Caterpillar "Pony Motor" - Can Just The Starting Engine Power The Whole Machine? Let's Find Out...

Let's see if we can still drive the tractor with just the pony motor running!

[@d4v3tm]

unfortunately the starting engine only going to last 35 more years instead of 40

[@millomweb]

@@squatch253 What's the cooling arrangement for it ? As I see it, that'd be the biggest issue. Having said that, I'd expect it to share coolant with the main engine - to help warm that up - in which case, no issue !

[@robertquast9684]

The old pony didn’t even complain. At least you know it can be done if needed

[@jbj27406]

And he used the best, least taxing technique to do it.

[@ronford3579]

Can I put 24 volt starter on my dr6 ?? Don't have pony motor..having hard time finding pony motor .....

[@catskinner7564]

@@ronford3579 i sorry this is a year later but you can do it

[@nschlaak]

Color me impressed. I'm a retired wrench who played with the equipment that came many years after these beauties had their day. I found this video to have answered questions that I didn't even know that I had.

[@humancattoy7767]

That's phenomenal. Impressive. The pony motor has a lot of potential. It makes perfect sense as an emergency stopgap.

[@mikegmdw1]

really good to see someone who keeps his equipment clean and treats it well. So many on KZbin start with dirty equipment and don't clean it or blow it off with an air line first.

[@JohnSmith-ef8nr]

That's what she said

[@mikekelly7038]

My dad and grandfather both worked for Fabick Cat for 40 plus years. It was common practice to load a broken machine on trailer with the pony motor moter.

[@garyharper2992]

Not long out of high school, I worked on a pipeline as a swamper on a D-7 Cat that had a pony motor that I had to start each morning. It could be a bear in cold weather. It had a cable lift blade that operated from a front end PTO winch that had a clutch system in front of the radiator and a heavy duty winch on the rear. The operator that ran it only had one arm. There was no power assist on anything on that tractor, he had amazing skills.

[@kevinoscarson2941]

I knew it!!! First hybrid of its day. Diesel for the big work, gas for the travel. Thank you for doing this.

[@JasperFromMS]

This is awesome! It confirms a story that I'd heard when I was a young police officer in Oxford, MS in the late 1980s. There was a riot at the University of MS. There was some construction of campus and a D6 (the person who told me would have known) parked in front of the Law School. Someone cranked the pony motor during the riot and put it in gear without starting the diesel. The dozer climbed into the steps but didn't make it and farther.

[@vanislescotty]

Loved this. This was your idea of abusing an engine. Every engine everywhere is saying, "Why can't this guy own me?"

[@wildcoyote34]

that's very enlightening I would have never thought the starting engine would have enough power to move the machine , let alone climb a hill in any gear ,,you gave me a new appreciation of american engineering with these old machines

[@millomweb]

It's all in the gearing !

[@K5ALLEN]

I remember watching my grandpa loading an old cat dozer with just the pony engine. It can be done!

[@darrenblattner2508]

My Dad bought a D4 about 40 years ago. It was cold when they went to get it and the diesel wouldn't start so they loaded it on the truck with the starter motor. I figured yours would do the same. Thanks for the videos, always a please to watch. Keep smiling.

[@Wydglide]

Love the video im 57 and a little D6 is what i learned on at age 8 that engine sound REALLY brings back old Memories! 🕶👍🇺🇸

[@dozerboy67]

This video took me back to my childhood. My father used to send me out at 4am to fire off our old cable rigged D6. Sometimes when it was cold it would take me five or six tries to fire off the diesel. Some people have no idea just how nice it is to sit in that cab and turn the key. Thanks for the trip down memory lane! 👍💪🤟🤙👊

[@cassiuspuckett8789]

Well, I thought it would do it, because I've move fully loaded semi- trucks with just the electric starter motors when my clutch went out and couldn't release the clutch. It's not a recommended practice because it is so hard on the starter motor, but it can be done. Thanks for sharing....

[@mfreund15448]

Drove all day picking up milk from farms shutting off the truck and putting in reverse and starting it back up when the clutch fork broke.

[@MindBlowerWTF]

I abused few starters and they were fine, while my friend tried it once and it ripped out a bit of the bellhousing. Whoops

[@mfree80286]

Had a dodge shadow once that for whatever reason the clutch interlock wasn't... there, actually, not even any wiring. Not an issue for years until one day I hopped in, hit the starter and the damn thing took off like a rocket; I'd left it in second gear. Light little car doesn't need much!

[@millomweb]

@@mfreund15448 I don't know why the OP didn't use the engine like you and I. I've driven a vehicle 30-odd miles without a clutch pedal - going through the gears fairly normally. I've even driven a tractor a couple of miles without the steering wheel making any difference !

[@jazzerbyte]

I "heard" the timing problem - thanks for the explanation at the end!

[@lukestrasser]

I am glad I watched to the end before leaving the "I think your timing might have been too far advanced" comment. You're pretty sharp, I don't care what Rick says!

[@jbj27406]

Yeah, that was the only time when I thought any damage was imminent, but he got right off of it.

[@BarnyardEngineering]

That was just a good breakin session for the little guy. Rings are nice and seated now.

[@KennyKizzleRustyNutzRanch]

Pretty cool that the little guy has enough power. If ever in a tight spot, now we know! Thanks for the video, Squatch.

[@clydebalcom8252]

Okay. In an emergency it's feasible. I'm impressed. I really appreciate it when you answer our questions.

[@jamesplotkin4674]

You may have lost 5 years' life, but I can see this beast running fine in the year 2075 ;-)

[@lifebehindacow5999]

Great video. My uncle farmed with an RD6 most of his life. He and my Dad harvested wheat together when I was growing up. You just brought back a bunch memories of him firing up that tractor and pulling into the wheat with his 51 International combine in tow.

[@juantransportador]

Hello from las vegas Nevada, I'm a new subscriber and I love old machines, I'm lucky to find your chanel, GOD BLESS YOU AND YOUR FAMILY,

[@shawngleason1345]

Thumbs up for your video. You'd almost think it was designed like that for emergency use but with most diesel failures you wouldn't be able to spin the engine

[@jdm2651]

Really liked this episode. You did something different, even a bit unorthodox, beside answering the question that was another good chance to see around your beautiful property.

[@frritter8253]

Fun experiment, thanks for taking us along Toby! Nice fall day in your trees.

[@fbh31118]

Your nicer than I am, I don't think I would have pushed it that far. LOL! Very good demonstration of what that Cat and its starting motor will do. Thank you for sharing with us. Love your content.

[@altonriggs2352]

Don't let Senior catch you doing that!

[@joeromanak8797]

My first thought was you could crank an old pickup truck across the backyard with the starter but the equipment ain’t gonna like it. The old RD did much better than I was expecting. I was worried at the end when you came back on and said you heard funny pops on the hill. I thought you were going to say something broke. Glad it wasn’t that. Keep em chugging! 😎👍

[@jimturpin]

I had heard of pony motors as a kid, probably even saw a few without even knowing it. Thanks for sharing this, frankly I thought it was cool as heck to have a "dual" engine dozer, and now you know you have a plan "B" if the main engine quits. Lol!

[@rogercarrico4975]

Very interesting. I love anything to do with those ole tractors! Thanks for posting😊👍

[@keithross4511]

I had a D6 that is a 4R series, with the opposed 2 cyl pony motor, and have moved that tractor. So you bet that little engine will do the job. I sold my D6 in September of1987 to have money to go to aviation school. Over the years, I lost track of where my old D6 an 4R1788 went, and so often wondered what became of it, scraped out and long gone to the junk pile, or been torched and melted down. Five years ago, I found it! Sitting in some woods on a farm, like a long lost friend! I’m going to buy that tractor back and restore it!

[@millomweb]

I'm a bit pleased to see the donkey engine not screaming its head off too. So many videos I see them screaming. Get it warmed up, it'll have more power than normally used for starting the main engine.

[@chrismaurer8879]

I like how you respond to the questions thank you its a joy to watch your chanel

[@mikeyoungblood1706]

On a South Florida vegetable farm Dad had two of these RD-6 Tractors , I must have put half a million miles on them, Does My heart good to see what You have done with this one.

[@ryansmifh]

this is what no one expected but everyone wanted!

[@TheAmazingAdventuresOfMiles]

Great Video, I enjoyed that. Reminds me of the time I had to move my Land Rover about a mile using just the starter motor. It went surprisingly well with the four spark plugs removed so no compression, the transfer box in low range and just done in stages to let the motor cool down. I had a small 12v generator running in the load bay keeping the battery charged. Took a while but it sure beat pushing it!

[@millomweb]

What was the output current of the generator ? Why would the engine start? #epic_journey ! Reminds me of a journey in an early Landy towing something up a hill - at a speed where I started counting the white centre lines on the road !

[@robertdavis6708]

Love your dozer sir. My favorite machine was the Cat 955, used many many years. Yours's has a strong pony motor, as they'll last for years if taken care of.

[@ojjenkins7110]

Great video. Best one of a CAT I have ever seen. I never thought of having to do that, thanks :-)

[@paulmartin8212]

that was fun. I'll bet you already knew the capability? Love your channel and just the love you and your dad have for these old machines and keeping them going.

[@bcbloc02]

I used to win the slow races at the dairy festival by running my 820 Deere around with the pony motor. 😎

[@eightycubicft]

I've always been impressed with you guy's working on big constitution equipment. I have some experience in this field but didn't explore my talents. I work with crain's on the pill end of them.i got in the seat of crain's to early in life, young and board. Anyway, good work I enjoyed the video. Thanks please share some more.

[@Mighty-Quinn]

Well color me impressed, I didn't think it would move it at all, let alone move up a hill! I'm glad you were bold enough to test this theory out an answer a question we've all had. Although, I wouldn't want to do this to my D4......

[@andygotting9152]

I was half expecting senior to come out and tear you a new one.

[@paulcopeland9035]

Why? If it breaks, you know who will fix it.

[@ianrutherford878]

My reservations about this would not be on the life-expectancy of the pony, but the little straight-cut pinion gear and whatever bushes (English)/bushings it runs on.But maybe that gentle clutch start /4th gear run/ climb puts no more load on them than a cold diesel engine with optimal compression and the decompressor closed ,but with starting problems.

[@mohabatkhanmalak1161]

I think the pony motor was made for a limited life before overhaul. I am pretty sure Cat made them for hauling the machine up the ramp of a loader. It would be in the operators manual.

[@larrytomb3896]

Worked on dozers (D9 serial 66A12576) used in strip mines in the 70'0 had poney motors. In fact as far as i remember all 9G's could be speced with pony motors.

[@shadowbanned69]

Dear heavens man....don’t try it again....you def made your point! If you go and break something and it’s not fixable..than what... It did a awesome job..... far exceeded expectations Shut her on down and keep her happy Awesome real world test tho!

[@carlthor91]

I would have messaged to those that wanted this to take a hike. I have also been accused of not playing well with others. Best wishes, stay safe

[@SuperMAZ007]

That was one awesome but fun test. Something good to know if anything else fails the pony engine will help you out.

[@tiredoldmechanic1791]

I often wished some of the new machinery had pony motors. They don't even have a clutch on the hydraulic pump so they turn everything when trying to start. They have to be parked inside when it's cold.

[@SouthernMechanic]

I dont know if this story is true but I used to be a mechanic for caterpillar years ago and I heard a story of a guy that was hired on by a coal company and he claimed to have more experience operating a dozer than he said he did so he got hired and they gave him a job to do with a cat dozer, they dropped him off and told him what to do, he came back a little while later complaining that the dozer didnt have any power so the boss goes out to the dozer and fires up the pony engine then starts the diesel and starts pushing, the new guy has a very puzzled look on his face, when the boss man shuts the machine down and comes over to the new guy the boss man soon finds out that the new guy had fired up the pony engine and engaged the drive and was trying to run the machine and push dirt with the pony engine 😅

[@SootHead]

The burning question of the last century and this one. Answered by the Squatch!

[@jbj27406]

I hope your father doesn't find out about this, young man! These kids today. What are you going to do with them?

[@soundadvicesomewhere9027]

Great to see this video & the care & explaining you did to keep the pony motor protected! LUV ur site & absorbing the knowledge found here - Toby. Really Thanks 🙏!!

[@littlejason99]

I would have suspected it would have moved before seeing the video. Like someone else commented, people have moved vehicles with just a starter motor. It's all about the gear reduction!

[@karenseibertyourshowes7397]

“L

[@zfine1450]

Had an 86 Toyota 4x4 that had a "crawl" button to engage the starter without starting the engine so you didn't have to burn the clutch.

[@millomweb]

@@zfine1450 What's the clutch got to do with it ?

[@francistheodorecatte]

with enough gearing, you can move anything with 24hp. 🤔

[@francistheodorecatte]

I need a 10 hour long ASMR audio clip of that RD6 idling btw.

[@paulsilva3346]

So why prove it?.?

[@Synergy7Studios]

I've seen gearboxes made with cheap 3d printers be used to lift anvils. They just connected gear after gear, so the ratio was absurd and the weak teeth distributed the force accross a large surface area.

[@paulsilva3346]

@TRUMP TARD We all have those regrets, now. Thanks.

[@benjigray8690]

@TRUMP TARD I saw a four page story about it in Nat. Geo, or some other magazine years ago, an amazing feat, It showed what can be done when you put folks that know what they are doing in charge. I remember the bloke in charge had a white resistall hard hat. Erosion was the reason for shifting that light house?

[@somerandomguy3868]

Really didn't surprise me on the flat, on that incline that's a different thing all together, you're probably right about the spark advance but I wouldn't do it again, you know you'd feel terrible if anything happens to the start engine, thanks for doing it I've wondered about that myself, at the end of the day I think it was designed to be able to do that in an emergency situation

[@waltermattson5566]

Thanks for the video. I have always wondered about this test.

[@elricm13]

Great video! I run my JD diesel tractors on their pony’s when I just want to move them and I don’t have time to keep the diesel running. Always surprising how tough those little pony’s are.

[@scotte2815]

color me impressed! 24 HP is 24 HP but 16K lbs is 16K lbs yep, that was fun to watch

[@huseyinuguralacatli5064]

my car is 26hp (1280lbs empty weight) but it struggles at hills with 4 person on it. it's all about gearing!

[@davidcampbell1306]

My dad was a Seabee stationed in Guam during the Korean conflict, (50s). He was a mechanic and said the operators used to bring the dozers in all the time on the pony motors when the diesels broke down and the mechanics would move them around in the shop area with the pony motors. As far as I remember I never heard him talking about having to repair a pony motor but heard plenty about the diesels breaking down.

[@Skoda130]

It's still good to know, that in case of an emergency, you could still use it to move the thing.

[@peterranger7276]

Yes they are capable of loading machine onto a trailer, have done it with a D7 17a also have heard some of the old timers used them to get out of a bog.

[@rjmittleider5011]

I had a boat with a d 4 cat and pony. We had fuel problems constantly la light san Pedro I went down and started the pony my wife drove the boat to a mooring ball while I stood watch on the pinion . Motor was a 1927 x built 7/18/27 .

[@AmericanMan530]

Love the antique cat equipment!

[@timd1965]

Those CAT's are some amazing machines. To be able to move it in a emergancy with the starting motor is good to know. I'm sure CAT would likely frown on using the starter motor like that. Cool video though!

[@tpniefer]

Funny thing how answering one question always leads to many more. Great video though, Squatch.

[@scotte2815]

OK @0:50 STOP RIGHT THERE! DROP EVERY THING! tell us about that blue Chevy truck please, and AND can that be your next project?

[@millomweb]

5:00 - so if normal engine rpm is 1,000 and the donkey engine drives the main engine at 100 rpm, that's 10:1. If the gear ratio of 1st gear is 10:1 too then, driven by the donkey engine, an hour's work would take upwards of 100 hours to complete ! I did expect it to do all it would with the main engine power - but ever so slowly !

[@TheRonnyL]

That was kind of unexpected 😊 Impressive! Cool video!

[@mikebaldwin9972]

Now I’ve seen a Proud Pecock with its Clydesdale doing their THING,THANK YOU SIR once AGAIN!!!!!!!!

[@111000100101001]

Ah that pony just seated its rings :) Great video!

[@davidkimmel4216]

Thank you. Good explanation

[@lbbradley55]

My father was a heavy equipment operator Army Corp of engineers during the Korean war he helped build runways in England. He told us about cranking his Cats D-7 & D-8 with these pony motors. I never heard him mention this however and I wish he was here I would certainly show him this. Interesting

[@patzke]

I walked a D8 cat using it’s pony motor and loaded it onto the trailer to take it to the Cat dealer for diesel repair. This was a late 1960s Cat.

[@swagmanexplores7472]

"Someday" 😊

[@caerusdharken57]

The little engine that could :) I was pretty sure it would move at least in the low gears after I saw you move that mothball unit (don't recall which one it was) by turning the whole engine and drivetrain with the crank handle.

[@wesreeder6721]

15 HRS pony engine Moving 8 tons of cat. AMAZING. Wonder what briggs & Stratton is thinking now. I got a 13 HRS on my bandsaw mill. No log has ever stalled it. YET. LOL. Good video.

[@MoparNewport]

Seriously impressive, even when keeping in mind the monster gear reduction that the lil pony has to work with. Nicely done! Whatd the oil look like after that pull?

[@millomweb]

7:00 From what I've just seen, I'd expect it to get up that hill in 4th.

[@l0jack]

I actually successfully attempted this with our 1951 D2 many years ago, but I only used first gear and only moved it around 10 feet.

[@clinthowe7629]

It’s so weird, I had a cat just like that, except mine was called a D6, not an RD6. it had an enormous blade that i switched out with a smaller one off a parts cat we picked up that we used also for the track frames, it was a good little pusher, I sold it on eBay of all things to a guy in Canada who had a company named James Dick Construction, i think he bought it for yard art or to restore. i hope he took care of it.

[@alistairgrant4844]

I was told by an old operator he's got a d6 stuck a few times he would start the pony put it in low gear and go to lunch while it crawled out ,hope it raises your eye brows as much as it did mine

[@hiyadroogs]

This all makes sense, actually. The diesel is rated at 52 bhp @ 750 rpm. Or 364 ft/lbs. The pony engine is 24 bhp @ 2700. Or 46.7 ft/lbs. So, the pony engine develops 46% of the horsepower of the diesel at 3.6 times the rpm. Effectively, the pony engine develops 12.83% of the torque of the diesel at the pony engine's crankshaft. Given the ratio of the pony engine's starter pinion, & the ring gear around the diesel's flywheel, which is probably around 40:1, then moving the dozer in low gears & light load isn't too difficult.

[@charlescartwright6367]

Aloha I knew it would as I have done it. My dad who was a seabee in ww2 said this was common practice in getting a tractor unstuck, he said they could let it crawl out on the pony motor when the main engine would just spin the tracks.

[@regsparkes6507]

I wondered about this many ears ago,..."is the Pony Motor capable of driving this tractor?" Thanks for showing us this, that it can,...it is interesting.

[@pnwRC.]

Cool video! I had frequently wondered if this was a possibility!

[@robertmukaida5408]

I love the old cat crallers and the other two as well

[@mohabatkhanmalak1161]

Image a scenario where the main diesel broke down, and they had to drive it up on a loader. This is where the pony motor would come to the rescue!

[@DavidWright-yh8zx]

Impressive exhibition !!.

[@bitsnpieces11]

Something like that happened to me at a stop light. My car, manual trans, died and wouldn't restart, I had to use the starter to pull it to the side of the road so I could tinker on it.

[@WhitfieldProductionsTV]

Talked to my grandpa about this, since I know he's into cats, he say's when they were building out the highway system, they would do this when it was cold, get them moving about so the temps came up quicker.

[@donbullock8790]

When I was in the Army we had the old D-8's with the pony motor. They were different from yours, you had to crank them from the side. One knee on the track and watch that thumb, HA HA. I always enjoy your videos. Keep them coming.

[@bitsnpieces11]

I tend to think of these engines on the Cats building the Alaska highway during winter, when they had to turn the main engine for a considerable time to get it warm enough to actually start and run in the mornings.

[@robertboyd3863]

They seldom ever shut a engine down

[@garyb5796]

Excellent, Very Impressive Machine!! I agree with you about the Timing and Hill Climb the way it was popping, if it was fuel it would gradually slow down even running at full throttle. The popping is from the unburnt fuel in the exhaust from the misfire, timing. Both engines sound Excellent Running, the crispness in the diesel engine Very Nice!! This test also proved how good the hydraulic system, I was thinking there wouldn't be enough RPMs to run the hydraulics, it did steering and all!! Thank You For Sharing!!! Liked, Sub & Notified

[@mfree80286]

Heh, right before you started that hill I thought I heard the pony clattering.... and realized it's the rain cap. EDIT: I was thinking less of timing and more of the carb not being jetted for that much load and going lean, the way it was popping. I don't know how much timing's available on that setup though, could very well be overly advanced for the load, or both situations.

[@GarnettM]

I`ve never tried that either ! Have you seen Buddy that got that old D6 Bucket Cat OLD RED ,Wow he took on a fix but it fired up

[@GarnettM]

@Jambo Off hand I thought it was a 6 , Still good project has enough parts to fix it to good conditon again I think .

[@Ham68229]

My first initial answer is/was, yes. For the simple reason, you're turning the diesel engine over hence, turning the clutch(s) and transmission gears. Only other concern of doing this is, the injector pump on the diesel, it's turning without any fuel being pumped through it. Last I knew, injector pumps used the fuel oil as lubricant. This isn't recommended from Cat if I remember correctly, I could be wrong. For those saying proper gearing, yes, absolutely correct. Look at John Deere's 2 cylinder tractors, it's how they're designed. You thought process might be spot on but, how much gas is in the tank for that starter engine? My old JD "B" acts like that on an incline when the tank is starting to get low on gas. Great video, cheers :)

[@bobpaterson1845]

Brilliant video 👍 that's quite an achievement that pony motor powerin that Cat 💪💪

[@doctorcountersteer6580]

Understandably we are a curious species that hungers for knowledge and I appreciate your time in this vid, but, no, it wont; not effectively. If that were the case it wouldn't have warranted Kitty installing that iconic, *unparalleled* power plant forward of the clutch assembly in the first place.