Hey guys,
I have a D-47u that I need to know if I can adjust the pony motor starter pinion latches on, without alot of disassembly. The pinion control lever has to be held up to stay engaged. The clutch seems to operate properly, it pops overcenter like it is supposed to. The pinion just won't stay engaged. I don't release the pinion control lever until I have overcentered the clutch lever. I have the Cat diesel engines service manual for the D-4 and it looks to me like the clutch and starter pinion assembly needs to be removed from the diesel engine flywheel housing to adjust the pinion latches. To do that, it sounds like you have to almost remove the pony motor, drain the cooling system. {pages 275 to 281} Sounds like a pain. I was wondering if there is any other way to get the latch adjustment done. I also need to know how to adjust the latches. {I assume that is my problem} How do you know when they are adjusted properly? Do you have to reassemble it all and test and if not right do it all again? Also [page 280] "if disengageing speed is raised too high, damage to starting engine can result if the engine is overspeeded." How do I avoid that? I can run this the way it is, I just would rather it work correctly, if it's not alot of work, or expensive. I posted a couple of questions re- flywheel clutch adjustment, and a steering linkage part, {last summer} the answers were very helpful. {Thanks again guys!} I am still working on getting this going. I assume that when I get the diesel started the way this is, I will have to be careful when the pinion kicks out since I have to hold the lever up. {that my hand doesn't get yanked, and also that the pinion does indeed kick out when the diesel starts.} When I started working on this, the flywheel clutch would not overcenter {you had to hold it engaged. I got that adjusted properly}, the throttle and choke on the pony motor would not stay in place, you had to hold them {the bracket has a spring and two buttons inside it that hold tension on the linkages so they stay in place. I fixed that} The starter pinion lever has to be held up to stay engaged. The steering control levers have to be pulled almost to your lap to steer.{ I will probably have to live with that for now. It is a steering linkage part [the "cranks". see my post "steering clutches, need linkage part" of Oct 07.] I don't think they are available, and to repair them [or replace] the trans. cover has to come off} I am new to running this, it is already a multiple step job to start the diesel. I am trying to get this so I don't need 4 hands to start and run this thing. I am also having my usual problems with the carb on the pony motor. The float {only 2 years old} was decomposing {leaving little pieces of it in the float bowl}, the needle and seat were sticking {they always do, I don't know if it causes a problem but whenever I have problems with the carb I replace them.} I sprayed the carb with gumout and blew it out good with compressed air and replaced it, it runs for awhile {4 or 5 minutes} then quits. {I had the old float and needle and seat, I reinstalled them, the old float looked fine, and same problem.} I am going to soak it in carb cleaner, run wire through whatever passages I can, blow it out again, replace the float and needle and seat, and put in a new inline fuel filter. {there is a inline filter added between the "starting engine sediment bowl filter" and the carb.} It puts a loop of hose in the gravity feed that I don't like. I see in the book {page 69} that there is a "edge type filter" in the sediment bowl, if so, I may take the inline filter and loop of hose out. { it seems like the pony motor tank needs to be full for gas to flow right.} When the pony motor quits the spark plugs are dry, so I assume that I either have a dirt or clog problem somewhere, or the needle and seat were sticking. I really don't think it is the gravity feed as long as the gas tank is full, but I want to eliminate that possibility. When it quits, I take off the float bowl lid, you can't really tell if it was empty because as soon as you lift the lid gas comes out when the float drops, so I don't think the gravity feed is the problem. I have rapped on the bowl to try to unstick the needle and seat in case that was the problem, and no start. After I replace the bowl lid, {with gas now in the bowl} it still won't start. So I really think I have a clog problem. I checked my records for part numbers when I bought the new float, and needle and seat, and found that I replaced both of these in 98 and in 06. So either that or a good carb cleaning usually does the job. {when I have this problem the gas is ALWAYS bad. Smells like varnish. I empty the gas tank, but I have not tried to clean it. It is real rusty, I was afraid I'd put more rust into the system if I cleaned it. I have been counting on the inline filter {clean, it never looks dirty at all}, but maybe it lets some real small stuff through. I may need to try to clean the tank. I will also pay more attention to cleaning the copper fuel line {remember it has been cut, and a loop of hose and a inline filter added} Anyway, sorry about the long post, I figured the more info the better. Any help is really appreciated.
Frank Lyons

P.S. In the starting instructions for this {Cat D-4 operation and maintainence manual, page33 #8} it says after starting the diesel to shut off the gas to the pony motor and let it run out of gas, then turn ignition off. That is when these were new, so I figure that the carb design on these was not so hot from day one. I usually run it out of gas every time I am done working on it, but I think it still leaves enough gas in the carb to cause clogging by the next season. If you have the D-4 service manual for diesel engines on page 283, I believe that the areas that get clogged are the "compensator passage" #8, in the bottom of the float bowl, and maybe the idle discharge jet #4 {the long tube that screws in from the outside of the throttle bore of the carb into the bowl.} , and on page 282 the main passage #11. The jets, {main jet and compensator jet are easy to see if they are clean.

Frank,
To adjust the pinion release speed, take off the little cover on the flywheel housing that covers the end of the pinion. You'll have to take the left floorboard off first. When you get that little cover off, you'll be looking at the latch end of the pinion. Remove the cotter pin that's in the slot of the screw, turn the screw in a turn, replace the cotter pin and do the same thing to the other screw. Start the pony and try to start the main. .if it kicks out like it should, that's been cured. If not, adjust another full turn and try it again.

Pony carb, the perennial problem. There have been threads on here and ACME about 'em. I'll tell ya right off that just soaking it in cleaner and blowing everything out probably won't do it. You'll need to drill the little plugs out to really clean all the passages. I used a .171" drill to get 'em out and after I was satisfied that everything was clean I tapped a BB into the drilled out holes and "swiped" a dab of silicone over 'em. The float coming apart can be cured by mixing up some fiberglass epoxy and painting it on. The best bet is to use different gas, one that doesn't have alcohol in it . .if you can find it. Aviation gas comes to mind there. .it's not that much more expensive than regular gas for no more than you'll need. Also, check that the float drops and doesn't stick before you put the lid back on the carb. I had to adjust the tang that stops the drop on one of mine. .someone tried to "lean" the carb out with the float and it barely dropped at all. After I bent the tang so the float would drop about 1/2", everything was fine again.

Steering clutches. .if you can't get the adjustment right (2-3" of free travel at the top of the levers) you may have badly worn clutches that need rebuilt. If so, the lid needs to come off and while it's off, check the bearings in the ends of the cranks. They're probably worn and rusted out to the point of needing replacement. Any slack anywhere in the steering clutch linkage will add up and that in turn messes up the adjustment.