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Re: 3406b smoke

I wonder if the the " clatter" is diesel knock. The 3406B  engines had problems with the timing advance unit (TAU) where the carrier would loosen and slip in the drive housing. This resulted in the flyweights of the TAU rotating slower than they should be for a given engine rpm and resultant retarded timing. This would not create diesel knock ( advanced timing will do that) but could certainly create smoke.

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Re: 3406b smoke

[ Edited ]

Thanks for the reply, cook.  (chr - is that ch robinson by any chance)  I originally thought I had a valve tap.  It came on slowly and never got too bad.  Therefore I rolled with it while paying attention to any change in volume.  Then one day the tapping stopped altogether.  I thought to myself, the valve train is simple.  If there is too much clearance then there is too much.  These things do not correct themselves.  After a while the tapping returned but louder, resembling more of a small clatter.  Accompanying this development was an intermittent miss.

I was then that I noticed the long plume of smoke following when I put the pedal to the metal.  However, there is a further development, since my original post.  The plume of smoke is also intermittent.  I can get on it and look in my mirror at the smoke.  Then, a few miles down the road I'll get on it and little smoke.  The clatter is largely gone, but the intermittent smoke problem remains.

 

I relate the noise and the smoke.  If the injector pump is a silent problem, then I have to think that my problem is not in the injector pump, because that noise appears to me to be related to the beginning of the problem.

I have come to my own conclusion that the problem must be an injector.  I posted because I was wondering if somebody who read my post had a similar experience.  If I hear "Yeah, that's a bad injector, I had the same problem", then I will shut it down, pull the injector, and replace it.

I'm on the road now, away from my workshop, and I am afraid of turning this problem over to an unknown shop.  I think you can appreciate my concern in that department.

Thanks again, cook!

Contributor

Re: 3406b smoke

Suggest you check / adjust valves then compare the amount of thread protrusion of each adjusting screw above the locknut. A big difference in protrusion may indicate a valve camshaft lobe and or cam follower failure as you have reported a tapping noise from the engine. While the valve covers are removed also check for a broken rocker shaft or bracket. The recent development of smoke could indicate a cam lobe failure in the fuel pump but generally you dont hear any noise with this type of failure.

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3406b smoke

About a year ago I deleloped what sounded like a valve tap.  I used a stethoscope and traced it to #3.  After about 6 months the tap went away on its own.  After a few months it returned, as more of a clatter.  The tap rate is half the rpm so it's upper end, not lower, for sure.

The clatter is intermittent.  It clatters, then it doesn't, then it does.  Sometimes I notice a miss, then the miss disappears.  The clatter has largely subsided, but now I notice when I press the pedal to the floor, (I'm presently bobtailing) I get a continuous stream of dark grey smoke from the stack.  This is new.  The engine always smoked, some, but never put out a long continuous trail on hard pull like it's doing now.

Malfunctioning injector?