Yanmar gearbox flange

[Norman_E]

I have a Yanmar 4JH2 series engine with a Kanzaki gearbox. I need to make an extractor to pull the shaft flange off, but I am in the UK and the boat is in Turkey. Can anyone with a similar engine please measure the flange diameter, which I think is about 4 or 4.5 inches, and if possible give me an idea of the pitch circle diameter of the four bolts?

EDIT: I think I found the answer by looking at R&D marine's coupling selection guide, which shows that the KBW 20 & 21 gearboxes (I can't remember which mine is) have a 5 inch flange with 4 holes at 100mm PCD, so I will make an extractor on that basis, but with slots in case the PCD is different.

 

[lpdsn]

I've a PDF of the Yanmar manual for the KBW20 & 21 gearboxes. No measurements, but there are torque settings for the output shaft coupling. Let me know if it is of any use to you and I can e-mail it. It's about 1.2MB.

 

[Norman_E]

Thank you for the offer. Fortunately I don't need the manual as I don't need to strip the gearbox, just get the coupling off the shaft so that I can withdraw it and change the cutless bearing without having to dismantle the Maxprop.

When I have made the puller to get the coupling off I will post a photo on here.

 

[lpdsn]

When I have made the puller to get the coupling off I will post a photo on here.

Thanks. I may have to do the same in a few years.

 

[Norman_E]

Here is the puller, hot off the milling machine. It consists of a 5 inch length of 1.25 inch by 7/16 inch steel with a central hole tapped 12mm, and two 10mm wide slots to cope with bolt centres of up to 105mm.

 

[lpdsn]

Thanks