Farming newbie needs help with implement repair

[tmac196]

I am new to farming my 8 acre hay field which I use to supply forage for our horse farm. I recently purchased a New Holland 255 Rake/Tedder on consignment from my local CNH dealer. During the initial shakedown run, operating at about 350 RPM on the PTO one of the twelve arms which holds the tines flew off. Inspection revealed the "Split Tension Pin" (as I have subsequently learned they are called) holding the arm to the rotary wheel frame had apparently migrated to one side allowing the arm to detach. I have attempted to remove the pin using hand tools (Ball Peen hammer, penetrating oil, large channel locks in an attempt to pinch the pin and rotate it out) have been fruitless. I need to remove the pin in order to inspect it for damage and, if need be, replace it. I have enclosed some pictures of the problem, which my Mac wants to rotate horizontally instead of allowing me to change their orientation so feel free to rotate your monitor to view correctly.

The tedder/rake missing one of the left-sided arms:


A normal-appearing split tension pin for comparison (the tine arm is yellow, the rotary frame is red):



Bad pin which has rotated out on the right side of the arm which flew off:



and in on the left side of the arm which came off:



Questions:

How do you remove split tension pins?
Rusted pins are a guarantee. How do all of you deal with the added problem of these pins being frozen in place due to corrosion?
Is the process of reinserting a pin just the opposite of removing one?

tmac

 

[npalen]

Applying some heat to the outer member holding the pin will usually help break it loose. A Bernzomatic torch with Mapp gas applying the heat will also swell the outer member making it easier to get the split bushing/pin out. Wouldn't want to get the bushing/pin too hot though as it might lose it's temper but might be a good idea to replace it with a new anyway.

 

[Bison]

.
Don't know what you mean with split tension pin?. Only terms i know is a roll pin(small steel tubing with a split along its entire length or rolled up sheet metal ) or a cotter pin(solid half round wire folded back on itself to form a round split pin with an eye on one end) in any case cut the pin off flush with the tubing and use a fitting punch and hammer it out. New pins can be had at the dealer, a bolt supply or farm store.
Roll pins go in the hole tight,the pin is supposed to be slightly bigger than the hole it goes in, friction keeps them from moving
Cotter pins are slightly smaller than the hole cause you bend the protruding ends outward to keep them in place

 

[tmac196]

.
Don't know what you mean with split tension pin?. Only terms i know is a roll pin(small steel tubing with a split along its entire length or rolled up sheet metal ) or a cotter pin(solid half round wire folded back on itself to form a round split pin with an eye on one end) in any case cut the pin off flush with the tubing and use a fitting punch and hammer it out. New pins can be had at the dealer, a bolt supply or farm store.
Roll pins go in the hole tight,the pin is supposed to be slightly bigger than the hole it goes in, friction keeps them from moving
Cotter pins are slightly smaller than the hole cause you bend the protruding ends outward to keep them in place

It appears that the Split Tension Pin and the Roll Pin are one in the same based upon your description.

 

[DJ54]

What would it take to drop that whole arm assembly off..?? IF it's not too big of a deal, I'd get it off and lay it on something solid, so as to drive that pin out. Just looking at it suggests your getting a lot of spring action when you hit it.

A sizeable drift punch, or home made punch from a grade 8 bolt. Either weld a handle onto the home made punch, or a pair of vise-grips on the drift, and a minimum of a 3-4 lb sledge, and HIT IT..!! And yeah, make sure you have goggles on...

A good penetrant recipe I got from here of a 50/50 mix of Acetone/Auto trans fluid outshines anything I've bought off the shelf (PB Blaster, Kroil, etc.)

If removing is too much of a hassle, then you need to block it solid, or buck it with a sledge on the other side, to take the movement action, that I would guess is absorbing the driving force you're applying.

 

[npalen]

http://www.huyett.com/catalog/pages/Pins/TB-TensionBushing.pdf

 

[Beltman60]

Kroil is the best penetrating oil
now with removal of the pin make sure your punch you use is close to the size of you pin
if not too small of a punch and all you will be doing is expanding the pin when you hit it

 

[k0ua]

I have always used Kroil, but I have heard the acetone/autotrans fluid is good too.. a roll pin technically requires a roll pin punch, it has a domed center and a flat edge to prevent damaging the pins. Soak it in your choice of fluids, and back it up good with either on a bench or a sledge, and knock the "dog poop" out of it with the proper roll pin punch. "split tension pin" is a manufactures name for a roll pin

http://www.grainger.com/Grainger/WESTWARD-Roll-Pin-Punch-Set-2AJL9?Pid=search

James K0UA

 

[Bison]

Penetrating oil will have no effect on a part that is press fit.There is no space for the fluid to creep in.
Heating up and cooling down and brute force is the only options to try break the hold

 

[Beltman60]

a spring pin is not a press fit

 

[Bison]

a spring pin is not a press fit

OK, hammer fit then?,..outcome is the same

 

[tmac196]

Thanks for all of the advice and the suggestions. THe roll pin punch sounds ideal, but the configuration of the implement, with 6 tine arms radiating from a central rotating head, makes it difficult to get around the arms on either side while using a 6-8 inch long roll pin punch as there is no space left to bring a heavy mallet of hammer to bear. It is an exercise in frustration.

I spoke with the CNH dealer and looked the part up online. They would be happy to order one for me. It is a 16 x 140 millimeter roll pin and they will sell it to me for $24.77! I nearly spit my coffee out all over myself. I asked him again, "Did you say twenty-four dollars and seventy-five cents?" He replied in the affirmative...before tax.

My next phone call was to a local Fastenal store. "We don't have metric roll pins in stock, but we can order one for you. I'll look it up and call you back on the price." He hasn't yet.

So...I may try taping a 16 mm socket to the exposed end of the existing roll pin and heating the rotating head which it is inserted into and then pounding on it. I'll let you know how I progress. I'll also look for a suitable roll pin online.

tmac

 

[k0ua]

Wow, that does sound like a bunch for a roll pin.. I was thinking a couple of bucks, would be Ok for one that big..Good luck with it.

James K0UA

 

[Bison]

Can't you use use a long bolt or a 5/8 rod and tack weld it in place.
There is plenty ways to skin that cat.

 

[tmac196]

Bison,

Those are good ideas. I am more partial to the bolt as this fastner needs to be removable for tine arm installation and maintenance. Thanks.

tmac

 

[tmac196]

Update:

The problem is solved. Closer inspection revealed that the roll pin actually broke on the one end holding the tine arm to the rotating hub and when it did, the torque of the 15 lb tine arm actually bent the remaining portion of the roll pin in such a way that it was bent upwards over the top of the hole in the rotating housing that was meant to be pounded through. The end which remained sticking out of the other side (see pictures from initial post) was so rusted in place that the was no way to twist or pull it out. After 2 hours of various attempts to pry the torn end down to align with the exit hole which were fruitless, my neighbor (80 year-old farmer, been-there, done-that) suggested we try to cut the pin in place and haul it out in pieces. Neither of us had an oxy-acetylene torch, but I do have a Dremel and one 1-1/2" cutting disc on it with no spare...to be used against hardened steel.

The good news is that that Dremel disk cut through that steel roll pin like butter and once cut in half, it was easy to remove the rest of it.

30 minutes later we were finished and now I am back in business.

The lesson learned: Keep thinking. There are many alternative ways to fix a problem and always, always trust an old farmer.

tmac