Blue Smoke

[marty]

Have a 20 Year Old Ford 4600 SU and last year it began choking out and then discharging blue exhaust under higher RPM and under load. The dealer replaced the fuel pump and it seamed to help a little.

The condition seems to be getting a little worse, so when I was replacing the fuel filter I noticed the injectors had never been changed. I replaced the injectors and the it still smokes badly.

Could this be bad valves or seats? Could a person replace the valves and seats from the top - under the valve cover? Other sugestion??

Thanks in advance!!

 

[ans38]

Marty,
It could be a stuck or burned valve. It also might be some bad rings. Is the tractor burning engine oil? What do you mean by your diesel "choking out"? I would look at your air intake filter first and make certain it isn't plugged or coated with oil. (It almost sounds to me like an aspiration problem if it only occurs under a heavy load.) If you have to do a valve replacement, you will have to pull the head. You can make valve lash adjustments under the tappet cover but the head will have to come off to replace/inspect the valves and seats.

Try to keep it simple at first and look for the obvious. If you replaced the fuel filter, pump and injectors, look at the air filter next. I'm not very familiar with Ford diesels but I would look at the air filter. Just curious-have you tried venting your fuel lines to the injectors to make certain there's no air trapped inside?

Please keep us posted. There's bound to be someone on the site that knows a little more about your problem.
Good luck!