitting some real tuff wood the other day, my lovejoy couplings just chewed each other up. i'm going to replace them, but wondered if there was another option.

 

[rms61moparman]

They are what I use, I've had good luck with mine. Did your center fail?
The centers are pretty inexpensive.
Mike

 

[mga]

the center looked OK. the teeth on the top coupling just all sheared off and the lower one has chips on the teeth.

it's been good for the past two years, split tons of wood....then, it just failed.

 

[rms61moparman]

That almost sounds like the coupling was installed incorrectly. The center must go between the front face of the driving cog and the rear face of the driven cog. Just about had to be in with the metal driving cog against the metal face of the driven cog and the center behind the driving cog.
Is that as confusing as it looks?
Mike

 

[blackdoggy]

I have a 2 inch chunk of round stock thats been drilled and reamed out for my pump to motor connection. I highly doubt if it will ever fail under load

 

[ray benson]

I use couplings like these with an 8 hp motor. Tried several types and with these had the lowest vibrations.
http://www.grainger.com/Grainger/items/1L792
http://www.grainger.com/Grainger/items/1L790

 

[mga]

That almost sounds like the coupling was installed incorrectly. The center must go between the front face of the driving cog and the rear face of the driven cog. Just about had to be in with the metal driving cog against the metal face of the driven cog and the center behind the driving cog.
Is that as confusing as it looks?Mike

lol...nope.

i had them installed like that. the rubber element is still in one piece altho one of the legs is missing, but the engine coupling sheared smooth...all three teeth are gone.

i looked at everything trying to figure out why it happened, but there isn't anything obvious. maybe the rubber spider just broke down and allowed the coupling to spin(?)

 

[redprospector]

I had a pump lock up last winter. I had a 35 horse Briggs pushing it. It pretty much exploded the coupling. I've never had one shear the lug's like you've described without something else being wrong.

Andy

 

[Mike Van]

Lovejoy makes standard & heavy duty couplers, plus spiders of different materials. I'd get the best one you can, being 'broke down' is a pain.

 

[skid row]

Grainger carries three different types of lovejoy spiders. Most couplings have the standard buna-n type rubber. Which works in most cases, and they have a high torque and chemical/oil resistant hytrel spyder insert.

I had to switch to these hytrel inserts on power transmission 3 jaw couplings that were fitted to a single cylinder diesel engine. The power stroke of the diesel was too much for the buna-n type spider and would trash it.

 

[drmiller100]

triple check alignment.

if somnething came loose, or bearing going bad, could explain coupler disintegrating.

 

[mga]

Grainger carries three different types of lovejoy spiders. Most couplings have the standard buna-n type rubber. Which works in most cases, and they have a high torque and chemical/oil resistant hytrel spyder insert.

I had to switch to these hytrel inserts on power transmission 3 jaw couplings that were fitted to a single cylinder diesel engine. The power stroke of the diesel was too much for the buna-n type spider and would trash it.

after removing them, the larger one (1" hole) was an LS-95 while the one on the pump was an INCL-95. the engine one was the one that disintegrated.

here's what i think happened: the rubber spyder partially gave out and the upper coupling was sintered iron while the lower one was cast iron. i believe the cast is stroner than the sintered and that's why the upper one fell apart.

when i replace them, i will get the cast couplings and the hytrel spyder for it.

lesson learned.