did I break anything?

[rsallen]

What the on the unit injector test DOESN'T tell you is what the opening pressures are.
Unless you have some idea about what you're looking at the test you ran probably tells you nothing.
Why full throttle? What did the atomization of the fuel look like. What was the cone pattern? Was there any leakage after?
As you described the test and results it sounds like you should get the injectors to someone that has a tester to put them on.
I can't say that I've ever tested a diesel injector that would shoot any where near 3 or four feet, as by the time it would get that far away there'd be so little pattern left one wouldn't see any fuel.

Also could you describe exactly how you adjust the valves.
For instance, how do you determine that the top dead center on each cyl. is the compression stroke?

 

[Bob Rooks]

More fuel than necessary travels up the steel lines to the injectors, but they don't necessarily use it all for each piston cycle. The excess that doesn't actually go into the injector gets routed back to the tank.

Not with these Bosch type systems Greg. They aren't unit injectors. The exact quantity of fuel as demanded by the governor is metered by the helix in the fuel injection pumps which is dependent on the rack position. Notice that all of the fuel injection hard lines are exactly the same length. This prevents changes in timing due to the pop pressure swelling for the individual injectors. The "return" lines are just for leak off, and will most likely never see any fuel.
Small amounts of white smoke on a cold start up would be considered normal in most cases due to lower compression pressure due to the components not being at thermal equilibrium and tolerances being greater than normal. Also, cold combustion chambers are another common cause.
The injector pop pressure test is best performed with a special tester found at diesel shops.

Unit injector:

 

[whynot162]

Thank you so much for your help. I am learning that I know nothing about diesels. haha
As far as adjusting the valves, it is a little crude, I can not find the timing marks, So I put a thin wire in where the injector goes, get it down through the pre chamber. When I get the cylinder all of the way up, and both valves are closed, I adjust the valves. There are only 2 cylinders, so I would think this would work. It is not like an old mercedes where you have 5 cylinders, and the valves overlap and I had to be adjusting the intake on one, and the exhaust on another...

the patern was a mist in a cone shape from the injector tip. both looked the same as I cranked the engine

 

[Bob Rooks]

...the patern was a mist in a cone shape from the injector tip. both looked the same as I cranked the engine.

All well and good. Did you notice any dribbling? A chirping sound? But you still don't know what the pop pressure was, and that can affect engine timing.

 

[Brad_Blazer]

Check out this thread and verify you are adjusting the valves properly. It's not the same engine but the procedure of observing operation of the valves should still work. It does sound like you are doing the right thing in your last post. http://www.tractorbynet.com/forums/chinese-tractors/133397-valve-lash-adjustment-2008-jinma.html
Also verify the operation of the compression release shaft and make sure it is not interfering with the valves when not engaged.

 

[greg_g]

Not with these Bosch type systems Greg.

We're basically saying the same thing Bob. "Leak-off" is in fact unused fuel. And one of the basic tests to see if the hand primer is working is to listen for fuel returning to the tank as it transits the return lines. Your definition also assumes a perfectly timed IP, which we have all learned from experience (on Chinese tractor engines) is generally the exception rather than the rule.

//greg//

 

[rsallen]

If I remember the thread right whynot,
Didn't this machine operate just fine before it was torn down for a headgasket leakage of coolant?

I asked about how you did the valve adjustments because if you didn't turn the engine over enough #2 cyl would indeed be adjusted wrong. For instance, if you had TDC set for #1 and then just turned the engine 1/2 of a turn you'd have #2 cyl at TDC but would be on the overlap of the cam lobes and not on TDC of the compression stroke.

ETD:
Though I do admit I haven't done any work on 2 cyl. 4 cycle engines, I think I've got my math right.

 

[whynot162]

the tractor has been hard to start for years. After finding the leaking liners I was hoping that would cure the problem.
I will look at and follow that thread. Maybe I can work on this in the afternoon today

 

[whynot162]

here is a video of the tractor trying to start.
Tractor engine - YouTube
Also had the preheater hot, and fuel supplied, Still will not start.
It sounds to me like the valves are not closing at the right time? I also pulled the side cover off and the rods are seated in the lifters, and the lifters are all moving up and down fine.
Let me know what you think after listening to it. Sorry the starter is so loud.

 

[jacques54]

whinot162
As what i hear your engine is spinning like the compression release is ON and with a clear air wistle of unseated valves.

Do you back up the adjustment of compression release at least two turn before any valve adjustment?
When at TDC both rockers are free no binding on each cylinders?
I don't know if you have the right valve lash technic, but i'll explain a safe way to do it for all 4 cycle engine (i know).

Scribe a mark on the front cover near the crankshaft pulley.
Rotate that pulley in the apropriate direction, look the EX valve lift (close) and the IN begin to go down (open) you are very close to TDC.
Scribe a mark on the pulley near the one on the FC.
Then rotate the crank pulley 360° and aling both mark.
Now you are ready to adjust that cylinder. You should feel a slight drag on the feeler gauge when the jam nut is tighten.
Repeat the procedure for the other cylinder.

As a safety precaution, be sure to pull the engine stop before bigining.

Jacques