D-180 pump coupling alignment ?

[Sarge 3,463]

Got the coupling modified , keyway cut , new spline piece from a later model C welded into it and running into a misalignment issue . Seems like the engine is 1/2" too far forward ??

 

I need this thing tight to the front pump mount so it's got as much of the splines engaged as possible and utilizes the 3/16" wide key to take the abuse I had machined into the pump shaft (that hurt, btw) . I set the coupling within .030" of the bracket , which is where it sat before although previously someone stacked a whole lot of washers between the coupling and the engine's flywheel . Is the rubber puck perhaps backwards , somehow ??

 

 

You can see just how far it's pulling on the rubber section , bowing out the two sides attached to the engine's flywheel .

 

 

Looking closely , the black allen socket set screw holds the key in place tightly - and I mean TIGHT . I want zero movement against those splines - in my opinion that is why these things wear out too easily .

 

b

 

I seem to remember there are two raised portions on the rubber ring - on each side of it and there is a difference , perhaps it's the wrong direction ?

 

Any insights - bring 'em on - it's an odd 92* day here in September and I'm sure we'll pay for it next week ...ugh .

 

Sarge

[R. L. Addison 299]

Sarge - The "D" series I just tore down to sell off in pieces had no washers except between bolt heads and washers, and the flex disc was turned the other way. The wheel Horse seminars I attended said to put Loctite on the splines, but I do not remember the number (grade). Yes I think the flex unit is reversed, and washers should be under the bolt heads. I'll look at my coupling after supper, but the pump end looks to me to be way too close to pump support. Afraid you will have interference.

Ron

Edited September 20, 2017 by R. L. Addison

[pacer 3,168]

Yep, flip the metal part over and it should be OK (Heh! ask me how I found out!!)

["Manic-Mechanic" 1,194]

I saved my tear down pictures, this is how it was set up on the 18 Auto.

["Manic-Mechanic" 1,194]

Also, after the rebuild, it sat the same and there wasn't a whole lot of space between. Perhaps the hockey puck is flipped? Or loosen the set screw and allow the hockey puck to relax, then tighten it back up? Granted the hockey puck is right.........

The parts diagram shows the sequence, which is what I followed,"this time"! Ha ha ha! My memory isn't always enough anymore!

Edited September 21, 2017 by Oldman

[Sarge 3,463]

I know the bolts need one flat washer under the head - that's the standard . I suspect by som e of the other repairs done on this thing they had tried to space the coupling tighter to the pump to save the splines - which didn't work .

 

Per the photos in the Transmission Service Manual and @Oldman I have the metal section (pump end) in the correct direction . What I'm questioning is what direction does the rubber flex coupling sit since it could face either way ? There are raised bosses on the metal inserts that are vulcanized to the rubber disk - each pair of these bosses are different in length from each other depending upon which side faces the engine's flywheel .

 

I'll have to get some pics and measure the difference in those bosses - need to log back on the laptop since I can't figure out how to synchronize pics from the phone to tablet - not a fan so far .

 

Sarge

 

["Manic-Mechanic" 1,194]

I know the coupling had the two spaced portions towards the engine and no other raised or spaced portion on the other side. Then it is the 18 Auto. Also, the manual states "molly grease", not lock-tite. Had me worried if I needed to separate them and apply lock-tite!

 

See Index 31 (Pg 28)

Sunstrand Hydro (part 1).pdf.

 

This side towards the engine

This side mates the driven coupling(metal) The two small raised surfaces. (Notice the wear marks from the flat washers to the coupling, that's the pair of retaining bolts too the flywheel.......)

 

I don't know, your coupling looks right. Maybe the set screw and keyway are too far forward, pulling the rubber? That keyway is long enough to adjust back and forth right?

Edited September 21, 2017 by Oldman

[Sarge 3,463]

I think that was one of like 3 bulletins on that coupling trying to fix the failure issues . I decided to try something different - sourced a later model C series Sundstrand pulley that has a steel machined insert . Chucked that thing up in the lathe and cut the weld out , removed the insert and had it cut for a keyway - which had to be timed to the splines on the pump shaft , not an easy task for the machine shop . They had to make a jig first , cut the slot in the pump (wrecked two milling cutters) and used a wire EDM to cut the insert . I had a local friend machine out the center of the original steel section - which ate the end off a C2 lathe tool and required a C6 grade to cut it out to size . The steel center was pressed into the cast steel section for the flywheel end and welded . That required Inconel and ER80SD6 filler rod with the tig to get it to bite and not crack the weld due to shrinkage rate differences ...simple , right ?

 

 

 

Now , after all that , the splines were far too tight - I had to re-file them by hand due to everything changing shape from the weld . It fits , and fits tightly on the key in the pump shaft's splines - should not work against those splines and destroy them over time - I hope anyway .  

 

I ran out and did some measuring on the rubber ring that was previously on the tractor . I installed a different one that I found used that was a fair amount more compliant - I'd assume they will become harder with age and exposure to the elements .

 

 

One side they protrude 1/8" -

 

 

 

Other side , the inserts protrude nearly 1/2" - 3/8" difference depending upon which side is facing the engine -

 

 

I see now where the problem lies - that difference allows the engine to either sit closer or further away from the pump - just depends on which way it's facing . I'll find out in the morning if I don't get called out .

 

I'll try to remember to get photos of the steel section after it was finished - that was a lot of work . I have some other avenues I can chase down to make these better , but all would involve modifications to the pump shaft itself and using an off the shelf Lovejoy coupling instead of this odd arrangement . Frankly , I'm surprised these things lasted as long as they did - that whole frame on these things flexes when you work them and that alone should destroy these couplings easily .

 

Sarge

["Manic-Mechanic" 1,194]

I see you have a lot of time in on this coupling issue, almost a crime to stop now? So the piece can't be moved forwards and backwards on the pump shaft? I believe you'll get it done and it'll last a very, very long time! Looks really great, nice job getting all that done.......

[Sarge 3,463]

The thing spent 2 weeks at the machine shop alone - their wire EDM machine went down and they had to wait on parts . Seems like the curse followed this thing wherever it went , lol...

 

Going out now to get some more pics and pull the coupling off the pump - will need the 2-jaw to get it off the shaft . It's just one of those things I want to fix once , and never again . Not to mention this thing going down is really hurting getting a lot of other work done before the cold weather hits here - I work outside for the most part .

 

Sarge

["Manic-Mechanic" 1,194]

Oh, yes I have that too, follows me around with everything! I hope you get it squared away soon. I have had a lot of issues with the 18 Auto, but too much into it to quit now. Everything has been rebuilt or replaced! Now the PTO bearing is starting to make chatter again, or the double pulley has gone dry inside? Time to do something with that next! Ha ha ha! I can't even locate a decent volt gauge, everything is junk. Might as well put a ammeter back in with a fuse to the + side.......

[Sarge 3,463]

Here's a 2-1/16" SW volt meter - pricey but fits the bill ....

https://www.summitracing.com/parts/sww-82376

https://www.summitracing.com/parts/sww-82391

Wings style - really sharp

https://www.summitracing.com/parts/sww-82482

If you call them , they can also provide the correct light kit if you want - SW even makes them with a 2-wire harness for an isolated (non-chassis) ground .

 

I got tired of this thing taking far too much time yesterday , so I machined a pair of spacers .280" thick and 1" in diameter on the lathe . This allowed the engine's bolt holes to line up in the frame and put the coupling where I wanted it on the shaft . Not sure why everything is not fitting properly according to the way WH built it - this shouldn't have been a problem . There are a few places on the lower side panels where they have been welded , perhaps those repairs have enough effect on it - who knows ?

 

I did determine that as-stock , the rubber flex ring can only really go one way - with the 1/2" thick bosses towards the engine . Otherwise , the bolt heads in the opposite direction that fit into the steel coupling for the pump will hit the flywheel - they way they had it in there before was wrong , hence the use of washers after they chewed up two of the mounting holes in the flywheel .

 

 

Someone has screwed with this issue a lot in the past and evidently didn't have any of the service manuals or resources to figure it out , years ago that was typical unless you had a local dealer .

 

With the coupling faced incorrectly , I used the new spacers to make up the difference . They could go either way and will fit at the pump side or engine side - depending how I wanted the coupling oriented by using the spacers on the shorter side of the flex ring .

 

 

Installed -

 

 

Here are the mods to the cast section of the pulley - this is one seriously hardened piece of iron and full of casting flaws which made it hard to cut - you can just make out the line where the two different part meet , it's a ring just outside of the splines . That inner part is from the later model Sundstrand - equipped C series with the steel pump pulley .

 

 

 

 

 

We had modified that steel center with the wire EDM machine to accept a 3/16" key - it had to be timed to fit the spline count on the pump shaft - hats off the Rob at Riverfront Machine in Spring Valley , Illinois for making this work . Since I'm not experienced enough with odd cast iron work , Sam Forristal who's shop is next door welded the two parts - had to use a combination of Inconel and ER80SD2 tool steel fillers to make it work .

a

 

This assembly fits the pump shaft quite well . That steel center turned out to be a disappointment as it's pretty soft . I'd say the better way would be to stick with the original cast part (one with perfect splines)  and just have it broached or cut for a key and add a heavy set screw to force it tight to the splines . That little tiny of bit of play between the coupling and those pump splines allows this part to destroy itself - 18/20hp engines driving that small of a shaft is a bad recipe - the torque of the K482/532 engines and no real dampener in the hydraulic system means this thing sees a potentially high shock load - over time that will strip the coupling and destroy the shaft in the process .

 

 

Modern couplings for shock loads use a better dampener and a clam shell design that clamps on the shaft splines - that is a far more robust setup that can take the stress . Not to mention , no one uses a shaft this small nor as short for such a high torque load - pretty much the worst part of this design . The concept of the tractor was great , but between this part and the use of a narrow rear axle housing doesn't allow it to be able to work to it's potential .But still , it's a Wheel Horse and amazingly tough - judging from the damage to the 56" plow frame I'd say it's withstood an amazing amount of abuse already in the 43yrs since it was built . I just wish there was a better modern coupling available to fit this shaft - that would cure the issue and keep these in heavy service for a long time to come .

 

I spun it on the starter last night to prime the pump . After I build the exhaust and fire it we'll see if there are any vibrations - so far it looks like it runs straight enough not to hurt it , time will tell . Now , gotta figure out where the heck I put those exhaust gaskets...long term projects make it tough to keep track of parts around here . Not taking any sort of victory lap just yet - once I get it together far enough to test everything under a load we'll find out - this has been a pretty expensive experiment but not the first around here .

 

Maybe all of this will help someone else down the road , but who knows...

 

Sarge

 

 

["Manic-Mechanic" 1,194]

Wow! That  is the most descriptive rebuild that I have seen on the forum! The final fitment is looking great. I have a 56" Blade, the frame "where it usually breaks" has been welded professionally. I say professionally because I have seen some strange welds on these machine! The Hydro Motor quit on me while using the blade, on a slope and it was wedged between the tractor and the ground! Fun getting that off that day! The spline in my pump looked almost identical to yours, minus the hole. Did you utilize the holes again too? I see the end results are far superior then the factory design. I am shocked that Wheel Horse didn't think things through, but I think also, maybe production was the issue, getting as many done and in less time? I believe your design is great, but not many people possess the skill-set, nor access to someone who does, to do that level of re-fabrication. I say it is a blessing to have a skilled machinist in your area. Having one of these tractors, fully functioning, is a true test of skill, and demands great patience, not to forget $.

[pfrederi 17,672]

The 1981 service bulletin for repair of failed driven couplings had you coat the splines with Loctite RC-680 retaining compound. ( Capital letters do not use grease) Put the driven coupling on and let it cure 24 hours.  Then connect  the rubber coupling.

 

This is a complete change from the 1978 service bulletin that called for grease.

 

 

["Manic-Mechanic" 1,194]

Man, I'd better pull those two apart and get some Loctite RC-680. I was getting confused on that issue! Thank you! Now where to get the splined washer?

[Sarge 3,463]

I believe others have tried to hunt down that splined washer to no avail - none seem to exist except possibly a used one . The hole is a common quick repair fix I did last winter - 1/4" hole and a grade 8 bolt . The splines had been spun already at that point - it wasn't going to do any further damage . I think the only true way to repair these properly is to do some serious shaft mods to that pump and the shaft would have to be removed . Either a new shaft or re-work the splined end into something larger and a bit longer to work with modern couplings that are far more robust and can handle a shock load better .

 

The real problem now is I still don't trust it to last or handle a high work load . That steel center is not a hardened part and even with a key it could wear out eventually with hard work or just from the vibration . I had considered having the machine shop completely design a new coupling and cut it to fit out of D2 steel or something , but the cost of having them plot the entire thing into cad and making the part would have been quite high . Besides , due to the shaft size - at that point you just move the failure possibility to the pump shaft itself and if that fails it could destroy the new coupling in the process .

 

It will be awhile before I even get to fire the engine and put it under a full load since I have to build the new exhaust from scratch - both of the mufflers are totally rotted out . I did get started making the exhaust flanges last night - today is fitting the tubing and extracting the last broken bolt that held the original 90* pipe system to the block .

 

I may try to write a thread on making these pipes - it's commonly available parts and maybe it can help others do some custom work....

 

One of my favorite tools - an older used Milwaukee 62 series portable band saw . I paid $60 for it and so far have only put a new set of guide rollers in it - about $20 worth of parts and the old girl runs perfect . The stand is one I built from scratch - Swag Offroad makes stands like these and have different models to fit nearly any saw made . I totally copied their design off their pics to be honest , minus their miter gauge slot .

http://www.swagoffroad.com/SWAG-Portaband-Tables-Accessories_c_35.html

 

 

You can't beat this setup for cutting small pieces of material . I've used it to cut and shape all types of metal , wood and even rubber . Starrett blades seem to last the longest and a new blade will last an amazingly long time in comparison to other tools . They will cut some slight curves but are pretty limited to mostly straight cuts due to the 1/2" wide blade design . However , other than a larger industrial upright band saw - nothing else will cut thick materials as efficiently . I will give one word of caution - that blade will remove a finger , hand , arm or whatever in half a second and the saw doesn't care either - use a push stick or at least keep your body parts well away from that blade . I added a simple foot switch the saw plugs into - the spring clamp holds the trigger in the on position and you use the foot pedal to turn it on/off . Once the speed dial in the trigger is set to the correct speed for the blade/material to be cut - stomp the pedal and go , I love this thing .

 

 

3/8" thick plate steel - took just a few minutes to cut each one out and the parts are pretty square . I'll use the upright belt/disk sander to finish the parts off smooth and final size them . I have cut through over 2" of solid metal easily with this thing - just requires the right blade choice and proper motor speed selection . Not sure how I ever lived without it prior to building this one - being able to accurately cut small parts and not have to try to clamp them or hold stuff by hand and use other methods that risk injury is nice , I've gotten more than enough injuries over the years as it is....lol .

 

Sarge

Edited September 23, 2017 by Sarge
grammer

["Manic-Mechanic" 1,194]

That is a great machine to have and the stand is excellent! I would love to have such a set up, we had one similar on a job I worked years ago. Nice job on the exhaust flanges! Say, don't forget to make a pair for me too! Ha ha ha! I do have a another shaft for the pump I removed, which still worked but the spline was about all.......I thought I had a bad seal on the flywheel side as oil was gathering and dropping dead center off the bottom of the engine shroud. Here it was the pipe in the block for the oil drain. It was tight but not making a seal, oil would go under the block and then work it's way around! I was dreading having to take everything all apart again! Ha ha ha! I was wondering about how long my pump and coupling will last? Sell it quick! Ha ha ha! No, just kidding. Oh, I don't like the seat bracket assembly. If I put the seat back enough to have room, it'll hit the fuel tank when driving, denting it and stuff?

I need a hoist to get off the tractor! Ha ha ha! I think the oil leak is under control.......You can see I cleaned the spot very thoroughly the paint was washed off!

(all the plumbing was made in the USA)

 

 

Edited September 23, 2017 by Oldman

[Sarge 3,463]

If you have the easy ride seat setup with the spring under it - tighten that adjuster down a bit and preload the spring - it will help it from hitting the fuel tank . I swear WH built almost all their equipment for no one over 5'-2" tall . I've had to modify every tractor I've owned by moving the seats back a bit and raise them a bit - otherwise my knees are doubled back way too far and these days that doesn't work .

 

No idea how well the Loctite will work - they knew they had an issue with these things but never really addressed the root of the problem - they should have had Sundstrand build a more dedicated and heavier pump design for this machine line - along with a much heavier rear axle housing . At that time , the D's were a truly revolutionary tractor historically - this was the first model to dive into the sub-compact category that could handle much heavier work . If a guy can address those two issues - the D is an animal in comparison to modern sub-compacts and much simpler built .

 

I did basically the same thing with the oil drain - mine is much longer to make it easier to dump the oil and not have to remove that heavy front blade I use it for the most .

 

Sarge