Why I am not big fan of electric PTOs

[pfrederi 17,856]

I do not like the violent sudden engagement of electric PTOs i prefer to feather a manual.  Started working on a new to me Electro 12 that had an electric PTO.  Look at the PTO key.  I have seen damaged keys but this one obviously beat itself  over the years.  I am not sure what implement she will be married to but I may put on a manual PTO.

[953 nut 55,739]

The only electric PTO I have is running the hydraulic pump to a Johnson Workhorse FEL on my GT-14. Sudden engagement is not a concern for me, but if it is engaged and I have the lights on the charging system is being overtaxed, probably not going to change to manual clutch (too lazy), but will probably change the lights to LEDs. 

[WNYPCRepair 1,921]

I cringe every time I engage mine. 

[cleat 6,320]

My Ford had an electric PTO. I tried to have the engine idled down when engaging the PTO no matter what it was connected to (I only had a mower deck and snow blower for it).

 

I do like to be able to gently engage the PTO. My diesel tractor has a 2 stage clutch and I can slowly let it out and gently start things connected to it as well.

[tractorhogg 612]

My Allis 416H turns on like a whisper, as does my Massey MF16 and MF1450, My Ariens GT14H's have electric clutch front and rear and they are very quiet turning on, maybe its the design. The engine sideways being stressed on a 90 degree angle could have something to do with it.

[Tankman 3,518]

Prefer the manual PTO's.

 

There's just something "abrupt" when engaging the 'lectric PTO unlike "easing" the manual PTO into action.

I like to spin my mower decks on slowly.

[cleat 6,320]

It may be in our minds as well because your car A/C unit cycles on and off as you drive with no ill effects.

 

[tractorhogg 612]

Heres the shaft and key from my 1974 Allis 416H, that was a new block in 1989, still that was 26 years of hard mowing by the guy I got it from

[pfrederi 17,856]

I think the one on right might be a bit jerky when engaging.  I had never looked inside an Electric PTO before...Interesting

[WHX?? 49,143]

Pretty much the same as a air conditioning clutch Paul, A/C & hydraulic  clutches don't engage as hard because refrigerant/oil absorbs much of the starting shock. The rust on the left one will clean itself off after some use but the dust it leaves behind should be cleaned/blown out occasionally. Biggest problem I have with these pto's is bearings My 246  eats the bearings quite often suposedly beacause of the heat generated But I think it's beacuse water gets in the bearing when washing (vertical shaft). Bearings are staked in so a bear to get out the first time.

These guys https://xtremeope.com/  have replacement electrics that are supposed to be much better and cheaper. I with with you guys on rather have a manual tho.

Edited March 28, 2016 by WHX61/3

[tractorhogg 612]

1 hour ago, WHX61/3 said:

Pretty much the same as a air conditioning clutch Paul, A/C & hydraulic  clutches don't engage as hard because refrigerant/oil absorbs much of the starting shock. The rust on the left one will clean itself off after some use but the dust it leaves behind should be cleaned/blown out occasionally. Biggest problem I have with these pto's is bearings My 246  eats the bearings quite often suposedly beacause of the heat generated But I think it's beacuse water gets in the bearing when washing (vertical shaft). Bearings are staked in so a bear to get out the first time.

These guys https://xtremeope.com/  have replacement electrics that are supposed to be much better and cheaper. I with with you guys on rather have a manual tho.

It's the quality of the bearing/bushing that is the problem, sort of, The bushing cant be harder than the crank, which these days is softer than it used to be. Because a vertical shaft revs higher it creates higher temps, a harder shaft may be effected more by heat (break not bend) than the softer shaft, ergo a softer PTO bushing

[Aldon 4,827]

8 hours ago, pfrederi said:

I think the one on right might be a bit jerky when engaging.  I had never looked inside an Electric PTO before...Interesting

 So is there anything to be aware of in taking one of them apart? Do you know if bearings are available to rebuild them? Mine is making some sounds like it may have some rust or something when I spin it by hand. I have been holding off taking it apart as I have never seen anyone post such as yourself that they did so.

Edited March 29, 2016 by Aldon

[ztnoo 2,298]

The key on my K341 that I had out last week in my clutch pulling adventure to get to the hydro drive pulley, looked brand new compared with pfrederi's.

But the only thing I've ever done in 35 years of owning my GT 14 is mow with it, and before that, my best guess is all it ever did was mow.

So as far as running attachments go, I'd say an electric clutch running a mower deck (with two drive belts to absorb shock during engagement) likely has a lot less long term abuse and load, than an electric clutch that maybe runs a snowblower, for instance.

My key had some very slight wear along its length, but perfectly square on the top side of its 3 1/8" length.

I'm glad I caught the somewhat loose hydro drive pulley when I did however. If it had gotten looser, my crankshaft key might have looked like that one before too long.

I put it back together with Loctite Red in the key slot (on the crank itself, not on the top side which comes in contact with the hydro drive pulley and the clutch pulleys), and Loctite Blue on the two allen grub screws on the drive pulley, so hopefully it will stay put for a long time. At least I know to keep an eye on it now.

Edited March 29, 2016 by ztnoo

[pfrederi 17,856]

11 hours ago, Aldon said:

 So is there anything to be aware of in taking one of them apart? Do you know if bearings are available to rebuild them? Mine is making some sounds like it may have some rust or something when I spin it by hand. I have been holding off taking it apart as I have never seen anyone post such as yourself that they did so.

 

 

I will post some pictures of how to take them apart later today.  (The Service Bulletin Pics are terrible

 

The small bearing is for sure available.  I read that the rear bearing (big one) was NLA.  My bearing guy thinks he found it and it is on the way to me.  I will let you know after I see and check it.

[ztnoo 2,298]

Do you need a hydraulic press to get them apart?

[WHX?? 49,143]

I didn't need a press but it would have made life easier. On mine the biggest problem was it was rusted on the shaft and I had to use a puller to get it off. The pullys were made of stamped steel and bent meaning the whole assembly had to be replaced to the tune of 285 from a dealer. The one Paul is showing looks to be cast. I antiseized the whole thing  going back on so three years later when the bearings started to growl again it slid right off. I don't know if you should antiseize it or loctite it Paul. Given the looks of your keyway maybe red loctite but that would meat heat if it had to come back off... ..

[ztnoo 2,298]

Well, everyone's situation is a little different, and ultimately lots of things are individual judgement calls with input of course from places like RS usually welcomed.

If my key had been like the one in pfrederi's first photo, I would have definitely been replacing that.

Things like that can put pulleys are risk, as well as the crankshaft itself.

I wouldn't dare risk things with a beat up key like that.

Just one man's opinion....

[pfrederi 17,856]

I will do this in a couple of posts...(so I don't confused)

 

I am disassembling 3 WH Electric PTOs.  I assume youhave already removed from teh tractor using a pusher bolt.  5/8NC or 7/8NC or 1"NC depending on the age of your PTO

 

First picture are the tools i used Who ever made these for WH they were not consistent in the style of snap ring. The Eaton type require a special pliers or you will probably damage it (or your self removing it.  The big internal snap ring on the right can be removed with a couple of screw drivers.

 

Next step is to remove the electro magnet (field Coil).  Note on older units with a 7/8 or 1" pusher there may be a snap ring you have to remove between the outer bearing and the field coil. Newer units do not use that.

 

Thread the 5/8" nc bolt into the unit from the outside Picture 2 make sure the threads are fully engaged. Manual says use cement floor i used an anvil and proceed to slam the unit down on the bolt head several times...and I do mean slam.Picture 3.  You may want to put a small amount of Kroil.PB Blaster in the seam between the inner bearing race and the PTO sleeve. After several hard slams the field coil will drop out Picture 4.  You will then have 2 parts picture 5.  Time for a coffeee break.  More to follow

 

 

[pfrederi 17,856]

Next step is to separate the pulley from the hub.  I have both 1" and 1-1/8" PTOs  The only difference is the hub.  They use the same bearings Field coil and Clutch plate.

EDIT::

First you have to remove the two snap rings inner and outer.  See last picture I forgot this step.  Inner is an eaton and needs the special pliers or 4 letter words and some luck.  The outer one you can pry in and off with a screw driver.

END EDIT

 

 

This time thread the pusher bolt in from the back of the unit. Again make sure to fully engage the threads.  Again slam the unit down on the anvil until the pulleys drop down (some Kroil PB blaster Between the inner race and the hub may help Picture 1.  Picture 2 shows them apart.

You can now press out the bearings if you are replacing them.  The small bearing in the field coil is readily available for about $8. 6204 is bearing size you want one sealed on both sides. On one of my units they staked it in so it will come out hard.  I used hydraulic press. I guess you could use a hammer and appropriate arbor but I would be afraid of damaging the field coil.

Picture 3 shows the old and new bearing.  I inserted new bearing with a hand press.

 

After break we will remove the big bearing  which may or may not still be available (I should know in a couple of days).  In any event you could always clean and repack the original after you get it out.

Edited March 29, 2016 by pfrederi

[ACman 7,618]

On the Grazer mower I used as a kid , I would rock the pto switch back and forth at a lower rpm so the blades would ez into engagement . In my later years as a od grinder we would spin the grinding wheel by hand then hit the on off switch a couple times so that it wouldn't knock my wheel out of  balance (+-.0005 on some jobs) . Seem to work , and the belt didn't shriek when you turned it on .

Edited March 31, 2016 by ACman

[Aldon 4,827]

@pfrederi , I really appreciate you posting this process and the detailed explanation and pics!

[WHX?? 49,143]

1 hour ago, pfrederi said:

On one of my units they staked it in so it will come out hard. 

I used a dremel with a thin cutoff wheel to grind out the stakes so it would come out easier.

 

Am I looking at this pic right and the key looks like it is worn down below the crank slot or sheared right of!?!?  It looks like a key that is common to  pto and drive pulley??

3 hours ago, ztnoo said:

If my key had been like the one in pfrederi's first photo, I would have definitely been replacing that

Oh for sure if I'm seeing what I think I'm seeing.

[ztnoo 2,298]

Ditto to Aldon's statement.

Very detailed and definitive instructions and phenomenal pics to go with the text!

Great stuff, Paul!!!

[WHX?? 49,143]

How do the bores look that were riding on that crank? I would tthink the bores/bore key slots would be banged up as well??

34 minutes ago, Aldon said:

@pfrederi , I really appreciate you posting this process and the detailed explanation and pics!

[pfrederi 17,856]

The bore isn't perfect but it isn't that bad. It is the one on the right.  Bottom line I only have 2 with 1-1/8" hubs so it is proabably going back on with a new Key.  Note the key itself is almost sheared but the keyway in the crank looks good.  New Key time