Decompression shafts

[ptl]

My 147D is leaking oil at one of the decompression shafts that enters the valve cover. These shafts are held in place by pins. What is the best way to remove these pins in order to remove the shafts and replace the O-rings?

 

[MJPetersen]

Hi welcome to TBN. I am really surprised that someone has not responded to your question already. Usually there will be 2 or 3 knowledgable people responding to these kinds of questions.

I do not have a 147 and am not sure how the shafts are released, however I do know that Yanmar uses lots of spring roll pins. If this is what you are talking about then you need to carefully drive these out with an appropriately sized pin punch. You actually can get pin punches with a small nipple in the center to aid in centering the punch and holding it centered.

I take it that you already have the valve cover off and are wanting to get to the o-rings to replace them?

Maybe this will bump your request to the top and someone more knowledgeable than I can give you a better answer.

Mike

 

[ptl]

Thank you for the response Mike.

I am also suprised that there was not any advice regarding this problem. I assume that other Yanmar models use the same system for decompression. Maybe I am wrong.

I really appreciate your tip on the punch with a small nipple in the center. I was not aware of that type of punch.

I did have the valve cover off. It looks like the pins were originally punched in from the top down. By examining the inside of the valve cover, it does not appear that they can be punched back out from the inside. In other words the holes for the pins do not extend to the inide of the valve cover. That is the problem I am having.

Also I was wondering if these are special O-rings since they are on a rotating shaft.

Phil