I do not have a Serviceman's Reference Manual for a 12A 955 Traxcavator, although I have a D-4 Crawler Service manual.  I need to take the motor out of the machine to put in new liners, pistons, rings, and bearings.  With the motor removed it can be put on an engine stand and rotated to facilitate installation of new parts and cleaning. I do not consider rebuilding in place as an option because everything is so tight and close that I do not think a good job can be accomplished.  Plus, with the motor out of the machine it can be set up on a stand with a radiator and run for final adjustments.  I have read a post by Bill Glen who removed the oil pan of a 955 for bearing work. He removed the six bolts which holds the frame to the cross member connecting the track frames and the center pivot pin holding the motor to the cross member.  Then he jacked the entire motor and frame up pivoting everything with the oscillation of the track frames, so the oil pan cleared the cross member allowing him to remove the oil pan.  Is there enough room to get the motor and pony motor out of the machine together with it in this position if everything is removed that connects the motor or pony motor to the loader frame?  What I see that needs to be removed is radiator with the hydraulic pump and associated lines, air cleaner intake pipe, entire operator station as stated in the D-4 Crawler Service Manual for wet clutch removal, just don't take the clutch out, clutch to transmission coupler, clutch linkage, Before the bolts holding the clutch housing to the transmission can be removed the transmission and motor needs to be supported in the position, they are in.  I have removed the bucket so the loader arms can be lowered for more room, and motor lifted out with a gantry crane.   Will it work or am I missing something?  Brian Boaz

You really need to get the "Service Information for Caterpillar #955 Traxcavator". It goes way beyond what is available in the D4 version. Lots of things to disconnect, especially in the oil clutch area and yes it describes engine removal.
Not a common manual to find but there must be some out there.

 

Can't say I'd recommend the Jensales repot as you need good picture quality but the ebay item seems to be the correct info.
For unknown reason I am unable to post a link to the ebay item on here.

 

OM: Yes, I am missing the proper manual for this task. Believe me, I have been looking for that manual. I have taken things apart and back together two and three times with everything I have done to this machine when it would have been so simple to read a procedure and follow it one time instead of stumbling in the dark. I have seen the E-bay Jensales book, and I have heard it is not the quality of caterpillar manuals, but it might be better than nothing or the D-4 Manual I have. Old Magnet, would you consider sending me your copy of the Service Information for Caterpillar 955 Traxcavator and let me copy it for a price? I have searched using the form number for the manual and have not found one a one anywhere. I might call Caterpillar tomorrow and see if they can order me one

Let me get the wife's car unstuck (that I got stuck) and I'll see if I can get my printer working... Then I'll see if I can send one your way.
The one I found is not Cat and is a bad service manual so stay with Cat manuals.
My Cat SM is MIA at this second.
it will be back a few hours.

Dan, I have ordered the Jensalesl Service manual from E-bay. Should have it in a couple of days. It may not be the standard that Caterpillar produces but maybe between it and the D-4 book I have but maybe it will be some help. Thanks for making the effort. Find your Cat Manual. Seems it is priceless. Thanks Brian Boaz

For the life of me I cannot find my Cat 955 12A Service Manuals 😱. not even the bad one.😱😱
I had it all typed out earlier but timed out and lost the info.
A few important things that will help with 955 12A
First ......Try to stay with Cat Manuals if at all possible the other aftermarket manuals get a lot of things wrong ....
Case in point ... the aftermarket SM has you taking out the oscillating spring and the track loaders don't have a suspension oscillating spring but has a rigid frame. Note that sometimes the rigid frame is welded to the track frames.🤦
Second... What is your Serial Number ? At 12A5793 the 12A 955C changed degeneration to 955E. Major changes were made to the 955 and the suspension went from D4 to D6. A good Cat service manual will help you sort the changes out.
Third...  If you remove the bucket and bucket arms you will ha much better access the the front. It is very easy to remove the bucket and bucket arms from the rams.
Fourth ... Pull ROPS if you have the opportunity.
Fifth ... when you go to remove the rocker arms "REMOVE THE DECOMPRESSION ROD FIRST." Otherwise you could bend the end of the decompression rod. Yup, Ask me.
Sixth...The "A" frame over the engine IS ALWAYS in the way. If you stand over the "A" frame you will see a 1" hole off center to the right. The hole is for access to remove the two pushrods from cylinder 6.
Seventh... To remove the pinion clutch you will need to remove the pony motor and depending on the model the diesel engine governor (955C). 

I am by no means a Cat mechanic but these are some things I've stubbed my toes on so far.
Good luck . I have a few videos on YouTube of me working on the 955's     search "Fat Dan coming home" will get ya there. just an old retired fart farting around

Thanks Dan:

LOL 6th cylinder.🤦.... I reread that and that's funny😁 ... must have been channeling my D318
the D315 only has 4 Cylinders 🙄