Yanmar YSE8 injection timing problem

[escapism]

Having owned a boat with a YSE8 for some 30 years, the last thing I would suspect from a 'failing to start' issue would be the engine timing, and I cannot see how it would change in the way you seem to think. So you've bled the engine to the top of the injector, but have you checked the spray pattern from the injector itself?

 

[Jankops76]

Am I daft, which is very possible, or is the pump drive ring, the bit you have arrowed in red, the opposite way around in your original photo to the diagram above?

In your photo it appears to get greater width as it rotates clockwise but in the exploded diagram it appears to get greater width as it rotates anti-clockwise?

If it is then it would completely mess up the timing, as you are seeing

View attachment 184368View attachment 184369

You're definitely not a daft I had also turned the other way around, but then the TD sign was far away. Those gaps are different, on different sides
I need to open up my spare YSE8 motor which is for parts, then I will know what is inside it. It is possible that the previous owner put in the wrong part, but it looked like no one had changed it because the gasket was very old. But it's still an option

I will check during the holidays, There may be gaps on both sides, I mean the axles. But then the gear position also changes. I have to watch it on the spot! It already looks good, the diagram shows that it should be the other way around.

 

[Jankops76]

Having owned a boat with a YSE8 for some 30 years, the last thing I would suspect from a 'failing to start' issue would be the engine timing, and I cannot see how it would change in the way you seem to think. So you've bled the engine to the top of the injector, but have you checked the spray pattern from the injector itself?

I checked, it's a nice mist, it sprays straight a bit wide.

 

[Steve_N]

I think its possible its just the wrong way round - try it and see?

I think you've hit the nail on the head DinghyMan.
That camshaft pulley is rotating anti-clockwise and that pump cam profile is all wrong, it should be exactly the opposite i.e. a rising ramp then a sudden drop off once the injection has taken place. The parts diagram seems to clearly show it the other way around.

Pic: pulley rotations arrowed in green.

 

[garymalmgren]

Hello from Sweden. I am new to boating.
Comfort30, Yanmar YSE8 engine turns but does not start.

I have a couple of simple questions that might clear things up.
Did this engine run and then become unable to be started?
Was this engine rebuilt and THEN wouldn't start?

gary