Case 500

[Scupper]

Still blowing excessive blue/white exhaust. Runs terrible until it starts to warm up (Smokes and spits unburned fuel), then settles out, but still smokes excessively, fairley equal between the 6 cylinders.I've had the heads and injectors redone, new sleeves and rings, compression is fine, powercells clean, injection pump timing is right on.Valves adjusted properly, etc etc. Could a fault in the injector pump cause this? Does this injector pump (PSB-6) have a mechanical advance? How about an adjustment to adjust the amount of fuel delivered? Any ideas appreciated, if I can't fix it in a week or so, off to the shop it goes.

 

[Kelly MT]

My 500 did something like this and was starting to "make oil". The seal on the transfer pump shaft had worn a groove in the shaft. I machined the seal seat back one eighth of an inch and installed a new seal. Problem solved. No one could find a new shaft/gear in North America. Runs great now. PK

 

[Scupper]

I'll take a look at the "make oil" idea. I hadn't thought of that. This really has me baffled, and I've tried everything I can think of or has been suggested. Thanks for your input.

 

[Doc Larry]

1. Does this have the "wick" type oilers in the rocker arms? If they are gone, or if someone has put in pipe cleaners, your oil consumption may be due to over-oiling the valve stems..
2. Has this been run long enough to seat the rings? You can have good compression but still be using too much oil. It can take a while...

Larry

 

[Scupper]

It does have the wicks in the rocker arms, they look to be original, so I didn't fool with them. As for wearing in the rings, I'm a hobbiest, so don't really work my tractors except for parades and pulls. So after the winter overhaul, I've probably put 2 hours unloaded time on the engine. I had not had ring seating problems with the gas engines I'd overhauled, so hadn't really considered that. I might have to rethink that! Someone mentioned I might try advancing the timing just a tad. I may do that, and see if any changes occurr. Thanks for the idea.

 

[catfish 01]

I'm running a 500 for an irrigation motor, if your sure the injectors are ok, I'd have the injection pump checked. I had two pumps fixed, they cost me $250.00 each. Make sure the air cleaner is clean. If fuel leaks into the oil a head seal in the pump or the transfer pump seal can leak.


 

[Scupper]

I think I will take it in to have the injection pump checked. Yesterday I replaced the bleedof line on the pump with clear tubing, and observed bubbles. I din't think they should be there? Anyway, I'm tired of fooling with it, so it's time to pay the professionals. I do have to say you seem to have gotten your pumps repaired pretty reasonably! I'll post again after the problem is fixed.
Later.