Bobcat 553 with Kabuta won't start, belches black smoke.

[badsam1957]

I have a 553 with 315 hours on it that won't start, cranks fine and belches black smoke. Worked fine the last time I used it about month ago. I thought it might have a low battery, so I put the charger on it then after the battery was charged switched the charger to the 50 amp setting and tried it again. Same thing; just black smoke but cranked really fast. This is around a 2000 vintage with some electronic controls. I'm wondering if what ever shuts the motor down, might be stuck. It obviously is not a fuel issue considering all the black unburned fuel coming out of the stack, is there an air shut off on this one or a compression release? Thaks in advance for you help! Mike

 

[Tazza]

I'm wondering if your timing is an issue. Can you get a compression tester and hook it up to see if you may even have a stuck valve?

 

[OldMachinist]

I'm wondering if your timing is an issue. Can you get a compression tester and hook it up to see if you may even have a stuck valve?

If it has aux hydraulics controlled by moving the right steering lever make sure they're off.
Check for a air intake restriction, some critter may have built a nest in there.
Verify the glow plugs are getting power.

 

[badsam1957]

If it has aux hydraulics controlled by moving the right steering lever make sure they're off.
Check for a air intake restriction, some critter may have built a nest in there.
Verify the glow plugs are getting power.

Man, you nailed it! I owe you one. I guess when I went to land my fat butt in the seat, I hit the Aux and jammed it on! Thanks alot. You would think they would put this in the service manual. If you ever get to San Dego, I'll buy you lunch!