My 4200 smokes - some white smoke - and I'm not sure if I should be concerned. It has almost 900 hours - I've owned it since it had 780 hours. The smoke is usually hard to detect visually - its really light unless under heavy load. I spoke to the dealer/mechanic last year. His response was:
"Is it using oil?"
"No.And the oil is really clean"
"It can't be the rings so don't waste time on a compression test. Is is losing coolant?"
"It can't be a gasket or cracked head. Where are you getting your fuel?"
"At the local station."
"Are you using normal, over the road fuel?"
"Stop that. Drain the fuel tank and refill it will "off road diesel. Add JD fuel treatment. Run it for a while, the problem should go away."
Well, its been almost a year and about 50 hours later. This week I had it running with the lights on after dark - its smoking a lot more than I would have expected. I've only lacked power one time - moving very wet heavy snow with the 59 SB - not surprising. So, I'm pretty sure I don't have a compression problem or a blown head gasket/cracked head. Yesterday I checked the valve gap - 3 were within specification, 1 was slightly too tight and 2 were slightly lose - all have been adjusted and verified.
The service manual says it could be an injector problem.
The owner's manual for the 4200 says "Inspect fuel injectors" every 500 hours. I have the service manual & the instructions for removal appear to be straight forward. It also suggest it could be a temperature issue but the engine is not over heating so I suspect that's not an issue.
Question: Has anybody removed and inspected the injectors?
Question: Does anybody know what I'm supposed to be looking for? The service manual describes connecting them to a "testing" device and describes the procedure - I imagine I'll have to send them out to a diesel repair shop to test them and there's a few near me.
Question: Should I get some fuel injector cleaner and run it through the engine? If so, what brands have people tried and with what level of success?
Question: Has anybody tried to rebuild their injectors? If so, how hard was it?
Question: Am I just being too careful?
I've priced out new injectors - $225 each so I'm not prepared to just replace them to "see what happens."
All opinions welcome.
Thanks in advance.