excessive smoke, moderate oil consumption
 

neophyte w/ a 83 300cd...160k...all records current....no leaks, but rough cold start-up & excessive smoke under heavy acceleration (especially when turbo kicks in)...changed fuel & air filters...what next,?...could valve adjustment fix smoke?...car also enjoys 26-29 mpg & cruises fine @ 70-85mph
thanks in advance
pfm

paddy:

You mention that all records are current on this car, but it's not a bad idea to assume NOTHING has been done to her in order of recent maintenance. In so doing, you might want to adjust valves, replace both fuel filters (which you did), and consider replacing glow plugs, especially in light of what you mention about cold starting. A valve adjustment may lessen your smoke on hard acceleration.

Do you get blue smoke on startup? This usually means bad valve guide seals, not too surprising at 160,000 miles.

What do you mean by excessive smoke? Does the car behind disappear in a black cloud, or do you just see a flicker above the deck lid? Latter is normal, you should see some smoke at full throttle/full boost.

If you are seeing bluish gray smoke, not black, then you are looking at either excessive blowby (easy to check) or leaking seals in the turbo. The latter will soon result in LOTS of blue smoke, and serious oil consumption.

Peter

I assume you mean excessive black smoke on hard acceleration (not blue). Keep in mind these diesel will always smoke a little black under heavy load.

This is how I would attack this. First, check each of the glow plug resistance with an ohmeter. They should be a couple of ohms or less (a short). If you find any that are open circuit, replace it.

If the glow plugs are ok, or if you replace a bad one or two and you still have the miss on start up, definitely adjust the valves. You probably need to do this anyway. That should solve the miss at idle.

The valve adjustment might help to reduce the amount of smoke on hard acceleration, but it also might be the injection timing. You can do a search on drip method of injection timing if you need it.

This also assumes you have fresh diesel fuel in the tank.

Good luck

Joe