Yanmar transmission dipstick

Apr 22, 2011
865
Hunter 27 Pecan Grove, Oriental, NC
If you have a GM series yanmar with the kw tranny and your dipstick has the yellow plastic threads you might be interested in this. I have had the threads stripped to the point that the dipstick needed replacing. I'm pretty careful when threading being that the soft plastic is going up against an aluminum housing. After a little research, I found the problem to be fairly common.

To avoid plastic altogether I found an iron drain plug that would fit but I gave up on trying to drill a 1/16" breather hole in it. I finally found an aluminium plug made in Germany for Porches. See link: http://www.5150motorsport.com/oil-drain-plug-m18-x-1-5mm-900-219-020-31.html. It's around $8 with shipping. Fits perfectly and was easy to drill the breather hole. Came with aluminum gasket. Even if you don't need one now would be useful as as a spare. I kept the old stick for measuring.
 
Oct 29, 2005
2,355
Hunter Marine 326 303 Singapore
Heritage,
Thank you. Had mine broke at thread like you said. Replaced with new but had this constant fear whenever i had to replace the gear oil. Aluminium dipstick plug is the way to go :D Thanks again.
 
Dec 19, 2006
5,809
Hunter 36 Punta Gorda
I had same thing happen and replaced with new and now am very careful and take my time and do not over tighten
it and so far good,just go slow and easy and don't need to take it in and out too much.
Nick
 
Apr 22, 2011
865
Hunter 27 Pecan Grove, Oriental, NC
After about 20 hours of run time using the aluminium plug with 1/16" hole drilled in the top, I found that a substantial amount of oil was escaping through the hole. I'm either drilling a smaller hole or attaching some type of standing pipe with a breather hole cut in in the side. The top end will be capped. Any thoughts other than the obvious: Just buy a new!
 
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Dec 19, 2006
5,809
Hunter 36 Punta Gorda
I purchased a new one a few years ago and now just take my time taking it in and out and mot over tighten it too much and so far very good
 
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Apr 22, 2011
865
Hunter 27 Pecan Grove, Oriental, NC
Follow-up on my original post. Because the aluminium plug was spitting out some oil even after drilling a smaller breather hole, I decided on a different approach. I took the Porche plug and drilled a hole about 1/64" smaller than the original Yanmar dipstick measuring probe. Then cut off the orange plastic threads with a hacksaw. Taped the dipstick through the aluminum plug until it bottomed out. Put some JB Weld between the surfaces before closure. Picture shows it better than I can explain. Basically, I'm replacing the plastic threads with aluminum ones.
IMG_20170302_122338.jpg
IMG_20170302_122057.jpg
 
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copaco

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Sep 30, 2020
2
Mirage 27' Saint-Jean-Port-Joli,Qc
I'm far from my sailboat and Yanmar SB8.I would like to adapt good bronze pump from Perkins and looking for size of dipstick tube.I also have to access engine to stop.???
 
Sep 11, 2019
126
Hunter 49 2 San Diego,Ca
Hey guys I know this is an old post but I’m sure you guys can steer me in the right direction I’m looking at that dipstick and all I see is a line at the bottom and a hole at the top how do you measure the oil?
Also my manual says Marine Gear Lube viscosity 20 or 30, Is this the same as regular oil?
Thanks
Scotty Sailor
 
Apr 8, 2011
768
Hunter 40 Deale, MD
Hey guys I know this is an old post but I’m sure you guys can steer me in the right direction I’m looking at that dipstick and all I see is a line at the bottom and a hole at the top how do you measure the oil?
Also my manual says Marine Gear Lube viscosity 20 or 30, Is this the same as regular oil?
Thanks
Scotty Sailor
Save yourself some heartache and get one that is an upgrade AND works out of the box. I know, its not $8, but its the last one you'll ever buy:

Cariblue Marine
 
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