Maintenance intervals

Aug 21, 2024
2
O’Day O’Day 30 WaterGate
I purchased my first sailboat over the summer, an ‘84 O’Day 30. Would anyone know the intervals at which to change the fuel filters? I believe I found 2. The oil is dark not what I’d have in my car. Is that normal?
I’m just not sure when everything was changed last and want to get out on the right foot.
TIA
Mark
 
May 17, 2004
5,414
Beneteau Oceanis 37 Havre de Grace
If you don’t know when things were changed I’d change them know so you have a good starting point. That would go for the filters, oil, antifreeze, and possibly transmission fluid. While you’re at it you could replace the raw water impeller an air filter. After you change the oil don’t be surprised if the new oil comes out black very quickly. That’s pretty routine for diesel engines.
 
Jan 4, 2006
6,948
Hunter 310 West Vancouver, B.C.
You might also consider finding your engine manual in the downloads of this site. Depending on your engine, air filters are worth a fortune but can be washed with dishwashing soap for a long life.
 
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jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
22,060
CAL 35 Cruiser #21 moored EVERETT WA
:plus: To what you read above. It is what I did. You need a known initial point for reference. Otherwise you’re running blind.

Now that you are a boat owner, welcome to the untold story. Maintenance on a boat is a constant activity interspersed with some recreational interludes.

Fuel Filters are at the least every 2 years or the number of run hours recommended in the engine manual. More often if you experience contamination in the fuel. If you don’t know the fuel filter is clogged your engine will tell you. “ Shame” and stop running.

The engine manual will provide recommended intervals.

Dark oil is a given. It’s not about the color. It is the contaminates that develop as the oil ages. I do mine yearly and if I will be making an extended cruise. I figure it is cheap insurance.

Pretty much everything is about regular inspection.
 
Jan 7, 2011
5,181
Oday 322 East Chicago, IN
The oil in diesels is generally darker (black) compared to a gas engine.

I change my engine oil and filter every other year. I am a location where the water gets hard in the winter, so my season is about 5 months. And I don’t motor much. Many people do it every year (or more if they motor a lot). I don’t think you mentioned what engine you have…Yanmar or Universal were common in the O’Day 30.

Fuel filter changes are typically dictated by how dirty they get. In my case, my fuel is clean and I went 5 years before changing my fuel filter. I finally changed them just because I was worried about the media breaking down due to age (they were fine and could have gone another 5 years I think).

But if your fuel / tank has some growth, sludge, etc. the filters (there are usually 2 - one on the engine and one between the tank and the engine) will need to be replaced more often. Some people have added a vaccuum gauge that will show when the filter is getting dirty and is working the fuel pump hard.

Good luck with the new boat. You will be able to get a lot of helpful info here on SBO.

Greg
 

degas

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Aug 14, 2023
11
Tanzer 29 Lake Ontario
I purchased my first sailboat over the summer, an ‘84 O’Day 30. Would anyone know the intervals at which to change the fuel filters? I believe I found 2. The oil is dark not what I’d have in my car. Is that normal?
I’m just not sure when everything was changed last and want to get out on the right foot.
Hey, congratulations!

What does your engine manual say about fuel filters? My Yanmar manual says fuel filter replacement every 250 hours, oil change every 300 hours.

I kinda ignore that by changing them more frequently. I only put about 100 hours/season on the engine. I change the fuel filters at the end of every other season. And I change the engine & transmission oil at the end of every season.

Overkill? I won't argue w/that. I'm no marine diesel expert, but the boat is on the hard for the winter and Canadian winters are hard on things. Besides, I ignore the engine otherwise. It's good to give it a once-over at the end of season to check for leaks, loose bits, and any other weirdness.

As for knowing the last time these things were done, like others have suggested, just change them now yourself so you'll be sure. And you'll get a bit of confidence by fussing with your engine in a non-urgent situation.

You might even keep a maintenance log, but that only pays off in the long run, and only if you're consistent about it.

Hope this helps.
 
Jan 22, 2008
51
Oday 30 Stamford CT
malighthill........I own a 1983 O'Day with the 16 HP Universal 5416 engine. I believe that Universal recommends the changing of the engine oil & oil filter, transmission oil & fuel filters annually. My boat has a factory installed Groco bronze fuel filter mounted adjacent to the fuel tank and a spin-on fuel filter on the engine. I change the Groco fuel filter (NAPA # 327) every year and the spin on filter only when I see dirt in the Groco Filter. The NAPA filters are cheap and I carry a bunch of them in case I get a problem with my fuel. When servicing the transmission Hurth recommends that you drain the transmission and refill it to the top of the transmission for the winter and then drain it down to the correct level when you are getting the boat ready for use in the Spring. The recommended engine oil for the 5416 engine is SAE 30 or a 10-40 HD diesel engine oil. I've been using synthetic oil in my engine since I purchased it in 1984 as the engine was running hot and I wanted the extra protection from a synthetic. I got the engine to run at the correct temperature by installing a larger diameter heat exchanger and I still use the synthetic oil. Lots of luck with your new boat. A friend of mine had a 1984 O'Day that was similar to the 1983 with the addition to a swim platform in the stern, enclosed storage area on the sides of the main cabin and the decks down below were fully covered by wood. His 1984 had a different engine than mine. He had a smaller Universal M-18, 14 HP engine with the same transmission as mine. Make sure you verify which engine you have before buying any parts for it.
 
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