ACMOC Membership Benefits

  • FREE quarterly magazine filled with content about antique Caterpillar machines
  • FREE classified listings
  • ACMOC store discounts and specials
  • Full Bulletin Board Access
    • Marketplace (For Sale/Wanted)
    • Technical Library
    • Post attachments

$44 /year ELECTRONIC

$60 /year USA

$77 /year International

D4 pony engine ?s

16 years 7 months ago #9327 by 8C 361
Replied by 8C 361 on topic D4 pony engine ?s
My HT4 has the heavy manual switch for the starter, some of the later Cats use a push button switch through a solonoid. Most guys dont worry about the charging system, it is more trouble than it is worth to keep working. Just use a 12 volt battery and trickle charge it once in a while. It is good to fix that terminal and set it up with a switch so you dont burn the lug.

A lot of us get by with tempermental pinions and latches but you get a gold star if you get it set up right.


Please Log in or Create an account to join the conversation.

16 years 7 months ago #9332 by Old Magnet
Replied by Old Magnet on topic D4 pony engine ?s
Here's some wiring diagrams that might be useful to you:

SJ, I think we have a misprint there as the 933 11A uses the same basic pony as the D2/4.

ttman4, If you copy info to your own files you are safe if the material is removed from the BB........subject to your PC reliability;)

edb, go ahead and remove what ever you need to continue posting. I have copied to files most all the material you have posted, backed up with disc.

Yes, the fuel shut off on the early models is located as you describe........the valve also contains the filter element that is accessed by removing the large nut on the feed inlet side.

Please Log in or Create an account to join the conversation.

16 years 7 months ago #9333 by SJ
Replied by SJ on topic Starting Engine
OM, I have 3 books here on the tractors with the same starting engine & you might be right that the 933 11A was a miss print as the other 2 says 1 qt. At the shop I filled dozens of them but always filled them to full mark on the dip stick & never give it a thought as to how much they held till I checked for this gentleman that needed the capacity.

Please Log in or Create an account to join the conversation.

16 years 7 months ago #9335 by ccjersey
Replied by ccjersey on topic D4 pony engine ?s
""1) Broken starter Brass/bronze terminal protruding out the side of the starter that I believe was the type with a right angled lug to bolt the cable to (lug broken off).
5) A spring loaded "holdin" pushbutton switch near the pony controls which has one terminal grounded... and the other coming from the vacinity of the mag (small gage wire). I assume this to be a mag ground/stop switch... for the pony.""

This is indeed what you say, a Mag stop switch, but it originally was the starter button for a relay that was between the battery cable and the terminal on the starter you repaired. That was connected with a solid copper strap. The other option as was mentioned and you proposed is a high amperage manual pushbutton that also fastened onto the starter. Either one would support the battery cable and since they mount firmly to the starter case, should keep your delicate terminal repair going for a long long time. I would guess the relay is more commonly available than the manual switch.

""2) A single wire from the regulator coming around the back of the main engine and not connected to anything... but does have an eye connetor. Lug on the regulator is unreadable... I also do not understnd how these old box sytle regulators are wired either. Really do need to figure that out someday...""

If you consider the generator and regulator together as one unit, there's only one wire to the machine, the wire from the regulator BAT terminal to the battery. This wire would have been attached to the ammeter on the battery box and another shorter wire from the other side of the ammeter to the battery post. You can do without the ammeter unless you just want one and just connect the wire to the battery cable. If you have an ammeter, any electrical loads like lights etc should be connected on the regulator side of the ammeter, not the battery side. This will make the ammeter show only battery charging/discharging amps, not total generator output.

Removing the screws in the lugs on the regulator will uncover the label stamped into the terminal, but usually the BAT is on the left, GEN or ARM in the center and FLD (field) on the right. The generator terminals should be labeled Field and Armature on the case next to the studs.

""Oh and another quick question.... I assume the small valve on the lower left side of the pony's block( not the head) (as one stands next to the cat to operate the pony engagement) is the fuel shutoff for the pony?""

Yes, that's right. Like SJ says, turn off the fuel and let it run dry to stop the engine. No real need for a mag kill switch on a pony motor, but CAT had a "twist" on/off switch on all of them. Just something to forget to turn on in my opinion.

D2-5J's, D6-9U's, D318 and D333 power units, 12E-99E grader, 922B & 944A wheel loaders, D330C generator set, DW20 water tanker and a bunch of Jersey cows to take care of in my spare time:D

Please Log in or Create an account to join the conversation.

16 years 7 months ago #9336 by dem45133
Replied by dem45133 on topic D4 pony engine ?s
You all are wonderful!

Thank you Tom... I have two old tractors set up that way already, but really would like to have as original someday (if I can ever find a 6 vt battery that will last more than 6 months).

Thank you Old Magnet... these diagrams are exactly what I needed. Actually, the other day while my wife had to go to town for something, I had her stop at NAPA for a switch and plugs... just gave her "1950 Catapiller D4 pony motor". Don't know what their book said but she came home with a regular starter solenoid relay switch and some plugs with the 14 mm base (think this has the bigger 21 mm or so, like the old Farmall 560 had)... although he told her that the book "might be right... might not".

So I think I'll dispence with the "mag ground" reuse the switch to operate the solenoid.... well maybe.... just thought about that if the generator proves good, this may not work with 6vt ... will it? (box doesn't say one way or the other... just looked... only says not to use it with a "computer controlled vehilcle"... don't think I have to worry about that!) Well maybe I'll just go get the heavy switch anyway... I know it will work either way.

Thank you ccJersey. It sure is great when someone knows what something is supposed to be... rather than what sombody did with it. As I said above... if the generator is good, I'll set it up as original. Jerseys... nice high butterfat breed. My personal favorite is a toss up between Gurnseys and Arshires... but then I've milked a lot Holsteins too (do Holsteins really produce real milk... a little thin isn't it? Just harrassing any Hoilstein producers out there... they WILL produce the poundage though. Wasn't raised in dairy (grain and beef actually) but I helped put myself through college by milking twice a day on two area farms 6 1/2 days a week. I'd have 85+- head millked and the parler cleaned and the washer running and still have time to shower and make my 8 am classes... used to just laugh at those that were moaning over being up so early for an 8 am class... I was chasing the cows up at 4:30. They just couldn't relate to that. But then I had to be in bed by 10... not partying to 2 or 3 am... although on occasion I still would and I'd still be in the barn at 4:30, albeit sometimes with a headache. Ah to be that young again... probably kill me now (not the milking... the partying)! Probably don't really need to worry about it... likely couldn't stay awake that long anyway... even if I did try.

Again thanks to all.... will let you know how it goes.

Dave Mikkelson
Hillsboro, OH

Please Log in or Create an account to join the conversation.

Time to create page: 0.143 seconds
Go to top