Case 580K Idle Under Load Problem, Misses/Chuffing

[crs996]

Hello,

New to me 1990 Case 580K Phase 3 loader/landscaper owner here, needing some help with an idle problem. When under a light load such as turning the steering wheel while in gear, or raising the 3pt and loader together the engine chuffs/misses a bit, puffing a a small amount of black smoke after a chuff on occasion. This only happens with a light load, idle with no load is very smooth. Idle is set to approx. 900 rpm.

Apart from this, the tractor runs really well, and is totally smooth under load as soon as I add a slight bit of throttle. There is no smoke at startup or under load unless it is really lugging. The hour meter shows 9950 hours, but there is a reman. tag on the injection pump, minimal blow-by and no oil consumption so the motor may have had some work done as well. I've put about 20 hours on it.

What I've done: When I bought the tractor about a month ago, as soon as it was delivered I changed every fluid and filter in it, including both screw on fuel filters and the in-line fuel filter and both air filters.

Any ideas? I'm hoping it is not the injection pump, perhaps injectors? Thanks for any help!

 

[alrman]

It does sound a little like injectors. If injectors were serviced when the pump was done, they should have no paint on them, look a little rusty? So if they still have paint on them, they may need looking at. If the engine has bad mountings it could do similar thing by having excessive movement. Maybe worth a look.

 

[thepumpguysc]

Have you checked the pump to engine timing?

 

[crs996]

Thanks for the replies. Alrman, was hoping to hear from you! From what I can see there is paint on the injectors. Forgot to mention that I did replace the front engine mounts, with help from a post you made a few years ago. It made a big difference in smoothness overall but not with the idle issue.
Pumpguysc, checking pump timing is way above my pay grade mechanically, is it simple to do?

 

[thepumpguysc]

There IS a "proper" procedure..but the easiest thing to do is...See the timing mark on the mounting flange on the pump?? Now see the timing mark on the engine block?? are they lined-up??
Loosen the 3 nuts on the pump flange and turn the pump SLIGHTLY [about a dimes width] in one direction or the other..TIGHTEN THE NUTS BEFORE RESTARTING the engine..If it helped, leave it alone..IF NOT, go the other way..IF it didnt help in either direction get the injectors checked..

 

[crs996]

Thanks thepumpguysc, so if they are lined up should I still try adjusting? Also, what style injector puller will I need to get the injectors out?

 

[thepumpguysc]

yes, try adjusting the pump timing before removing the injectors..
as far as type of inj. puller..a slide hammer type will do..you can rent them from the auto parts store..