QL rear lift capacity

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Cyclops1862
Posts: 49
Joined: Thu Mar 03, 2022 8:22 am
First and Last Name: Jay Fetters
Location: Republic Michigan

QL rear lift capacity

Post by Cyclops1862 »

My 1650 has the rear lift. I'm gonna upgrade it to the 3 point kit from Xtreme so I can use a land plane. The Xtreme site says their kit has 35% more lift capacity than stock. Does anybody know what the stock lift is rated at? I asked on another forum, and just got the standard "it'll lift that" answer, but nobody seems to know the actual lift capacity spec. I did receive a good bit of advice from a member, but no spec.
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DaveKamp
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Joined: Mon Sep 06, 2010 10:19 am
First and Last Name: Dave Kamp
Location: LeClaire, Ia

Re: QL rear lift capacity

Post by DaveKamp »

Okay, so...

It is very infrequent that people find the limits of the rear lift...
...because the biggest problem becomes a loss of steering.

The stock lift, though, is a cylinder who's surface is easily calculated, the charge pump pressure is easily measured, and the leverage ratios from rod, through rockshaft, to long bar, to lift arm, isn't hard to calculate... and if I had accurate measurements in front of me, and knew exactly how far out you extended the lift arm, and how far from the transaxle pivot the center of the implement's weight was, I could tell you wether the lift would be strong enough to respond, but there's lots of variables that, until you've got it hitched up, you won't know.

Once you do, you may find that it lifts just fine, but the implement is still on the ground, and the front wheels are in the air.

An average Brinley single-bottom 12 is about 130lbs or so, but that is very subjective, because the center of mass might only be 30" behind the sleeve hitch point. If that 130lbs was 60" behind, the reaction forces would be significantly higher.

Did I answer your question well enough, without answering your question?

Guys are telling you by virtue of 'gut feeling', that it'll lift it... that means, you might hafta put some front weights on, but they're pretty certain it'll play ball.

IIRC the charge pump pressure is about 400psi. There's about 2.5 square inches of piston surface, so rod thrust is ABOUT 1000lbs. My faded memory of it (it was LOONG ago) says the bellcrank leverages are around 1:1, and the final lift rod is about a 2:1 leverage loss, so 500lbs of reaction available at THAT point. Depending on how you have your sleeve hitch set up, it could yield more, or less... but if you're out at twice the distance, you'd be in the 250lb range at most. I'm thinking that would be about the best you could do, before the charge pump's pressure limits out.
Yes, I'm a Mad Scientist... but I'm usually happy, even when things ain't goin right.

Cyclops1862
Posts: 49
Joined: Thu Mar 03, 2022 8:22 am
First and Last Name: Jay Fetters
Location: Republic Michigan

Re: QL rear lift capacity

Post by Cyclops1862 »

I'd say you answered it very well. The loss of steering is the same spec I use on my loboy 185. I have a king kutter disc harrow that I pull with that, and it turns the loboy into a wheelie monster! I fabbed a bracket to 6 suit case weights, and that changed the world!
However, the 1650 is getting a cat0 3 point purchased and installed, and the investment of the land plane. I just wanted to be certain the hydraulics would handle the weight before I dropped over $2k on this project.
And, yes, I know the loboy would pull and lift this implement with ease. The project I am doing, requires the 1650. About 8 years ago I put in over 4 miles of cross country ski trails on our property for my wife and I. They are about 6 foot wide with tight turns that the loboy can't make, but the 1650 negotiates with ease. 3 years ago I graveled all the trails, and this spring, I've noticed the development of some potholes. Which is no good because we jog with our labs on them in the summer. And that, is why I am going through this headache of trying to find lift capacity.
Now, I think I'm convinced enough move forward with calling Xtreme and getting the cat 0 hitch! Thank you!

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Dave C
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Location: Wallingford, CT

Re: QL rear lift capacity

Post by Dave C »

According to this service bulletin. early charge pump pressure was 500 to 625 psi and was increased to 800 to 900psi during the 782 era.

82 SERIES SUNDSTRAND CHANGES SERVICE BULLETIN CC-065

I would have to think a 1650 would fall into the 500 to 625 range, unless they made another change sometime earlier?
But if you needed more pressure you could find a newer pump with the increased pressure, and swap her out.! fun times!
Trying to save cubs... one at a time.......

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SWilliams
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First and Last Name: Steve Williams
Location: Fort Plain NY (Upstate NY near Cooperstown)

Re: QL rear lift capacity

Post by SWilliams »

Not really sure how much is too much, I know my 1641 with the OE rear 3 point would easily lift the front off the ground, even with the blower on it. The hard parts are normally not the stopping point, it's usually the relief valves that dump pressure first. The ASAE rating for a CAT 0 is 450 pounds minimum and I'm pretty sure I've exceeded that a few times. That same part is now on the tail of a 2084 that is being slowly turned into a super super cub. Where I'm trying to add more items than the factory, like 3 lift controls and split hydraulics plus some other items to fix some of the known CC issues.
Owner of an 1863, 2263 (1863 W 22hp engine!) 2084 and a 2 - 2284s.


"In God we trust, All others pay CASH..."

Cyclops1862
Posts: 49
Joined: Thu Mar 03, 2022 8:22 am
First and Last Name: Jay Fetters
Location: Republic Michigan

Re: QL rear lift capacity

Post by Cyclops1862 »

Not sure why it took me so long to see your reply Steve, I check this forum daily! Thank you for the cat 0 spec. I typically use the front wheels are on the ground still spec, but I'm trying to take better care of my tractors these days, as parts aren't getting cheaper, or easier to find.

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