Yanmar YSM8 rebuild

[Wai_Tapu]

I've run into a bit of a problem rebuilding the YSM8 I bought last year /forums/images/graemlins/frown.gif Even though I took plenty of photos during the strip down, it would seem I missed one of the crank- and camshaft gears meshed together. As in the attached pic, each gear has a 0 stamped on one tooth. The manual helpfully says "align the timing marks" but does not specify if the crank 0 (upper right gear) goes to the left or right of the cam 0 /forums/images/graemlins/confused.gif

Anybody know the answer or can help in determining the correct alignment? Many TIA for any assistance.
Cheers, Richard

 

[uforea]

Is that timing mark on the lower left sprocket meant to line up with a different gear, ie one which comes from the bushing on the right.

Ted

 

[Niander]

good idea

 

[seacomm]

In my YSM8 handbook on page 2-35 it shows the 0 on the crankshaft gear between two 0 marks on adjacent teeth on the camshaft gear.

I cannot see the two marks on the camshaft gear in your picture only one. Are they further round out of sight or can the gear be put on back to front?

If you cannot find the marks you can check it with a circular protractor on the crankshaft to see where the valve lift occurs.

 

[Wai_Tapu]

Thanks for your responses gentlemen.
Seacomm, I have a rather blurry scan of the YSM8 manual but am unable to distinguish the marks on the diagram on page 2-35. Is there any chance you could email me a scan from your copy?
Cheers, Richard

 

[alexey]

Here is a much better quality scan of YSM series (YSM8 and YSM12) service manual: https://hisse-et-oh.com/system/assets/000/121/101/original/Service_Manuel_YSM_8_et_YSM12.pdf

All of the pictures are much crisper, none of the pages are missing. For example, engine cross section, and the tools chapter are there.