Old enough to smoke

[bandmiller2]

I have a Lister ST-1 that seems to have decent compression and starts easily. Is it usual to see some light blue smoke when warm running. In other words do any of the older Listers burn clean and smokeless. Frank C.

[38ac]

When everything is up to snuff the exhaust should be clear almost up to the rated load and then just a barely preceptable haze. My SL1 and LD1 one both have clear exhausts except when starting or lugged down. If your not burning oil I suspect a dirty or stuck injector. Do you get an audible creak from the injector when cranking?

[dieselgman]

I concur... light blue smoke often means you are burning some lube oil - rings and/or valve guides are worn. Exhaust should be clear.

dieselgman

[millman56]

 Frank,       Listers do say in the fault finding sections in some operating manuals, that smoke as you describe,  can be a symptom of running the engine  lightly  loaded, the long term effect of this is stuck rings and bore glazing.     As 38ac and dieselgman say, one in good order should run a clear exhaust, that said I find it doesn`t take a great reduction in compression to make them smoke.  

Mark.    

[bandmiller2]

Thanks guys,this engine came off a barge in boston harbor used to run a 12v gen for safety lighting and I have a hunch it has always run lightly loaded.The guy I bought it from said it was run very little. It is now coupled to a 10 kw generator, when I test run I use a 1500 watt electric heater for a load which is nowhere near enough load as you can't detect any change in engine pitch when plugged in.  38AC I really haven't noticed the injector creaking will have to listen next time. Any majic snake oil that would help (as if I don't know the answer). Frank C.

[38ac]

I dont know any bottled magic cures that work well enough to mention them, sorry. Remove the valve cover and take a listen to the injector. Another field expedient injector check is to crank it over about 1/3 the speed you normally would to start it. With the decompressor left on and rack set to over fuel for starting you should be able to feel a very distinct increase in turning effort to pop the injector every other revolution.

Another thing I neglected to mention is the correct grade of engine oil. Our SL started hard, smoked and wet stacked badly with 15W-40 in the crankcase. When the proper 10W grade was installed all that went away in about 10 minutes of running.

[dieselgman]

No magic snake-oil cures, but I might mention that 100% Biodiesel run through a system can sometimes clean it out nicely - and will restore power/performance if that system has not been damaged beyond a bit of residue causing parts to stick.
Cheap and easy!

dieselgman

[BruceM]

+1 Vegetable oil works very well as an injector cleaner with parts soaked in it overnight,  so running biodiesel to see if the cylinder glaze will dissolve some, rings will loosen up and the injector will clean up is a very good idea.

I'd even go so far as to flood the piston with a cup of straight vegetable oil or biodiesel, crank it around a couple times with the injector still out, and keep it refilled for a couple weeks, suck any residual out then change the crankcase oil and see if it helped.  Just don't hydraulic lock it, that oil must be gone before you fire it up.

[buickanddeere]

Load her down to max KW out and run 200F coolant temp for a couple of days.

[bandmiller2]

I'll try putting her on a vegie diet and a good load. Frank C.

[BruceM]

It was Bon Ami in the air intake (fine feldspar abrasive). I know some guys swear by it.  But that's not going to work if the rings are sticking due to carbon build up.  Either running or soaking, I'd give the biodiesel a chance first.

[bandmiller2]

Bon ami has been in the back of my mind, it was once recommended by Cat. to seat rings and break cyl. glaze. Have any of you guys done it.?? In the mean time before I find some bio diesel I put some seafoam in through the intake primer to help free the rings. Hope springs eternal. Frank C.

[buickanddeere]

  I can't imagine pouring abrasives into the engine over some light blue smoke. It's not a prime power unit and engine oil is cheap. Odds are it's never been loaded to max and heated up. The rings and lands are probably stuck with soot or carbon. 

[Schwen]

Is it possible for a ST1 to pull the head, slip the barrel off the piston, clean the piston rings etc and then slide the barrel back over the piston while leaving the conrod/pistopn assembly on the crank?

[dieselgman]

Yes, the ST is normally serviced in this way. It is quite easy to replace the conrod bearing at the same time as well, with easy access to the crankshaft via side door.

dieselgman