I decided to investigate further into that mystery dead glow plug/smoke puff today since I suspected they were related. It turned out to be right on the front (closest to the alternator - I think thats the number 1 cylinder...too lazy to look it up right now
) so it was easy to pull the injector and see what it did on the pop tester. It starts ******* at 1700 but its a lazy, steady stream of liquid instead of mist
.
Hold it steady at 1500 and it leaks. Not very much, but it still leaks
Push it hard enough and it does atomize the fuel, but there were several visible strands coming out instead of the usual crisp snap of fuel atoms that I want to see (yes, my eyes are good enough to see fuel atoms
).
So I rummage through my old set of delphi injectors and the first one seems to shoot ok. Put it in the truck and nope - makes an audible knock, and the truck smokes when reved up. Pull it out and try another one. This one spits clean and short right at 1900 PSI (steady stream pulses between 1700-1800). Put it in and it seems to run well. The knock soon fades and I observe the exhaust smoke in direct sunlight to see if its cleared up at all.
There was still the slightest intermittent grey puff, but when the high idle/cold advance drops, it becomes steady.....hmm.....
The truck behaves on the test drive and pulls well. When I get back, I park it so that the tailpipe shoots across the rays of the sun again and I eyeball it to look for any signs of smoke. I have pretty good eyesight (when I'm not spending most of the day on forums or electronics PDF datasheets
) and I can't detect anything. Just the heat distortion venting off and a smooth idle. There is still a slight audible tick, but it could be there just because I was looking for it.
I'm hoping for another towing run tomorrow, or the day after. I find it hard to believe that I would to better than before, but it will be interesting to see if this changes anything. The horrible spray of the injector makes me think it could have been the reason for killing that glow plug (had a spare and replaced that too). The smoke rolling on slightly after the cold advance kicked off also makes me wonder if I shouldn't be at a slightly more advanced timing as well. Previously I thought my glow plug failures were related to the timing being too advanced, but at least on this hole, it seems to have been from the injector. I won't change anything yet, but am open to any ideas.
Sux not being able to time it properly
)
). Drove up a local mountain, did some 70 MPH cruising but at least half of this was short trips of 10 miles or less in stop an go traffic. The number doesn't surprise me at all. There was some towing of our boat but again, that was a fairly short distance.
