My new 4300 project

[beenthere]

Thanks for the update.
Any pics and some description of the injector tester?

Look forward to your progress updates.

 

[beenthere]

Brilliant... and very clever. Thanks for sharing.. :thumbsup: :thumbsup:

 

[larboc]

It's alive!

Fired it up last night, virtually nothing out the crankcase breather compared to before. (no surprise) the cracked piston was the problem. Purs like a kitten, really smooth.

The only issue I have is that I think I have one of the injectors set at a little too high a pressure because I get a miss and tons of blue smoke above 2100rpm. The smoke gets worse the faster I rev up to PTO speed. Of course it's cyl. 3 injector and the tank is back on so it's going to be a pain to get it out but at least it won't be stuck.

The factory spec says 2845psi to 2986psi

I went up one shim size (0.04mm) on 1 & 2 and went up two shim sizes on 3 because it was only at 2800 when I went up 1 size.

Currently the pop off pressures are at 1) 2825 2)2875 3) 2950

My theory is that the pump has some hours on it now and is having a harder time making pressure. I'm going to try cracking the line to cyl 3 at the pump to see if the miss goes away, then I'll dig the injector out and go down a shim size.

 

[larboc]

I don't know what's going on now. Before pulling the injector I cracked lines with it running and when I cracked cyl 2 so it wasn't firing, all the smoke went away. It didn't appear 3 was the problem. So I pulled injector 2. I took it apart, cleaned it, verified the nozzle holes were clean using a flashlight, popped it, and put it back in. It behaved exactly the same way. So I swapped #2 and #1 injector. Now it blows blue smoke at high speed no matter what injector line I crack. I'm at a bit of a loss. I think I might pull all the injectors out and put the original shims back in. My only thought is that the pump can't handle "new" pop off pressures anymore.

Also, the nozzle sleeves are burned/melted on one side on both #1 and #2 injectors, I didn't pull #3 yet. No clue how they could have been damaged so quickly. No signs of leakage around the copper washer. No leaks around the injectors while running.

 

[texasranger556]

That's discouraging. Did you have the pump out at any point and possibly get it out of time? Compression now looks good in each cylinder?

Just tossing some ideas, it sounds like you have more experience than me.

 

[larboc]

That's discouraging. Did you have the pump out at any point and possibly get it out of time? Compression now looks good in each cylinder?

Just tossing some ideas, it sounds like you have more experience than me.

I never took the pump off the plate so I wouldn't have to worry about timing. I just lined up the dots on the timing set when reassembling, and I made dang sure all the dots were lined up before putting the timing cover back on. It would have to be a whole tooth off if it were off and it runs and starts great up to 2000rpm. Compression is great now, virtually zero blow by. I agree it seems like the fuel is getting into the cylinder late, but I'm thinking this is due to an injection system issue since the problem changed with the injector swap.

 

[larboc]

Does anyone know if the "A" marks on the idler and crank gears are supposed to align as viewed from the front, or align their corresponding groove and tooth? Since the crank gear is really long these two ways would be about a tooth different. Manual is vague.

 

[beenthere]

larboc
Can you get a pic of both ? Would be helpful.

 

[larboc]

I already buttoned it back up with it set the way I'm pretty sure it came apart. It's also exactly the way that dfkrug's looks in the picture he took.
http://www.tractorbynet.com/forums/...eere-4300-complete-rebuild-7.html#post1712200

For some reason though my injection timing was retarded. I had to advance about 8 crank degrees to get to the 14 degree mark. That is about equivalent to a tooth. Once I did that the smoke went away and it ran great but made me nervous that the cam might be off too, why else would have injection suddenly been retarded after a rebuild?

Tore the front cover off, huge pain with the engine in tractor to see if I somehow mistimed it. After fighting the compression of a fresh motor to turn it over about 30 times to get the marks to line up, they were the same as dfkrugs, and the way I remember taking it apart-the A tooth matches the A groove so the A's are staggerd when viewed from the front.

I put it all back together without changing any gear timing and put an hour of load on it tonight to start breaking it in and it seems like it's running really well.

All I can guess is that 1600 hrs on a pump combined with freshened up injectors combined to ****** injection by a few degrees.

I also put in new deere injector nozzle heat shields. I didn't push the first ones all the way onto the injectors the first time and they burned up one side.

 

[texasranger556]

Glad you got it fixed. It makes sense that shimming the injectors would ****** injection timing, but I'm surprised it was that big of a change!

 

[larboc]

Glad you got it fixed. It makes sense that shimming the injectors would ****** injection timing, but I'm surprised it was that big of a change!

My thoughts exactly, which is why I blew 10 hours tearing back in to check my work. I wish I had taken more pictures during assembly. It would have removed any doubt.

 

[dfkrug]

All I can guess is that 1600 hrs on a pump combined with freshened up injectors combined to ******
injection by a few degrees.

I would not have expected that.

You say the smoke was blue, and not black (or white)? If blue, I would suspect engine
oil burning, and not excessive diesel.

 

[larboc]

I would not have expected that.

You say the smoke was blue, and not black (or white)? If blue, I would suspect engine
oil burning, and not excessive diesel.

Definitely diesel blue smoke. It happened with the misfires and I know the difference in smell. I'm still scratching my head, but it was blue diesel smoke.

 

[larboc]

Glad you got it fixed. It makes sense that shimming the injectors would ****** injection timing, but I'm surprised it was that big of a change!

On second thought, the injectors shouldn't have affected the spillover timing since they aren't connected while in use. Now I'm even more confused. O well I guess, it's running great so I'll just keep working on breaking it in. Seems to have more power than it used to.

 

[steviep]

Glad to see your back up and running. I hope to hear about my engine this week.

 

[steviep]

Well they got the engine apart and the rings were blown out on the #1 piston. Ordered piston kit from mytractor ,ordered oversize with standard rod and main bearings the sales lady was very helpful. Larboc do you have a link to the on line JD company you used

 

[dfkrug]

Well they got the engine apart and the rings were blown out on the #1 piston.
Ordered piston kit from mytractor ,ordered oversize with standard rod and main bearings

I guess the bore was damaged, too? Why replace rod and main bearings? What about the other
cylinders?

 

[steviep]

Actually the bore was in good shape it was just a little out of round. I could have had it just honed but the machinist recommended it to be bored and he's the expert with a great reputation. As far as replacing the bearings they come with the kit so out with the old and in with the new, they are 16 years old.

 

[dfkrug]

If I bored one cylinder and installed the .25mm oversize piston, I would do all three. This is
more important than changing out the main bearings, esp if they are in spec. I did
that on two 955s and one 4300. I would be concerned about out-of-balance condition
with mis-matched cyls.