Any ideas as to why diesel engine wont rev past 2000RPMS`s?

[scottie]

Just to clarify you say you can vary pitch on propeller?
so you have a John Deere with variable pitch ?
you also have hydraulics driven equipment
is there a gearbox or other form of clutch between engine and variable pitch unit?

 

[Karlsenkystfiske]

Yess they follow each other.
Only position for operating gear.

 

[Karlsenkystfiske]

@JOHNPEET It is a John Deere 4045 TFM50 Pretty basic tractor. If it even has an ECU, then I have no idea where they put it

 

[JOHNPEET]

@JOHNPEET It is a John Deere 4045 TFM50 Pretty basic tractor. If it even has an ECU, then I have no idea where they put it

My advice at this stage would be to repeat the tests that you’ve previously done with the cables disconnected from the injection pump as per my most recent comment. From what I can determine from the info so far, if you disconnect the cables and run the engine using the injection pump lever directly, you can exclude any influence from anything external to the engine itself from affecting the engine speed. Test run in this manner on load and without load repeatedly in order to get some reliable data. The lever adjusts the speed setting of the injection pump. It’s the governor mechanism within the injection pump that determines how much fuel to inject based on its comparison between the speed setting (lever) and actual speed measured by the governor - all achieved via its inbuilt mechanical governor.

 

[jamie N]

Just a thought, how about removing the engine cables, and reinstalling them? This will mean not trying to find the fault, but to arrive at a solution.

 

[Karlsenkystfiske]

@JOHNPEET repeatedly mount and dismount the control cables? My last test was pretty reliable. No difference if it was my hand or control cable moving the injection pump lever. When crab season is done I plan to send the pump in for overhaul. It has only ran 5700 hours, but its leaking a little bit from time to time. It leaks more if the engine is run on max rpm.

 

[JOHNPEET]

@JOHNPEET repeatedly mount and dismount the control cables? My last test was pretty reliable. No difference if it was my hand or control cable moving the injection pump lever. When crab season is done I plan to send the pump in for overhaul. It has only ran 5700 hours, but its leaking a little bit from time to time. It leaks more if the engine is run on max rpm.

No, do repeated tests with the cables detached, without load and with load. My point being to build up some data to determine if the governor is working properly. Potentially, this would have been likely to be leading towards having the injection pump overhauled. In which case your proposed course of action is good. As well as sorting out your leaks, it will prove beyond doubt if the problem persists, that it can’t be the injection pump/governor. Obviously if the problem is resolved, then the cause must have been within the injection pump. Good luck with it and let us know how you get on

 

[scottie]

@JOHNPEET repeatedly mount and dismount the control cables? My last test was pretty reliable. No difference if it was my hand or control cable moving the injection pump lever. When crab season is done I plan to send the pump in for overhaul. It has only ran 5700 hours, but its leaking a little bit from time to time. It leaks more if the engine is run on max rpm.

Haveing the pump checked makes sense

 

[Alex_Blackwood]

@JOHNPEET repeatedly mount and dismount the control cables? My last test was pretty reliable. No difference if it was my hand or control cable moving the injection pump lever. When crab season is done I plan to send the pump in for overhaul. It has only ran 5700 hours, but its leaking a little bit from time to time. It leaks more if the engine is run on max rpm.

Another drip of information that was originally left out. The unimportant bit of evidence is what may solve the Crime!

 

[Karlsenkystfiske]

Just to clarify you say you can vary pitch on propeller?
so you have a John Deere with variable pitch ?
you also have hydraulics driven equipment
is there a gearbox or other form of clutch between engine and variable pitch unit?

Nogva 1131 gearbox has the pitch control intgegrated.
Hydraulic pump is connected directly to the camshaft.

Another drip of information that was originally left out. The unimportant bit of evidence is what may solve the Crime!

Yeah, well. Most of the time it does not leak at all. So its not what is causing it. But could be a part of the bigger picture!

 

[Alex_Blackwood]

Nogva 1131 gearbox has the pitch control intgegrated.
Hydraulic pump is connected directly to the camshaft.

Yeah, well. Most of the time it does not leak at all. So its not what is causing it. But could be a part of the bigger picture!

If your Sure

 

[ean_p]

To be fair K, I think John Peet has the right of this. If you remove the control cables and the issue persists then it is very likely that the issue is within the HP pump, having ensured that the fuel and air supply is both clean and free flowing. I note ( though it may be photo angle) that in the photo's you posted that the angle of movement of the pump control appears greater in the manual operation then it did in the cable operation. Are you sure they both came up against a stop and was that an internal or external stop?
For my two penneth I would check the stroke of the HP pump lever several times with the cable connected and physically disconnected as suggested by JP above to ensure that your getting full stroke consistently.
If this is OK and nothing of detriment can be seen or felt that positively applies to the HP pump then prior to removal of the HP pump for bench testing I would obtain a hand held tacho just to ensure that you are getting reduced revs etc. Yes you can no doubt hear it in the engine but that doesn't come over on here and the speed of drop of the tacho in your vid really was very very fast. The hand held agrees with the panel display then its a good chance you have an issue with the HP pump , ie governor spring or misplaced weight etc etc....
All the above as said on the assumption that there is free air and fuel.......

 

[Karlsenkystfiske]

Yeah I am sure. It is a external stop screw in both direction so easy to be sure One for low idle, and one for high idle.
Air I checked by removing the air filter. But I guess I am not 100% certain the TC is blowing as much as it should. I have no readings for boost pressure.
Does the handheld tacho connect to the same speed sensor as the tacho in the wheelhouse?
Cant say I have ensured that fuel is free flowing. How would I go about doing that? Pressurized air through all fuel lines?

 

[Karlsenkystfiske]

So fuel pump is out and sent in for overhaul.
Consider taking out the nozzles as well, but they seem to be quite stuck. I wonder if it would pose any danger to turn the engine whitout the pump attached? That should push the nozzles out

 

[Karlsenkystfiske]

Pump is overhauled and installed back in place. Turns out axle had a bit of wear and tear in it.
Engine will now do 2300 rpm`s with full pitch on the propeller! Only 200 RPM`s to go now

 

[Rappey]

Only 200 RPM`s to go now

Could that be the governor setting ?
This guy had something like a 28ft dory with huge engine and jet drive.
It barely got on the plane . Many things were looked at but no improvement.
One day another guy twiddled the governer setting and the boat took off !
Cant remember anything about rpms but im sure it was all within limits

 

[Karlsenkystfiske]

Pump is supposed to have been adjusted and tested by the workshop. Dont think I should fiddle with it

 

[ianat182]

May I offer my explanation regarding the throttle cable since a similar thing happened to me.
Do check that the cable outer is securely fixed and not allowing the outer to slide through the fixing; instead of moving the cable its self- even though it may rev straight away it really moves back through the outer fixing itself so negating the when it should be fixed advancement of the inner cable ti full rev state.
Your manual push of the lever will advance -only to return as the outer slides.

Ianat182