New injectors and pump. Exhaust smoking.

Brian VT

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Ok. I finally got my DTI timing unit out and working and adjusted the timing to @ 9.5
It was @ 12 before.
I'm still getting smoke but it's different now. And the engine still sounds "clacky" to me. But maybe not as bad? I don't really know what "normal" sound is but it seemed less clacky with new injectors and the old pump. And for a few hours with the new pump.
There's a bit of gray smoke at idle now. Not bad at all though.
I've got a steep, low speed, uphill road leaving my house. I left a heavy gray cloud of smoke on the way up. I was on the throttle pretty hard. I couldn't get it to turn black like when the timing was at 12. Once on the flat road I wound it out pretty good. It seemed to clear up a bit after that but the sun was also going down so maybe I just couldn't see it as well?
I guess I'll drive it some more in better daylight for a better idea.

But if this smoke under moderate-heavy throttle continues then is my next step to turn the fuel down in the pump?
 
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ROCK HARVEY

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I would ask the pump rebuilder how many degrees BTDC you should set the timing. I have seen another thread where the builder recommended something different than the typical 8.5 degrees.
 

Brian VT

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Wait. What?
Everything I've read here said set my meter at 20 degrees offset and then set my timing to 8.5-9.5
 

Brian VT

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Dang.
I thought once I got my timing set you guys would have lots of advice for the next move.
 

Brian VT

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You must have my sig. turned off. It's na.

I just turned the fuel down @ 2 flats. Smoke is gone. I can't even get it to smoke on the steep uphill with the pedal to the floor. I guess that's a good thing? And it doesn't seem to have given up any power.
Success? Good to go?
Except that it still seems "clacky" to me. I guess I'll have to find someone else that owns one to compare.
I just remember noticing that it got less clacky after I replaced the injectors (but still on the old injection pump). And it stayed like that for a few hours after I replaced the pump a month or two later. And then it suddenly got more clacky while driving one day.
Now I'm wondering if the over-fueling got it too hot and did damage? I don't have an EGT gauge to know if it got hot. I drove it @ 60mph for maybe 10 minutes and was never loaded or pulling anything. I've pretty much just been test driving this thing since I got it last October. lol
 
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IDIBRONCO

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I just turned the fuel down @ 2 flats. Smoke is gone. I can't even get it to smoke on the steep uphill with the pedal to the floor. I guess that's a good thing? And it doesn't seem to have given up any power.
Success? Good to go?
You should be able to see some black smoke under a load: heavy acceleration, steep uphills, with heavy throttle, pulling a load, etc. You can leave it like it is or you could turn the fuel back up slightly if you wanted to get it "ideal". By slightly, I mean about 1/2 flat.
Now I'm wondering if the over-fueling got it too hot and did damage? I don't have an EGT gauge to know if it got hot. I drove it @ 60mph for maybe 10 minutes and was never loaded or pulling anything.
From your description, no. Driving empty, doing 60 for 10 minutes you couldn't have done any damage unless you had black smoke rolling out of your exhaust.
 

Brian VT

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I could get it to roll black very easily before turning the fuel down. And I did it a bunch of times while test driving and trying to "clean it out" because I've heard that these engines like to be worked.
 

IDIBRONCO

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Driving empty, doing 60 for 10 minutes you couldn't have done any damage unless you had black smoke rolling out of your exhaust.
Let me finish what I should have said earlier. Unless you had black smoke rolling out of your exhaust the entire time.
 

ROCK HARVEY

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Kind of a side note, but I would go ahead and add an EGT gauge since that’s a piece of the puzzle you’re missing. You can get cheap ones for <$30 shipped on Amazon. I have this one in my truck now: EGT Exhaust Gas K Type Probe Temperature Sensors with Blue LED Gauge Combo Kit (℃ / ℉) https://a.co/d/gVFnMqG
 

Brian VT

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I will get to that one of these days. Thanks for the link.
It's running pretty well now. Still a bit of smoke that I hadn't noticed before but not bad at all.
I would be comfortable driving it daily now.
I just want to find out if the "clacky" is normal or not.
The only thing I can think that I could try at this point is replace the olive at the back of the injector pump. What would be the result if that was bad?
Would that cause "clacky" and a bit of smoke?
 

typ4

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Glad you turned it down. Clacky is normal on some engines. Old pump likely worn enough to be very retarded.
Check timing again after a few miles. Lots of new parts go in the pumps when properly rebuilt. They are all a few percent over stock. Some like it some engines dont.
Every setup is different.
No harming warranty issue turning it down. Thats a dial in adjustment. Needs done on all the 6.9 as it turns out.
 

Brian VT

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Thanks Russ.
"Old pump likely worn enough to be very retarded."
Do you mean my fuel pump? Or my newly rebuilt injection pump?
 

IDIBRONCO

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That's talking about your old injector pump. I think that he missed the newly rebuilt injector pump part.
 

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