Hi All, Im after a bit of advice. Today was the first try of starting my 1956 D46U. I have had it for about a year now and slowly chipping away at it. So far I have rebuilt the carby of the pony engine but not yet fitted it back on and got it going. I have drained/changed oils, water, fuel to most of the dozer. I recently installed a 12 volt starter motor (as per the info in this forum) with 2 x 12 heavy duty batteries in parallel. Today I span her over for about 30 seconds with the decompression lever pulled and then engaged. I was surprised by the speed of the motor turning over. I got puffs of blue smoke from the exhaust for about 20 seconds then it sounded like the pony motor engaged and that slowed the main engine right down. The pinion clutch/brake lever and the pinion engagement lever have no resistance in either direction. I watched the Swatch253 YouTube video on starting and I wasn’t sure that was right so I shut her down. There was no fuel pressure but I didn’t expect it to as the fuel tank has been drained and the lines would be full of air. What I am worried about is that the pony motor spinning over with the main motor and there is something wrong with the starting pinion. I’ve watched Swatch253 video’s but still not sure. Does anyone have any idea what may be causing that? Cheers Anthony 

Hi Neil,
Thanks for your reply
Now that you have explained it, I may have used the pinion engagement lever erroneously. (Rookie error)
Is there a way to disengage the pinion gear to disconnect the Pony from the main engine?
Cheers
Anthony

Your post seems confusing to myself. It almost sounds like you have equipped your tractor with direct electric start also? Why the need for 2 12V batteries?
Did you mean the pony is spinning fast, or the main?
Clarification please? It would help some here offering advice. Thanks. JM

Hi JM,
Thanks for your reply. Yes it was a bit confusing, so I went back in and edited it to try and clear up a few points. 
Please excuse my lack of knowledge re-all things caterpillar. I am just starting out on this journey.
I am still working on the pony motor side of things, but it’s not running yet. So, in the meantime I fitted an electric starter to the main engine. I operated the pinion engagement lever which I shouldn’t have done so because I just wanted the main engine to turn over, not the pony motor. Neil has put me on the right track. Hope that makes a bit more sense now.  

Hi Neil,
As we say in Australia, “You bloody beauty” 
I remove the small oval cover as you said, and with much tongue poking and body twisting, I got the pinion to disengage. I then used a bit of Aerostart up the air cleaner, and after god know how many years of not running, it burst into life! It caught us totally by surprise! So a big thank you from down under. We now have a running main engine. We monitored the oil, fuel pressure and water temp and all looked good. Only the beginning I know, but the smiles on our faces this afternoon said it all. 😊
 

Hahaha Anthony, no worries, the excitement from a kitty showing signs of life can be overwhelming! Yes, sounds like the pony pinion is stuck, as per others, go into the round inspection cover and look, or maybe even the larger rectangular one for the clutch. Take a good light to it and see if you can lube it, and give it a whack with a long drift to get it to slide back and forth, after releasing it of course.
Some of us like having "dual starting" capability, and I have known some to bypass the pony due to issues costing too much $ to repair, etc.
Hope to see it barking soon, best of luck! JM