New injectors and pump. Exhaust smoking.

Brian VT

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I put in new injectors (a month ago) then saved up and got a rebuilt pump. Both from a recommended rebuilder.

She starts instantly and idles great. The high idle solenoid seems to be working and the idle drops after a couple minutes.
There's a quick puff of black smoke at startup and then some almost invisible smoke from then on that doesn't go away even when up to full temp.
That same slight smoke is still there while cruising and normal acceleration. And she goes like hell now! (compared to before).
If I get on the throttle a bit more it rolls coal very easily. Seems like too easily.
And one other thing, that may not be relevant, I've had it stall when coming to a stop unless I come in easy and keep a bit of pedal on to let her wind down gradually. Then it sits at idle nicely. At idle, in park, if I do a quick stab at the throttle it will quit almost instantly after I let off.
My pump mark is turned about an 1/8" toward the passenger fender. I read here somewhere that if it rolls coal easily then the pump is turned too far in that direction. But 1/8" doesn't sound like very much compared to what I've read here?
I turned up the idle adjustment but that just made it rev higher and I still got the letoff stall so I turned it back down.
That's all I've done.
Then I drove it today and the stall at letoff is gone. It returns to idle nicely with no stall. Even if I do a quick stab while sitting in park.
But today the engine sounds "clacky". Where did that come from?
What the heck is going on?

I was going to take it to camp tomorrow which would put me on the freeway for the 1st time since I got this truck.
Now I'm afraid I'm gonna cook it if I go 65mph for 1/2 an hour. :-(
 
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FrozenMerc

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If it is black smoke, your fueling may be too much. You could try turning the fuel adjustment back some, see if that clears the smoke up.

The new "clacky" sound may be a slip in the timing. Make sure the pump bolts are tight and nothing has moved.
 

Brian VT

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Thanks. Good idea on the pump maybe moving. That's easy enough to check.

The fuel adjuster looks like a pita to do but I guess may have to give it a go.
I can't get to that before tomorrow. Am I correct that overfueling can cook the engine so I shouldn't drive it? I won't be pulling or hauling anything (maybe a mattress).
 

Brian VT

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The pump hasn't moved. So why did it start being clacky all of a sudden?

I guess I'll try to turn the fuel down to deal with the smoke. :-(
 

gandalf

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How did you time the new IP? A steady grey smoke such as you've described is frequently an indication that the timing is a bit retarded.
 

Brian VT

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No name calling! ;-)

I haven't delved into exact timing yet. And I don't have time to right now.
I guess I'll try moving it a bit to starboard.
Looks easier than adjusting the fuel. But I'm still concerned about that. The rebuilder said it's set for between 6.9 and 7.3 non-turbo. Will over-fueling kill my engine? Has it already hurt it and that's why it got clacky?
 

Brian VT

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The pump won't move any further to starboard.
And I don't have time to start loosening fuel line connections.
I guess I'm not going to camp. I'm afraid of cracking a head if this pump is set too high.
 

IDIoit

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who built the pump?
there is only 2 sources i would ever buy a pump from now a days.
what did the meter say when you timed it?
 

IDIBRONCO

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As long as you're not seeing black smoke constantly while you're driving, having the fuel setting too high on your pump won't do any damage.
Now your engine sounds clacky, but the timing hasn't changed. I'm starting to think that maybe you're sucking air into the fuel system somehow. That would explain the noise. It certainly explain that tendency to die when you let off the throttle.
You need to forget the puff of black smoke at startup. It's perfectly normal. I've seen some 7.3 PSDs that did the same thing. I believe that it's caused by fuel that is being injected while the starter is spinning the engine over. That fuel doesn't get burned until the engine is running. There's a little bit of extra fuel in some cylinders so that gives you the puff of black smoke on startup.
 

Brian VT

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who built the pump?
there is only 2 sources i would ever buy a pump from now a days.
what did the meter say when you timed it?
One of the recommended 4 here. He said the fuel was set for in between a 6.9 and 7.3 non-turbo.
I haven't had time to set up and learn to use my timing meter yet. But it starts instantly and pulls like hell so I don't think it's that far off that I would be getting these symptoms?

As long as you're not seeing black smoke constantly while you're driving, having the fuel setting too high on your pump won't do any damage.
Now your engine sounds clacky, but the timing hasn't changed. I'm starting to think that maybe you're sucking air into the fuel system somehow. That would explain the noise. It certainly explain that tendency to die when you let off the throttle.
You need to forget the puff of black smoke at startup. It's perfectly normal. I've seen some 7.3 PSDs that did the same thing. I believe that it's caused by fuel that is being injected while the starter is spinning the engine over. That fuel doesn't get burned until the engine is running. There's a little bit of extra fuel in some cylinders so that gives you the puff of black smoke on startup.
The black puff at startup seemed fine to me. But thank you for the confirmation.

I like the idea of maybe sucking air as I didn't know that I should replace the olives in the supply line to the pump. I didn't even know what they were at the time but I noticed that they didn't look great when I was putting it back together. They're not leaking fuel but could be sucking air?
But would I still be able to roll coal so easily? Wouldn't sucking air make it lean and clean?

And thanks for the assurance that I won't burn it down if I stay away from rolling coal.

Now your engine sounds clacky, but the timing hasn't changed. I'm starting to think that maybe you're sucking air into the fuel system somehow. That would explain the noise. It certainly explain that tendency to die when you let off the throttle.
The stalling thing was gone today. The same day that it started being clacky. And I hadn't done anything to it since I last drove it.
 
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Black dawg

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One other thing to add. I would not adjust the fuel screw on a fresh rebuild without express consent from the builder. I would not want to see you void a warranty chasing a problem......

I wouldnt adjust anything......get timing set with a meter so that is known.

When you say roll coal, how much are we talking? These dont generally put out a puff of black smoke at start up unless the fuel is up a couple flats........
 

IDIoit

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retarded timing will cause white smoke.
you need to adjust FUEL timing.
it will run -10 ATDC and 16 BTDC. ask me how i know. lol
get that meter on it.
 
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