Also note the crank gear is keyed to the shaft and has timing marks to avoid installing it 180 off. It is then possible to remove the bolts, lock, and washer from the crank gear and use a puller with a couple of good quality 1/4"x20 bolts in the provided holes. You can then remove the idler gear, and unbolt the rod caps and remove the pistons. Tappets come out next followed by front cover, then camshaft. Then remove the roundish rear cover from behind flywheel and both cylinder heads, then valve and guide assemblies by removing the retainer forks that locate them in the block. Basic disassembly includes removing pony from Diesel engine, taking the top manifold off, then pulling the flywheel off the crank with a good puller (if taps with a hammer are necessary, do not strike the puller screw or face of flywheel, rather tap radially around the outside of flywheel to avoid damaging the crankshaft). The idler gear that sticks out the bottom of the pony is the only one not timed. Yep, crank gear drives the cam gear, and cam gear drives the mag gear, and there's timing marks for all of them. And yes, if one main bearing is replaced, the other one must be renewed as well or you'll risk breaking the crankshaft, their hollow rod journal design is a weak spot. Cat still stocks the locating dowel, and it is good practice to replace it every time a new bearing is put in.
1959 CAT D2 DOZER SPECS CRACKED
Sometimes you'll also find that the upper portion of the block bore is cracked between the 2 oil holes and dowel hole, which will then require a good retaining compound to also be used to keep the new bearing tight.
Excessive endplay almost always indicates that this dowel has come out of the bearing and the bearing has spun in the block bore and is now floating back and forth. The front bearing (crank gear end) controls the thrust and is retained in the block bore via press fit and a locating dowel. Those pony main bearings are basically T6061 aluminum sleeves and can be made on a lathe with close attention paid to the press fit tolerance. Cat issued a service bulletin about this condition back in the '40's which I have in a book here somewhere - says that when the crankshaft starts floating around it causes erratic vibrations to transmit through the cam gear then into the mag gear, and the mag being the weakest component in the gear train always suffers the damage. Back then I used to pull start my D4 with my '53 Ford pickup when the starting engine acted up but then I was sweating all day in case the engine stalled at a bad moment.Ībout the only things I can add that haven't already been said is that excessive endplay and radial clearance on those D2/D4 pony cranks will cause mag gear breakage and usually also bend the magneto shaft at the same time. I think you are on the right track, carefully inspect the engine and make it as right as you can to assure dependable service. Bouncing around all day, gas would make its way past the needle and seat and eventually into the crankcase, diluting the oil. Operators would switch off the ignition and, worse yet, leave the valve open on the gas tank. Rather idle it back, close the valve at the gas tank and let the engine run the carburetor dry. That is, when the diesel starts, do not shut off the starting engine.
1959 CAT D2 DOZER SPECS MANUAL
These things were rarely maintained, and only got attention when they gave trouble, and then only got minimal repairs, enough to get the machine going again.īut the true root cause is, operators did not follow the operating manual instructions for starting. There are two main reasons why this is true. ".other pony motors laying in the weeds are probably in poor condition." Re: D4 Cat Pony Motor + questions about worn parts Please weigh in with your opinions on the above. That access although possible would be more difficult with the pony installed on the CAT. This procedure could just as well be done with the motor installed at a later
1959 CAT D2 DOZER SPECS INSTALL
The other option would be to install the pony as is and see what happens. Outside surface on the lathe for a press fit and then boring the inside of the Making one with babbitt by making a rough casting and then turning the The bearing if purchased costs about $100 so am considering Thinking it would be prudent to tighten up these tolerances before reinstalling The engine ranįine but was leaking oil because the seal was bad behind the flywheel. On the end of the crank as well which is about 10 thousandths. Another thing I noticed is that one can detect side play I am somewhat concerned about the end play on theįlywheel end of the crankshaft which is somewhere in the neighborhood ofġ00 to 125 thousandths. I have the pony motor removed and the starting pinion and clutch rebuilt and
0 kommentar(er)
