Punsun V twin questions

[Kelly]

Hi I'm new to the site, My name is Kelly I live in the US, I'm building a tractor and bought a Punsun 25hp V twin, this has been a slow as time and money allow project, I have had the engine near two years, I had it running and driving this past winter, and was pretty happy with it, well now this week I had it running and ran as it did this winter, then it sputtered and stalled I thought nothing of it and did some other work to it, I mounted a fuel tank in the rear of the tractor and used a low pressure pump (2-4 psi) to pull fuel from it, installed a large filter all new line, wired up a new switch the one that came with it was crappy at best, I primed the lines hooked up the line to the pump on the engine cracked the injector lines at the heads and cranked it, not wanting to burn up the starter I did this a few times with no fuel coming out, I held the comp. release open on both heads and cranked more, nothing, I then pulled the parts the lines hook to out of the pump, not sure what they are, I made sure the shims all got put back when reassembling it, still nothing I did this a few times checking things over seeing how it worked the best I could, then it fired up, I thought all was good till it ran away, no throttle control at all, I capped the intake to stall the engine, I took the pieces back out of the pump and made sure the pieces in there moved with the throttle, and they do, geared rings and a rack with teeth on it, all move freely as the throttle is moved, I have started it a few times after that with the same problem, I know it is getting WAY to much fuel, it runs wide open and pours out black smoke, the engine only has about 15 or 20 min. of run time on it.
I was hoping someone here might have a clue where to start?? I did some searching but found little info, I know very little about diesels but have built many V8 car engines for my race cars and my drivers, could it be pump timming?? if so how do I check it or set it, Sorry for the long winded story.

[BertTrack]

Hi Kelly,

That's not a long story at all!

Timing may be off but shouldn't overrule the rpm regulator.

Maybe i'm a silly bugger but, when you put things together the engine wasn't running i take it. So the fuel setting at 00 rpm's should have been full throttle? (so it starts to give less and less fuel as it reaches idle speed)

Depending on how it regulates the amount of fuel either the pump control must be turned to give the most fuel or the "relief" valve has to be just fully closed. When setting it up.

Thought i'd mention it since i made that mistake with my yanmar one time.

[Kelly]

Well I tore things apart to see what did what, forgive me for not knowing the names of stuff I'll try to explain as I go, in the top of the pump is two bodys that the lines hook to, inside them is a plunger that moves up and down with the camshaft, the plungers have a spiral cut grove in them, and are rotated by the gears around them as the throttle is moved the spiral lets more fuel in the port in the side of the body the line hooks to, so I turned the bodys as far as they would go for less fuel, (they have slotted holes that the hold down bolts go through) well it would not start so I turned them all the way the other way, it fired right up, and I have throttle control, talk about happy.
Now the next issue if I idled it down it knocked BAD, but sounded like only one cyl. so I gently pressed one comp. release at a time just a tiny bit, and the first cyl. made no difference the next one the knock went away, so I knew what cyl. it was, not knowing diesels I guessed the knock was to much fuel, so I turned the body in the pump for that cyl. to allow less fuel , and it worked the knock all but went away, my question is how do I set the fuel flow/timing on this engine?? I'm guessing like I did, but I can't do that when it is running as the line is tight and will not let me turn the thing what ever it is? and on top of that I really don't know where I would want it set, I don't want to screw things up, any help would be great.
Oh and if you could tell me what the names of the stuff is so I don't feel like a moron.

[coachgeo]

DIESEL's MUST KNOCK!!!!! if it is not knocking then the timing of injection and combustion is off and you will coke your engine (carbonized unburnt fuel on the rings, piston head etc.) That is one issue with people who run Veg. Oil fuels..... they rave about how their engine got quieter.... which is BAD. That means they need to retime the Injection pump to the characteristics of veg oil. (the fuel's inherent time of combustion for example)

[Kelly]

It still knocks, but it was sounding like one rod was about to come out of the engine, it was VERY violent, and every time that cyl fired it shook the motor VERY hard, now it has a normal knock to it, and both cyl. sound more even, I just would like to time it correctly, but do not know how.

[DieselFly]

You must do a static timing check. If you look the top of the output fittings on the fuel pump are slotted. This will allow you to change the fuel timing about 3 to 3.5 degrees. The Pusun's and all the other Chinese diesels that I have screwed with have timing marks on the flywheel. They use BTC for the zeroing out the pointer. Don't keep playing with it as I knocked a rod bearing out of mine doing it by ear. It has been proven time and time again that they come factory direct not correctlly timed. I put a second engine in mine after I hurt the first one and it broke a whole bunch of stuff from vibration. The timing was 24 degress on one cylinder and 19 on the other. The book called out 18 degrees. If it runs they ship it so check it before you kill it!!!!