Winch problem on a fire dept M54A2 5ton

[Guyfang]

Front winch operation starts on TM page 91, paragraph 2-15.

 

[fasttruck]

The winch PTO has 4 positions Neutral lines up with the latch plate (if that is still there), back is power out, forward is lo range power in, all the way to the front is power on high range. The picture in post 17 shows the drum clutch is "in" or engaged. This is a dog clutch and when engaging it may be necessary to jiggle the drum by hand to get the dogs to go in. Disengagement with a load is very difficult. There is also a drum lock on the side of the captstan opposite the clutch. If you have not already broken this, it is necessary to pull it out to rotate the drum. The purpose of the lock, which is a retractable pin, is to prevent the drum from rotating when the winch is not in use. Winches are typically secured after use with the clutch disengaged so no disasters occur if the winch pto is engaged while driving. Pic attached of a winch with an exposed dog clutch tom illustrate what they look like. On truck shown this mechanism is concealed which will keep ice out of it in the winter. A necessary accessory on a truck with a winch is a snatch block with at least a 6" sheave. This is authorized for the OVM on a truck with a winch. The aforementioned drum lock requires attention from an oil can as, if not often used, it will become rusted into position, and if it is in, it will be difficult to release in order to use the winch.

The drum clutch is sued to release the drum to free spool the cable out. It is NOT used to start and stop the winch. That is done with the clutch pedal in the cab and the PTO control. It takes 2ea people to operate a winch safely: one to watch the cable to make sure it reels in properly without jamming, and 1ea in the cab to operate the winch controls. Besides vehicle recovery problems, the winch can become a valuable asset in rescue situations if properly used.

 

[fasttruck]

Additional pics of exposed drum clutches. These are not friction clutches: it is in or out. To engage the dogs it may be necessary to move the drum by hand to align the opposing dogs. When disengaging there must be no torque on the rig or the clutch dogs will be difficult to separate. When the winch is not in use it is recommended the drum clutch be disengaged and the drum lock engaged. The next time the winch is used it will likely be desirable to free spool the cable and the winch is protected from accidental engagement.

 

[fasttruck]

As described elsewhere, if you can get the slip joint on the PTO drive shaft to close up (this will be difficult to do if it is full of dried up grease) this will expose the center part of the broken shear pin which will require a hammer and punch to knock out. This is why a machinists' hammer and a punch is also part of the OVM for a truck with a winch. Then you can rotate the imput shaft on the back of the winch with a pipe wrench to get the tension off the dog clutch so you can release it and deploy the cable.

 

[fasttruck]

Yo9u say your M54A2 has been converted into a tanker ? How much water do you carry ?

 

[gimpyrobb]

Shoot me a PM with shipping info, I'll send a shear pin for free. Doghead had a pile of them, I'll ask and let you know.

 

[gimpyrobb]

Dh should be along soon. He still has stock of shear pins.

 

[doghead]

I have the correct Mil Spec 5 ton shearpins for your truck, PM me your address and I’ll send you some. Just need to go find them... Will report back in a few minutes to confirm I found them. PART # 7409348 NSN 5315-00-209-7979 , 5315002097979

 

[Mullaney]

Additional pics of exposed drum clutches. These are not friction clutches: it is in or out. To engage the dogs it may be necessary to move the drum by hand to align the opposing dogs. When disengaging there must be no torque on the rig or the clutch dogs will be difficult to separate. When the winch is not in use it is recommended the drum clutch be disengaged and the drum lock engaged. The next time the winch is used it will likely be desirable to free spool the cable and the winch is protected from accidental engagement.

Wow... fasttruck That is a really nicely written piece of information on winches with pictures to boot!

Curiosity question: Cable Cover. Is that something that you made or something that was standard issue and 50 years of sun wiped out for the rest of us?

 

[doghead]

I have them in my hand. Will send you a PM.

 

[jasonjc]

This video is for the M35A2 winch but the 5 ton is very similar.

Not my video.

 

[NDT]

Guys quit telling her to use a pipe wrench on the winch input shaft! Nothing worse than having that precision machined surface all buggered up, then the yoke won't go on smooth ever again!!!

 

[fasttruck]

Winch covers were locally fabricated items. I was told their use was discouraged in later years as they retained moisture which accelerated corrosion of the cable.

Pipe wrench worked for me to gently rock the imput shaft to see if mechanism was free and I got the and the end of the drive shaft went back on easily. Obviously if you need a 6' cheater pipe to turn the shaft something is wrong and then you will bugger up the shaft.

On the subject of snatch blocks , the ratio of the size sheave to the cable is 12:1 so 1/2" cable requires at least a 6" sheave. Smaller is bad. Bigger will work.

 

[fasttruck]

Doghead is right: don't make a move without the pubs: operators' manual, organizational maintenance manual, parts book, and lubrication order for whatever you are working on.

 

[fasttruck]

Reference is made to post 1 and 34: The described publications are available in paper or in the publications section on this site. Do your experts know how to adjust the brakes on a M54 ? Where the 45 or so grease points are on it ? Neglect these at your peril. How to check to see if there is lubricant in the gear box for your winch ? I suspect the forest service is not too big on operator and organizational level maintenance until something breaks. Parts are expensive. Oil and grease or cheap. Be guided accordingly. Much military equipment has been destroyed by untrained personnel with unauthorized tools and parts trying to repair it without reading the reading.

 

[doghead]

I suggest that you do NOT use a new shear pin to run the winch in reverse to unbind your cable.

I suggest you get the engagement lever on the winch into free spool. Then pull the cable out.

If you put the pto in neutral and rotate the driveshaft by hand(pipe wrench, or bar through the yolk), you may be able to see the shear pin in the hole to get the hole aligned, then be able to drive the shearpin out. It can be very hard to see.

If that will not work, I suggest you get the driveshaft off at the winch end and clear the broken shear pin from the input shaft. Then reinstall the driveshaft , install a steel bolt and use a large pipewrench to drive the winch in reverse. Do not try to unspool it with engine power to unbind the mess you have now.

Anytime you are doing this and are trying to rotate the driveshaft, the PTO needs to be in neutral.

In order to rotate the winch drum, without using the input shaft, the winch (lever on the winch) need to de disengaged.

If the lever will not disengage, there is tension binding it from disengaging. You will need to turn the input shaft in reverse to get free play to get it disengaged. That lever slides a square set of engagement dogs. They will not release under tension.(that is why you control the winch from in the cab whenever winching).

Never ever use a steel bolt in place of the correct shear pin when operating the winch for winching.

 

[Celticlady]

Update.

I made a shaft adapter. I went shopping in scrap box. Found a cut off hyd cylinder rod end that worked good. I had to bore out the center to fit over the input shaft. Then drill a hole for the shear pin. Then welded on a big 1 5/16 bolt head. The bolt shaft was all buggered up. nice

Put on on the shaft. Got all braced up to pull hard on the 3/4 ratchet and almost nocked my teeth out as there was very little effort to move it. That is good news.

The bad news is the drum moved about a 1/8 of a revolution. Then it stopped moving. The input shaft felt like it just went into neutral. It is snug but very little resistance. Doesn't make any ugly noises. Doesn't make any noise or feel like its clicking. Or does not feel like if it was against broken teeth.

I was able to put the shift lever back into "OUT" easy. I can't move it now.

The pin that is on the left side to release the drum to hand spool is out. SEE PICTURE It is not on the detent. Its just not going in. We were trying everything to get it to release before. I am sure someone pulled that out. If that is out, then turning the input shaft won't do anything.

I never thought to bring my come-along. I could have hooked that to my trailer hitch and wrapped the other end around the drum and hooked it to the chain to give it a tug. I am thinking that now that the tension is released, if I can unwind the drum with my come-along to get the hook untangled, reset the unwind pin and be home free.

 

[Celticlady]

I suggest that you do NOT use a new shear pin to run the winch in reverse to unbind your cable.

I suggest you get the engagement lever on the winch into free spool. Then pull the cable out.

If you put the pto in neutral and rotate the driveshaft by hand(pipe wrench, or bar through the yolk), you may be able to see the shear pin in the hole to get the hole aligned, then be able to drive the shearpin out. It can be very hard to see.

If that will not work, I suggest you get the driveshaft off at the winch end and clear the broken shear pin from the input shaft. Then reinstall the driveshaft , install a steel bolt and use a large pipewrench to drive the winch in reverse. Do not try to unspool it with engine power to unbind the mess you have now.

Anytime you are doing this and are trying to rotate the driveshaft, the PTO needs to be in neutral.

In order to rotate the winch drum, without using the input shaft, the winch (lever on the winch) need to de disengaged.

If the lever will not disengage, there is tension binding it from disengaging. You will need to turn the input shaft in reverse to get free play to get it disengaged. That lever slides a square set of engagement dogs. They will not release under tension.(that is why you control the winch from in the cab whenever winching).

Never ever use a steel bolt in place of the correct shear pin when operating the winch for winching.

Thanks. I didn't see your reply untill after I loaded my update. Don't know why.

After reading your suggestion, I agree and you also validated where I am at . Read my update see if you agree.

 

[Recovry4x4]

The adapter was a brilliant move! Bravo!

 

[Celticlady]

The adapter was a brilliant move! Bravo!

It was one of the suggestions. It worked great. Thanks to the suggester.