D - Series Questions

[leeave96 487]

When I got into Wheelhorse tractors about 15ish years ago, I never knew there were D series tractors. I saw a beat-up one at a dealer for service one time. I don't recall seeing to many of these at the Wheelhorse shows in Pa (though I wasn't really looking for them).

Tell me about these D series tractors (not the D-250 which I think is completely different). When were they made? Who were they marketed to - home owners or commercial/instructional use? How are their drive trains different than a C series? Who did they compete against?

Thank!!!

Bill

[KC9KAS 4,741]

Well, it looks like the "D's" started in 1974. There was a D-160, D-180, and a D-200 for 16, 18, and 20 hp. All Kohlers engines with automatic drive.

In 1976 the 160 was an ONAN engine, and no 180, but the D-250 came along with a 20 hp Renault engine & 10 speed trans.

In 1977 it was only the 200 & 250.

in 1978, 1979, & 1980 it was the 160, 200, and the 250.

In 1981, it was the 200 & 250

[JamesBe1 80]

There is lots to be said about the difference between the D series and the other series Wheel Horses.  One of the most prominent is the split hydro system.  The pump and motor are connected with a manifold that runs the length of the tractor.  The pump is directly connected to the 16/18/20hp engine, and the hydro motor is directly connected to the transmission in the rear.  It makes for some real interesting repairs.

 

Over the years, people have been making an effort to pool thier knowledge regarding the repair of the hyrdo components since most parts are unavailable or very expensive.  There are a couple of real good threads here on hydro pump repair.  Coldone (Britt) even has some great videos covering refurbishing pumps and motors.

 

The D is a lot bigger and heavier than the other series, and often (not always) accompanied with a rear PTO.  Unfortunately, the PTO speed is 2k RPM, and most attachments other than wheel horse, run at 540 rpm. 

 

Not sure what else to talk about.  They are ugly, but they grow on you.

[wheeledhorseman 573]

I'll add a little more - the engines are mounted longitudinally with a PTO arrangement at the front of tractor and the hydro pump unit mounted behind. The tractors came in a basic form with optional extras that included a front to rear PTO shaft with CAT 0 couplings front and rear, a CAT 0 three point hitch, and turning brakes for the rear axle. The mid hitch was hydraulic and a standard feature and some of the plumbing was in place to take the optional rear three point. A FEL was also available. The D-250 was not a Wheel Horse at all, it was built by Gutbrod in Germany based on their 2500S I think.

 

These were all designed with heavier work in mind than the smaller horses but marketing material continued the tradition of portraying WHs in a home rather than agricultural situation. 

 

 

Here in the UK relatively few were sold, mainly I think due to the cost which was similar to an average family sized automobile and more expensive than some small agricultural tractors. You only have to tear one apart to discover that they couldn't have been easy to assemble in the first place which must have added to the cost. I get the impression thet here they were purchased in the main by small horticultural businesses or for grounds maintenance on country estates.

 

The choice of CAT 0 as the standard together with the PTO speed meant that you were pretty much limited to buying WH attachments to go with it - another reason I guess that they weren't great sellers this side of the pond.

 

Many will think them ugly but they have a certain charm that grows on you and takes control just as it does with other WHs. I recently picked up a second D to add to my stable. 

 

Andy

 

 

[JackC 616]

Lots of D discussion this month for some reason.  Lots of good information.

One of the common comments is "they seem ugly at first but grow on you."

I too thought they were ugly at first but now for some reason they look great to me.  

Beefy.  I have two D-160s.

 

Great picture from wheeledhorseman.  That is a thing of beauty.

Perhaps, you need to own one to appreciate one.

 

The "D"s are the draft horses of the brand born for heavy work.

[Trouty56 565]

IMHO I think the D series tractor was WH's attempt at jumping on the Cat 0 3 pt bandwagon.  Other companies started using them also.  Rear attachments were developed specific to the Cat 0 pto standard.  But alas, the Cat 0 was short lived as companies started using the Cat 1 3 pt with the lower pto revolution on tractors not much larger than the D.

[KC9KAS 4,741]

Wow, this picture is so 1974! Well, anyway the guys hair is 1974!

[leeave96 487]

So I gather the D-series had no drive shaft to the tranny?

[Trouty56 565]

No...the engine is connected directly to the pump.  If you are familiar with the automatic transmissions from the mid to later 70's instead of a belt turning the pump/motor combo the pump is separated and directly connected to the engine.  The oil from the pump is transferred to the drive motor through a manifold. 

WH had a lot of faith in the hydro systems.....a drive shaft with an multi-speed transmission would have been cool.....

[leeave96 487]

I may have to go to the Wheelhorse show in June to see one of these D series tractors first hand - LOL!

 

So the pump was then between the engine and tranny?  Was the tranny the same unidrive used on the C Series or something different?  Was it a Wheelhorse tranny?

[refracman 166]

The pump was directly coupled to motors flywheel, the hydro pump, drive motor and trans were the same as the C series with the only difference being the axel length. The casings had some minor diferences but the general castinigs are the same.  .

 The pump has issues mostly because of the size, one being to small for the almost doubled weight of the tractor and large implements it could handle and the other was the the coupling between the motor and pump imput shaft could fail and it will strip this shaft.

  The trans differential can fail due to the axles being longer and thus moving the weight further out and causing the outer axel bearing acting as a pivot point causing the excessive strain on the differentail. This caused the bolts holding differential to fail. WH update to this was first to install hardend washers on one side, then both and finally to solve the issue, upgrade from 5/16 bolts to 3/8ths bolts.

 There are several other issues the D series had early in its production but by 1980 most were resolved except the undersized hydro pump and motor.

[chrisd200(inactive) 55]

I have owned a few wheel horse tractors over the years and still have my first one, a D200. I bought this tractor back in early 2000 from the original owner who just happened to be my next door neighbor. So i was fortunate enough to grow up along side this tractor and therefore I pretty much know its entire history as I helped my neighbor maintain it all of those years. Since day one this tractor has maintained an average of 4 acres having to do some type of chore almost daily...... mowing, tilling, gardening, plowing, hauling and anything else. It did a fantastic job for the first owner and I certainly have NO complaints!!! I do not feel that they are difficult at all to work on when you compare them to some of the Cub and John Deere tractors (like the 400) that were equivalent to the D series. I also work for a Kubota dealership so maybe the D series has spoiled me as Kubota's compact tractors can be very difficult to work on. When it comes to pulling power and hydro pump size, I have heard guys before saying that they were underpowered. but I am not sure what this is based on. Not to argue or dispute but My tractor is an early model D200 and it has always impressed people with its pulling capabilities. The big 50" tiller is pulled through hard ground with ease, I can rip this good old southern red clay with a 12" plow and the engine seems to work harder than the pump. This is the type of work this tractor has done its entire life and the pump was just rebuilt for the first time about 3 years ago. The only problem I have had was with the pto clutch. Finally got tired of messing with it and converted it to a HD electric clutch. The engine has never been gone into as it is the Kohler K532 and i believe it was more of an industrial grade of engine similar to the Onans. The way the rear pto works is probably one of the best and simplest designs i have seen on small and large tractors. Very durable and easy to maintain but it is the 2000 rpm set up so finding attachments isn't fun. Steering box has a lot of play and I think that is common for these tractors now at this age. Gotta love a D!!!!!!!

[Swemill 66]

Great info here and i also must agree, gotta love a D! I have only had mine a few years but it seems very reliable!

But what about the steering box? Isn't there any fix for this because mine seems also rather sloppy...

[chrisd200(inactive) 55]

Took my box apart only to find its just worn out. The worm gear has too much wear for the adjustment to do anything. When I tightened it down a little, everything just "bound" up. Had to loosen up on the adjustment so I am back where I started. A few years ago I found a guy on ebay who claimed to be re-building these boxes. I have never found him again....... that might be telling me all i need to know about that. Good Luck and if you find something please let me know!!!!

[Swemill 66]

Ok. Is the only possibility to adjust inside the box? 

[chrisd200(inactive) 55]

External adjustment on the box. Its a jam nut with a big screw. Loosen the nut and you can turn the screw in just a little with the hope that you are moving it off of the worn area. Didn't work for me though.......... worm gear was too worn.

[bewford 21]

The steering box is a Ross, if you do some searching at swap meets you should be able to find a good donor for parts. These were used on cubs and Johnny deeres. My experience is that finding one that the tube and worm gear shaft is long enough. There is also a bearing up grade for these boxes, that's suppose to make them turn easier turn turn. My buddy is a cub guy, told me about it.

[bewford 21]

Here's the video of the bearing upgrade.

www.youtube.com/watch?v=x9rGA_BePMo

Here's another way it can be done

http://www.mytractorforum.com/showthread.php?t=91855&page=2

[bewford 21]

Here you go: McMastercarr.com/Bear'g PN: 5909K32 (1ea), washer PN: 5909k45 (2ea)

These are the parts for the second upgrade listed

[bewford 21]

And the bearing for the first upgrade is a NICE 605, as listed here

http://cubfaq.com/steeringrebuild.html

[chrisd200(inactive) 55]

Good to know, gonna seriously look into this!!!! The big D could use some help in the steering department

[wh500special 2,053]

I've owned all of the D-auto models at one time or another but only kept the 1973 18-Auto as my "collectable."  So I'll toss my 2 cents in the fountain...

 

I've never been overly impressed with the abilities of the D-autos compared to the C-series, but they certainly have their following.  I always felt that they wanted for traction, especially when equipped with the floatation turf tires on the rear.  I tried plowing snow with a 56" blade on my D160-K and didn't find it very satisfactory.  On my D180 the snowthrower was so heavy on the front that even with wheel weights and extra ballast hanging on the hitch I couldn't get back up my driveway when the blower was lifted.  Both tractors had weights and chains.

 

They're also not particularly manueverable.  They have a wide turning radius and slow steering that made them uncomfortable (for me) to use for mowing.  I'm not sure if the available turning brakes improve this much.

 

The engines used seem to put out obscene amounts of power, so you'll seldom overwork the engine on a D.

 

The tractors were decent machines, but they did have some problems that years of (mis)use can highlight.  For example, the early D's and all of the 18-Autos had 3/4" diameter front spindles.  These were prone to breaking even without the added stress of front implements.  Retrofits to 1" spindles and axles cured that.

 

The steering boxes seem to get very loosy-goosey over time.

 

The transmission itself seems to be a bit undersized for the tractor.  The hydro used was also used on much smaller C-series tractors and seems more vulnerable to overheating and premature wear in the D-autos.  Transmission temperature gauges were fitted after the 1974 revision and later a transmission cooling fan was added to help alleviate the heat.  I think the size of the tractor and its big implements (like the 56" blade or the loader) set these things up for abuse.  At some point, 1975 or 1976 I think, Wheel Horse added a pressure relief valve to the transmission bolted to the frame behind the left rear tire to help absorb spikes (and damage) from hard use.

 

These improvements, I think, indicated that the hydro unit was a bit marginal for some applications.

 

The divorced hydro pump and motor was actually, in my opinion, a brilliant idea.  Why run a long shaft or belt from the engine to the transmission when a couple of pipes could do the same thing?  Simple and effective. 

 

The differential bolts have already been mentioned.  It's not terribly uncommon to find a tractor with a welded transaxle casing from one of these errant bolts getting pushed through the cast iron.

 

Speaking of transaxles; in/around 1976 Wheel Horse relocated the parking brake control from a separate control on the dashboard to the Direction Control Lever (DCL).  The DCL, then, had the obvious positions of Fwd-N-Reverse but also added a Park position accessed by pulling the DCL rearward into a separate slot near the Reverse position.  The Park position engaged the parking pawl inside the transaxle (another weak spot). 

 

Anyway, apparently this reconfiguration caused problems with operators shifting into Park while still on the move which, of course, introduced the possibility of causing internal transaxle damage.  One guy I talked to who has scrapped probably a couple hundred D-autos over the years said it could even cause the transaxle to drop out of the tractor if the loads were high enough and the traction was good enough. 

 

The Parking brake control was later moved back to the dashboard and the extra slot was filled with a bolt-on plate.  Eventually, a contracting band on an external drum replaced the internal pawl on all Wheel Horse hydros including the D.

 

But they did offer some big attachments and a lot of guys really like them.  Strangely, the biggest belly deck ever offered was a 48" unit.  But 60" and even a 72" rear mower (from Woods) was offered.  The 72-incher is exceedingly rare and I've only ever known of one of them that Jim M had.  54" and 56" front blades, 50" mid blades, Ark 550 loaders, 48" thrower, and - of course - the backhoe attachments were offered.  You can see that the dreams and plans for the D-autos were big.

 

The 50" tiller is a brute.  Early versions were actually 38" in width with optional extensions for the total 50" width.  But be advised that the input gear tends to be a bit weak and the tiller should NEVER be used with the 3pt hitch set up to provide down pressure.  It can overload the tiller and can lift the rear of the tractor enough to propel it forward with considerable and uncontrollable eagerness.

 

The market was for "estate" owners and pretty much whomever now would be buying a Sub Compact Utility Tractor.  They remained in the lineup a long time and must have acheived pretty good sales considering how expensive they were. 

 

1973 marked the introduction of the series with the 18-Automatic.  In 1974, the tractor was mildly changed (the dashboard changed to include more gauges, the parking brake lever moved from the "hump" to the dash, and the space under the hood grew taller by about an inch) and the D160 with a Kohler k341 single cylinder joined the lineup, the D180 with a Kohler k482 replaced the 18-Auto, and the D200 with a k532 was added.  The D160K was a stripper tractor with no headlights, a simple seat, and smaller engine.  The top line D200 was fully dressed with PTO/3pt/and turning brakes.  D180's and D200's had a "suspension seat" mounted on a big spring and easily adjusted forward and aft.  I think the seats themselves were different.  And the D200 had a 5-gallon gas tank whereas the others were smaller.

 

In 1978 (I think) the 16-kohler was dumped for the Onan 16 horse twin BF-something.  The D180 was dropped.  And the D200 soldiered on.  I think eventually the 3pt was added as standard to all D's.   Probably to use up parts or something.  The C195 and D250 experiments and the end of the run for the D-autos put the nail in the coffin for WH dipping a toe in the larger tractor market.

 

I too found implements hard to find, but 3pt/PTO attachments can be had if you look outside the WH family.  The 2000 rpm rear PTO and the cat 0 hitch really became the standard for many garden tractors up through the 1980's or 1990's.  Deere and Cub Cadet (probably others) offered 2000 rpm bush hogs, tillers, and finish mowers.  The location of the PTO shaft itself was a bit goofy on some Cubs that might make their implements hard to interchange, but there is more out there than I first realized.  The D250, on the other hand, is really wacky with a 1000 RPM PTO that spins in the opposite direction (CCW).

 

The D-autos were GOOD tractors.   But not great.  The C-series were GREAT tractors.

 

Wow, that's a lot of typing for 2 cents.  Not necessarily much value though.

 

Steve

[bewford 21]

The ultimate steering upgrade is powering steering. Member here Rob screen name (roblawrence) has made kits for the Ds. I have drove his D200 with loader it's a dream.

[chrisd200(inactive) 55]

That would be awesome

[leeave96 487]

Thanks everyone!

 

Steve - GREAT write-up!!!!!!!!!