* Cold Weather Starting Difficulty *

[EvergreenSD]

It worked! It worked! It worked, but I think I went a little bit too far. My cold-start this afternoon went dramatically better that it has previously. There was but one tiny puff of smoke. I can't say it ran 100% smoothly but it was an enormous improvement and it took the little nudge of throttle to help it warm up without the missing and embarassing smoke screen. I am very pleased, to say the least. I took it for a drive to make sure there were no driveability issues and all was well, I think it sounded better, quieter and smoother revving.
There was one little thing I noticed when I got to the store, however. It wasn't too eager to shut down. It just kept running when I turned off the key. It got much quieter but shook a bit and just kept right on going, much like a gasser 'dieseling'. Next I'm going to try splitting the difference between where it was and where it is now, though any thoughts are more than welcome. I rotated the pump counter-clockwise so that the alignment mark on the pump is maybe 1mm to the left of where it was. The next setting I try will be within the margin of the v-shaped groove in the timing housing just to give and idea of how slight a movement is involved. Thank you Zen, I'm sure you would have slapped me if I were in reach and I might have reached this point sooner. I am feeling much relieved already as well as being hopeful that I will be able to get my fuel mileage closer to what I have been hearing from others. I would be lost without this board.

PS. Before I 'Turbo it' I will have to wait until this engine is in a 4x4 chassis with taller gears. Patience my son.

[philip]

SNIP: There was one little thing I noticed when I got to the store, however. It wasn't too eager to shut down. It just kept running when I turned off the key. It got much quieter but shook a bit and just kept right on going, much like a gasser 'dieseling'. SNIP

On both ends of the linkage rod connecting the IPC to the Fuel Control Lever is a plastic bushing (2). If I recall right, I replaced them with very similar bushings from True Value Hardware. Had to file them down lenthwise a teeny bit. Think they were 1/8" ID.

[EvergreenSD]

Thanks for the tip. I'll admit that I was a little confused by how it kept running, regardless of pump timing. Once the fuel is shut off it should die, right? Maybe it isn't quite reaching the 'off' position. With the timing a little off it would die when most of the fuel was cut off and now it will run with just a trickle? I let it run for maybe 20 seconds and there was no sign of it dying, I don't know how long it would have kept up. It sounded kind of funny actually, my street-ripping, tire-burning, civilian-terrorizing 61 bhp( ) had apparently transformed itself into a lawn-mowing 1/2 hp perpetual motion machine. I will definitely look for play in that area. Have you guys come up with a NissanDieel logo I can have tattooed on my forehead yet?

[philip]

Thanks for the tip. I'll admit that I was a little confused by how it kept running, regardless of pump timing. Once the fuel is shut off it should die, right? Maybe it isn't quite reaching the 'off' position.

With a lot of slop present at both ends of that linkage rod, the IPC can't pull the Fuel Control Lever quite far enough to immediately achieve fuel OFF position.

With the timing a little off it would die when most of the fuel was cut off and now it will run with just a trickle?

No. Your pump timing has no bearing on Fuel Control Lever position. Timing

I let it run for maybe 20 seconds and there was no sign of it dying, I don't know how long it would have kept up. It sounded kind of funny actually, my street-ripping, tire-burning, civilian-terrorizing 61 bhp( ) had apparently transformed itself into a lawn-mowing 1/2 hp perpetual motion machine. I will definitely look for play in that area. Have you guys come up with a NissanDiesel logo I can have tattooed on my forehead yet?

Those moments were just fuel reduction. On the smoke setscrew thread, you will notice the Fuel Control Lever effect is stepped only insofar as the IPC/DPC control is concerned.

[redmondjp]

Evergreen--glad that this worked for you! I just had all of my glow plugs out last night, powering each of them up, verifying proper operation, cleaning all electrial connections, and whoa, it was after midnight so I had to quit for the evening.

It started pretty well this morning on one glow cycle with only a bit of missing, but it was fairly dry (no dew) and 55 degrees. I'm trying to get it to start as well when it's 35-40 degrees (bonus points if on one glow cycle ), which as you know is pretty typical in the winter around here.

I'm thinking of doing exactly what you did--slightly advance the timing. I know my '81 Rabbit responded very well to just a bit more advance.

It's a heck of a lot easier to just slightly advance and try it, than it is to disconnect all of the lines and do the drip-tube measurements. I'll be out in the driveway tonight!

[EvergreenSD]

I started up this morning when it was about 40 degrees. It had been down to freezing overnight, though, so I'm sure the engine was still very cold. It wasn't the smoothest start but the smoke was dramatically reduced and it warmed up to a smooth idle much more quickly. This was on one glow cycle, I suppose it would have been worth cycling them twice.
I also inspected the IPC linkage rod and found that it does need bushings. There is alot of slop there and I found that the engine would shut right off it I moved the lever just a hair more so I think that will solve the run-on. It's very interesting to me that this situation appeared when I changed pump timing. It is obviously running more efficiently now so that it can keep running on that tiny trickle of fuel. I am tempted trying to advance it just a hair more to see if there's more improvement to be had.

[philip]

SNIP I also inspected the IPC linkage rod and found that it does need bushings. There is alot of slop there and I found that the engine would shut right off it I moved the lever just a hair more so I think that will solve the run-on. It's very interesting to me that this situation appeared when I changed pump timing. SNIP

The Fuel Control Lever position is not influenced by IP body rotation but ... Fuel Control Lever position is influenced by IP body rotation relative to the IPC controller motor/mechanism when you move from RUN toward OFF. As you discovered, when you're on the edge, it takes only a fraction of an inch to stop short of true fuel shut OFF position.

[asavage]

Fuel Control Lever position is influenced by IP body rotation relative to the IPC controller motor/mechanism when you move from RUN toward OFF.

So, generalizing, if one changes the IP timing, one should re-check the IPC rod adjustment?

[philip]

So, generalizing, if one changes the IP timing, one should re-check the IPC rod adjustment?

Certainly when a "new" shut-down problem follows a significant alteration in IP position.

OFF is OFF only when the Fuel Control Lever is rotated sufficiently CCW. Zoltan found out just how little movement is actually required compared to the travel available.

[philip]

It's a heck of a lot easier to just slightly advance and try it, than it is to disconnect all of the lines and do the drip-tube measurements. I'll be out in the driveway tonight!

Is it a genetic or spiritual failing in human beings that makes us 1st choose the path of least resistance?

It is not difficult to remove all injection lines NOR is it difficult performing the drip method timing check. But of course, we waste HOURS tinkering with our hobbies without a second thought.

[Knucklehead]

I'm glad you got it fixed, and sorry I missed it, but just for everybodys reference, I was going to suggest one other possibility.

If there is any restriction in the fuel line such as a plugged fuel filter, any entrained air in the fuel will be pulled out of solution (think of it as precipitation) and after shutdown will coalesce in the filter, the lines, and the pump. Upon startup the typical foul running will occur until all the air is run out. Because the air in the lines after the pump compresses upon injection, the delivery is both retarded and diminished. If driving has been vigorous and/or in hot weather, the sloshing fuel in the tank will tend to pick up more air.

And just for the record, the diesel tech who said a visual inspection of injectors is adequate is full of it. If you plan on owning an SD for any while, either get to know a good shop or set up your own test stand. Checking pressure and spray pattern is routine maintenance, and the only way.

[zen]

And just for the record, the diesel tech who said a visual inspection of injectors is adequate is full of it. If you plan on owning an SD for any while, either get to know a good shop or set up your own test stand. Checking pressure and spray pattern is routine maintenance, and the only way.

too right!!