Bent Piston / Cylinder - Need some advice

[woodlandfarms]

On my FEL, the tilt cylinder rod is bent. I think it was this way when I bought it. This all said, I am thinking of increasing my lift capacity. So, can someone tell me how these pistons work in relation to getting a stronger one? I think they are 20" or so (I am not with the tractor this week so these are estimates). I think the road is 1" thick.

So, am I assume that I am looking for a cylinder that is 1.5" (the diameter of the rod is proportional to the lift strength?) or is there something else I should be looking for.

I am not sure I am going to do this upgrade, I am fully aware of the potential over stress complications and want to do some more research before I do this.

That said, if someone can edumacate me that would be cool.

Carl

 

[Mith]

The strength of the lift relies on the diameter of the bore of the cylinder. Bigger bore means more power.
Usually a larger rod means a larger bore, but not necessarily.
Measure the diameter of the casing of the ram, and get a ram with a bigger outer casing, this will mean the bore is bigger.
Rams are usually sold by the bore size anyway.

There is alot of work involved in upgrading the cylinder size, you'll probably have to change most of the mounting brackets for the clyinders, as well as beef up the frame.
For a quick lift power boost you could increase the hydraulic pressure, but this will provide other complications.

Cheapest option would probably be to have a new rod made to replace the bent one.

 

[zzvyb6]

What about straightening the bent rod? I presume its not kinked. Pull it all the way out and apply some force by driving over it with the tire of a car or truck. This will apply a smooth, uniform load without scratching it. If you replace the cylinder with anoher of a different size, you willl need to replace both if there is one on each side. I had a snow plow cylinder bend/bow and this technique worked beautifully. Put it in some sand and drive on it.

 

[Kernopelli]

I would suggest removing the rod from the cylinder (very easy task) and using a hydraulic press to carefully straighten it. A dial gauge would be handy to check it for trueness and where to apply pressure as you straighten it but rolling it on a very flat surface or using a good straight edge will get you pretty close.

 

[cp1969]

On my FEL, the tilt cylinder rod is bent. I think it was this way when I bought it. This all said, I am thinking of increasing my lift capacity. So, can someone tell me how these pistons work in relation to getting a stronger one? I think they are 20" or so (I am not with the tractor this week so these are estimates). I think the road is 1" thick.

So, am I assume that I am looking for a cylinder that is 1.5" (the diameter of the rod is proportional to the lift strength?) or is there something else I should be looking for.

I am not sure I am going to do this upgrade, I am fully aware of the potential over stress complications and want to do some more research before I do this.

That said, if someone can edumacate me that would be cool.

Carl

For a given cylinder diameter, the larger the rod, the weaker the cylinder will be on the return stroke. There is a lot of thought that goes into sizing both the inside diameter of the cylinder and the size of the rod.

If you think it may have been like this when you bought it, it could be from the previous owner grossly over stressing it. If that is the case, you could probably just repair it and be done with it unless you are going to overstress it, too.

If you beef up the cylinder, you may cause the weak point to show up somewhere else that is NOT so easy to repair.

 

[sandman2234]

I think I would pass on driving over it with a vehicle. Too many varibles, to much chance of overbending/underbending and having to keep making corrections which require continually stressing the shaft.
The press might work provided you have a way to keep the rod from rotating while being deflected.
I always think of a cylinder rod as an overgrown nail. The top of the nail where the hammer hits is surface where the hydraulic fluid pushes on to extend the shaft. The smaller surface under the head of the nail, around the shank is where it pushes to retract it. If the diameter of the nail increases without the size of the head increasing, you loose some of the retracting capacity. If you increase the head size (bore of the cylinder) then you increase both, but if the rod also increases in size, it is a proportional gain.
I think I would straighten it/have it straightened and then go from there. If you are seriously considering an increase in size, then try not to go overboard with it. Even a 1/4" diameter increase in bore should increase the load lifting ability considerably.
David from jax

 

[scott_vt]

I would suggest removing the rod from the cylinder (very easy task) and using a hydraulic press to carefully straighten it. A dial gauge would be handy to check it for trueness and where to apply pressure as you straighten it but rolling it on a very flat surface or using a good straight edge will get you pretty close.

Mornin Carl,
Im with Darryl on this one ! A press is the best way to straighten out your bent cylinder, under a controlled enviroment, using a dial indicator for your best chance of success ! My neighbor has successfully used his log splitter to do this but thats a crap shoot IMO ! Good luck !

 

[john_bud]

If the rod bent in use, the use is too tough for the rod. (well, duh!)

Here is how curl cylinders work in a nut shell. The area of the cylinder bore is multiplied by the PSI of the hydraulic system. That number is the pounds of push force. The area of the cylinder MINUS the area of the rod times the PSI is the pull force.

The strength of the rod to resist bending is determined by the thickness of the rod and the length (torque felt).

If you just increase the diameter of the rod (and gland, seals, wipers etc) the curl power of the bucket will be reduced. Curl is done by retracting or pulling the bucket. You need to determine the bore and rod diameters and increase both by 1/4" to 1/2". Common cylinders have bores that jump in 1/2" increments. Rod's jump by 1/4's commonly.

You need to measure the following items to fully spec a replacement cylinder.

1) Bore
2) Rod diameter
3) Closed or minimum length (pin center to pin center)
4) stroke (Need to remove 1 side and fully extend and retract. The loader geometry may or may not allow full extension and retraction.)
5) Cylinder end mount style, width and pin diameter.
6) Rod end mount style, width and pin diameter.

Surplus Center - Hydraulic Equipment Electric Motors will often have the cylinder you need in stock. They sell mostly new, but do have some surplus ones too. Easy to tell the difference.

I would go to surplus center and find a replacement that was 1/2" bigger in bore and 1/4-1/2" bigger in rod diameter. You will need to do some investigation on your loader to determine how much "slop" there is in cylinder stroke -> extension.

 

[woodlandfarms]

Wow. Great info guys!!! Still not sold that this is the solution. The cylinder still works fine, but the rod has a subtle bend to the left. Not going to do this until the winter, but wanted to get it into a budget now.

Thanks to all

Carl

 

[BillyP]

Wow. Great info guys!!! Still not sold that this is the solution. The cylinder still works fine, but the rod has a subtle bend to the left. Not going to do this until the winter, but wanted to get it into a budget now.

Thanks to all

Carl

If it ain't broke, don't fix it

 

[joe48]

fortunately you have a number of choices you can make, all depending on some other facotrs like;
1. do you have the time , 2. do you have the tools, 3 do you really want to tackle this, 4. how much do you want to spend?

choices are;
1. drive over it like suggested ( not the best ,but doable)
2. if access to a press straighten it yourself
3. if there is a local machine/hydralic shop take it to them
4. bite the bullet $$, and buy a new cylinder from the dealer, (may not be all that expensive)

5.one more choice call the guys at CYLINDER SERVICES in rochester ,NY, phone is 585-328-0670. They are one of the best hydralic repair shops in the US. They get jobs from all over the country, and are one of the few that can repair monster cylinders (I've seen some in there that had to be 2 ft in dia and 15 ft long). they also do all makes of pumps ,hydro drives etc.

Just give them a call they are very willing to give advice over the phone.

Good luck, Joe

 

[sandman2234]

Actually I think cylinders with bends actually do tend to wear out some of the part inside due to alignment problems. Take it apart before you order parts for it to make sure nothing is beyond tolerence. Yours may not be bent enough to cause serious wear, but think about the alignment of it as it sits in the housing retracted. A half inch overall makes quite a problem when the tolerances are in the thousandths.
David from jax

 

[JerryG]

Carl,
I didn't notice anyone saying anything about replacing just the rod. Over the years I have had several rods replaced. It is a lot less expensive than buying a whole cylinder especially compared to what a dealer would charge. Any good hydraulic shop can replace the rod. But, before buying anything I would try straightening it first. I have straightened a lot of them and it works a lot of the time. If bending it was just a fluke, then straightening it might last the lift of the machine.