quick background, picked up this D@ 5 years aga as a runner needing work, the pony motor blew the main crank seal, fuel lines leaking and held together by wire, the dozed blade was half off pins missing and front apart, over the years done bits to it and have some fun

when I picked it up the old guy went thro starting and I recall when he fired it up the horizontal engagement lever pulled up had a distinctive click, he then pushed the lever to engage main motor and showed the fuel pressure in green and oil pressure, after a few mins of warmup he threw decompression and gave fuel and off it went.

I have ran it a couple times after doing the work to get hydraulics for blade functioning but only short runs

last night fired the pony, pulled the lever but when I pushed the engagement the lower lever kicked out and motor slowed, tried several times same issue so finally held the lever then pushed engagement and it held, what I noticed no fuel pressure, nothing, anyway let it warm up threw decompression off and gave it throttle and it ran fine.

ran it around for a couple hours in the yard tried pushing no issues other than no fuel pressure on the gauge.
anyone have ideas on both fuel pressure and the engagement lever kicking out, ant guidance would be appreciated

Gauge is bad? Easy enough to get a new one from Cat or knock offs from ebay. It's running so there must be some pressure.
Pinion kicking out is because the fly weights on the pinion need adjusting. They work sorta like a governor.
Check to see if the pinion is rusty dirty etc. There is a screw near the weights that can be turned to adjust them.

can this be done without removing anything? maybe a inspection cover guess I need a manual for this old beast

Congrats on a running machine. If you’re a member. Tech Library will run you through the pinion latch adjustments. Regardless, look on eBay or on here for Operations Manual, Servicemen’s Reference, and parts book. All for your machines serial number. Coincidentally I just fired my pony /main up Sunday after not starting it for two years.

There are several posts about holding the pinion engagement lever (“horizontal”) up while spinning pony under main load. I’ve done it but not recommended. Mine is adjusted until it’s not! Pinion adjustments will hopefully take care of that. Not sure why engine slowed when pinion kicked out…there is an access port to access the latch adjustment screws.

Without manuals and help from individuals from ACMOC and ACME BOARDS, using and working on my D42T would have been a steep climb and likely resulted in tearing up my CAT. FYI my knowledge is / was limited. Yours might be much higher, so pardon any unintended inference.

bernie, the engine slowed when the horizontal lever dropped out, this happened when the engagement lever was pushed forward to spin the motor, hence holding up the lever to keep it engaged.
will look at getting the manual even though I work on lots of vehicles rebuilding and a full machine shop Im no means a expert but enjoy working on old equipment, its been 3 years sibce I fixed the fuel leak, the issue was a cracked fitting, I recall removing a block the fuel lines go into, when taken apart and tapping the block it had springs and balls its possible its not together correctly and could be the issue with the gauge