Periodic Maintenance - Yanmar Saildrive

May 12, 2020
51
Catalina 275 Sport 31 Quincy Bay
Hello. I'm starting to do some maintenance on the Yanmar on my 2016 Catalina. The engine has about 60 hours on it so there probably isn't much to do. What I've already done is changed the gear oil and engine oil (and oil filter). I also replaced the anode behind the propeller. A couple questions about other engine maintenance areas:
  • Internal anode (pencil zinc): I bought a replacement pencil zinc mainly because it was so cheap. Anyone have any ideas how frequently it should be changed? I tried to loosen the bolt with a 32mm socket wrench but couldn't apply enough torque with the awkward position. I'm assuming it can be omitted for now but I'm quite curious about it.
  • Fuel/water separator: I drained the bottom of the Racor and detected no water so I think I'm good there. Just to be safe, I will probably replace the filter anyway. I'm assuming I should turn off the fuel valve on the tank before I do this so as to avoid excessive fuel spillage? I believe there is only one shutoff valve located on the top of the tank and it needs to be turned perpendicular to the fuel line to shut it off. Also, do I need to prime the filter/separator and/or bleed the air out of the system after I replace the filter?
  • Sea water strainer: During the survey, it was noted that the plastic bowl was showing some cracks and I was advised to replace it. Does anyone know the manufacturer part number for this strainer? Any tips on how to replace it? Looks straight forward.
If you have any other maintenance suggestions for the engine, I'm all ears.

Thanks you!
 
Feb 21, 2013
4,638
Hunter 46 Point Richmond, CA
What Yanmar engine do you have? Is it a 2Y1M5?
  • Internal anode .........how frequently it should be changed? Suspect every 300 hours but check with your engine owner's manual
  • Fuel/water separator: I drained the bottom of the Racor and detected no water so I think I'm good there. Just to be safe, I will probably replace the filter anyway. I'm assuming I should turn off the fuel valve on the tank before I do this so as to avoid excessive fuel spillage? YES if you have one. I believe there is only one shutoff valve located on the top of the tank and it needs to be turned perpendicular to the fuel line to shut it off. Also, do I need to prime the filter/separator YES and/or bleed the air out of the system after I replace the filter? Depends, some Yanmars are self priming, otherwise YES. Follow you manual's instructions to bleed the air.
    Sea water strainer: During the survey, it was noted that the plastic bowl was showing some cracks and I was advised to replace it. Does anyone know the manufacturer part number for this strainer? Look for the stamp with the manufacturer and model number on it. Any tips on how to replace it? Simply remove it with a filter wrench. Looks straight forward.
 
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May 12, 2020
51
Catalina 275 Sport 31 Quincy Bay
What Yanmar engine do you have? Is it a 2Y1M5?
  • Internal anode .........how frequently it should be changed? Suspect every 300 hours but check with your engine owner's manual
  • Fuel/water separator: I drained the bottom of the Racor and detected no water so I think I'm good there. Just to be safe, I will probably replace the filter anyway. I'm assuming I should turn off the fuel valve on the tank before I do this so as to avoid excessive fuel spillage? YES if you have one. I believe there is only one shutoff valve located on the top of the tank and it needs to be turned perpendicular to the fuel line to shut it off. Also, do I need to prime the filter/separator YES and/or bleed the air out of the system after I replace the filter? Depends, some Yanmars are self priming, otherwise YES. Follow you manual's instructions to bleed the air.
    Sea water strainer: During the survey, it was noted that the plastic bowl was showing some cracks and I was advised to replace it. Does anyone know the manufacturer part number for this strainer? Look for the stamp with the manufacturer and model number on it. Any tips on how to replace it? Simply remove it with a filter wrench. Looks straight forward.
Thanks for the reply. Yes, I have a Yanmar 2YM15.
 
May 7, 2012
1,338
Hunter e33 Maple Bay, BC
Hello. I'm starting to do some maintenance on the Yanmar on my 2016 Catalina. The engine has about 60 hours on it so there probably isn't much to do. What I've already done is changed the gear oil and engine oil (and oil filter). I also replaced the anode behind the propeller.
I highly recommend that you get a copy of the Yanmar Service Manual (not Owner's Manual) for your engine. You can download a copy in pdf format from the internet.
Bare in mind that maintenance on diesel engines are based on calendar time and usage time. Although only having 60 hours on it, your engine is 5 years old and there is a fairly major schedule at 4 years.

Internal anode (pencil zinc): I bought a replacement pencil zinc mainly because it was so cheap. Anyone have any ideas how frequently it should be changed? I tried to loosen the bolt with a 32mm socket wrench but couldn't apply enough torque with the awkward position. I'm assuming it can be omitted for now but I'm quite curious about it.
I have the big brother Yanmar 3YM30 which does not have an engine anode. I would be surprised it the 2YM15 did.

Sea water strainer: During the survey, it was noted that the plastic bowl was showing some cracks and I was advised to replace it. Does anyone know the manufacturer part number for this strainer? Any tips on how to replace it? Looks straight forward.
One of the first things I did when I purchased my new 2012 boat was to change the R/W strainer. It was not ABYC approved for below the water line yet that was where it was located.
 
Jun 6, 2016
204
Catalina 275 Wilmette, IL
After I dropped the filter plug into a narrow glass I was capturing the fuel with, I added a petcock to make checking for water easier. I bought mine at McMaster-Carr, part no. 7910K83. For extra safety, I screw the plug into the end of the petcock. It looks like:

P1030793.JPG
P1030793.JPG
 
Mar 11, 2014
224
1057
How often do you change the Sail Drive Leg oil? Every few years or 250 hrs or what? Do you do in in the water or wait till you are on the hard?
 
Jun 6, 2016
204
Catalina 275 Wilmette, IL
The operation manual says, "Change the oil after the first 50 hours of operation or after long storage and every 100 hours of operation thereafter. Lube oil should be changed while the engine is still warm." Certainly sooner if you get water in it and the oil appears gray, milky. Of course, you will need to replace the seals if you are getting water in. I think the shaft seals are around 100 hours as well but I didn't see it in the manual. I have the seals, I just haven't done the work yet. You can do the oil change on the water or on the hard. Easier on the hard if you haul out anyway. PM me your email and I'll send you some goodies.

I believe the J/88 and similar group have had some discussion on the Yanmar SD20, so that may be a source of info as well.
 
Jul 27, 2011
4,988
Bavaria 38E Alamitos Bay
Use a breaker bar wrench with socket to remove the internal zinc. That's what I've had to do since day one!
 
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Nov 21, 2012
587
Yamaha 33 Port Ludlow, WA
An hour meter is a worthwhile maintenance investment if your don't have one.