Oil oil oil oil oil?????

I think the biggest consideration for the proper oil is that Merc recommends a NMMA FW-C rated oil. I use Merc's synthetic blend and on my next oil change considered switching to all synthetic. Amsoil does have a FW-C approved oil so it goes on the list of oils to consider. My engine's way out of warranty but I'll still treat her like she's new.
I change the oil every 30 hours anyway I should be OK with the blend or full synthetic.
 
Nehalennia said:
I think the biggest consideration for the proper oil is that Merc recommends a NMMA FW-C rated oil. I use Merc's synthetic blend and on my next oil change considered switching to all synthetic. Amsoil does have a FW-C approved oil so it goes on the list of oils to consider. My engine's way out of warranty but I'll still treat her like she's new.
I change the oil every 30 hours anyway I should be OK with the blend or full synthetic.
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I am curious as to why you are changing your oil every 30 hours? It is overkill, by a long shot. Send an oil sample in for analysis after 30 hours and you will understand what I am talking about. I put 80-100 hours on my Cats each season, and the samples come back in excellent condition. The oil looks black from the soot, but property wise, it is still very strong. Again, I run Rotella, 15-40.
 
AMSOIL has extened drain intervals which will allow you to change the oil once a summer.
 
Boatingnut said:
I am curious as to why you are changing your oil every 30 hours? It is overkill, by a long shot. Send an oil sample in for analysis after 30 hours and you will understand what I am talking about. I put 80-100 hours on my Cats each season, and the samples come back in excellent condition. The oil looks black from the soot, but property wise, it is still very strong. Again, I run Rotella, 15-40.
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First, you have diesels, with much, much better filtering capabilities. You run Rotella as it's designed for diesels. Rotella is not FW-C rated, which is not a requirement for diesels.

Second, I have just adapted that routine because the boat sits for periods at a time and I believe (even though from now until Sept we are using her every weekend) she still sits for 4 days in a row with no movement. Even though the FW-C oil is made to deal with the condensation and rusting inside the engine, this minimizes the exposure to that moisture.

Third it's only 3 or 4 changes a year usually. One in the spring (I'm due, I've put on 30hours since Christmas), one in June and then a third in Sept/Oct.
I put abour 120-140 hours a year on her.

Yeah it may be overkill, but in the big scheme of things oil is cheap. It runs at 3500 RPMs for 1.5-3 hours a trip so the pampering is worth it.
 
Thanks for the response. Not sure my filtering system is superior to yours. I use NAPA Gold oil filters, a pair each engine. Nothing special. You should send in an oil sample, just for giggles. You will at least be pleased to know that the oil you pull is still in excellent condition. I agree, for you, oil changes are cheap enough.

One question, though. I change oil in the fall, and lay up for 6-7 months. I don't change the oil in the spring, run it all season, change it in the fall. I send samples every year to Blackstone. No corrosion, no rust. Hmmmm. You sit for four days at a time. Wonder what the difference is?
 
Don't tug on superman's cape, don't SPIT in the wind, don't pull the mask off the ole lone ranger, and don't participate in boat oil threads.
 
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Boatingnut said:
Thanks for the response. ..........Hmmmm. You sit for four days at a time. Wonder what the difference is?
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Yeah, I'm not worried about the 4 days. I'm just covering all bases and I'm set at regular intervals. The engine is just running at high RPMs for long periods under load. It's cheap insurance. Lot's of stuff I do on my boat is overkill, but it's cheaper than heavy repair bills, which I don't want and cannot afford.
 
ok, ok spit it is.
 
Boatingnut said:
I am curious as to why you are changing your oil every 30 hours? It is overkill, by a long shot. Send an oil sample in for analysis after 30 hours and you will understand what I am talking about. I put 80-100 hours on my Cats each season, and the samples come back in excellent condition. The oil looks black from the soot, but property wise, it is still very strong. Again, I run Rotella, 15-40.
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True. However, Todd is putting 120 hours per year on his engine and it's 10 years old, that's 1200 hours.

My mechanic taught me a good rule of thumb is to consider 1 hour on a marine engine as equal to 100 miles on a car engine. So Todd is following a 3000 mile oil change and in car miles he has 120,000 miles on it. Any major oil related issues Todd?

It would be interesting to see what the top end looks like.
 
dpmulvey said:
True. However, Todd is putting 120 hours per year on his engine and it's 10 years old, that's 1200 hours.

My mechanic taught me a good rule of thumb is to consider 1 hour on a marine engine as equal to 100 miles on a car engine. So Todd is following a 3000 mile oil change and in car miles he has 120,000 miles on it. Any major oil related issues Todd?

It would be interesting to see what the top end looks like.
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Well my boat has an interesting history. I bought it in Dec '07. The original and only owner only put 94 hours on it. Yeah, it lived on Lake Union in Seattle and every once in awhile would grab a few beers and a bottle of wine and run idling laps in this small lake. He made one trip to the San Juan islands and for the most part it sat for it's 7 years when I bought it.
Here she sits when I first saw her.
PICT0010.jpg

Once I bought it the outdrive was completely corroded and the PO agreed to replace it. I had the engine removed for that and checked out thoroughly. Mechanically, she was like new, but cosmetically needed attention.
PICT0006.jpg

PICT0008.jpg

Changed the oil then obviously. (I also found a receipt from '03 on board where the PO replaced the drive after 52 hours. So in it's 7 years and 94 hours it was going on it's 3rd outdrive. Very hot marina on fresh water)
Since then I've changed the oil every 30 hours. I don't have any oil issues, however I have never had the oil analyzed but she runs like a sewing machine.
 
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I typically change at around 50 hours - 75 hours max. But when winterized I have fresh oil in for the winter. I use the Synthetic Blend and debated on the Full Synthetic - but decided not much benefit given the hours I put on a season. But it has been mentioned before - other things people often over look is impellers for the engines. While mine showed some wear and you could see how they are starting to crack they were still in decent shape. If you change oil regularly - I think failure from oil is unlikely - but overheating can lead to other expensive engine issues. On my dock - I am amazed when replacing impellers last week - so many folks on my dock would come and say - you overheating? No preventive medicine. Then the next comment - I have never changed my impellers... Were yours bad?...
 
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I'll second the Amsoil recommendation. I'm running the 10w40 Marine oil in both of my engines and they are running great with consistent pressure on both. For the API licensing and/or certification - Amsoil is licensed on most of their oils which does not include the Marine oils but does include most of their automotive oils. They are also API certified on 5w20 and 5w30. I run their Ea filters (synthetic media material) and the oil for an entire season which is between 90-100 hours for me. I pulled the valve covers at the end of last season due to a slight leak from one of the gaskets and it was clean with no indication of any buildup.

License info: http://eolcs.api.org/DisplayLicenseInfo.asp?LicenseNo=0995
Certification info: http://eolcs.api.org/DisplayLicenseInfo2.asp?LicenseNo=0995

The Amsoil Marine oils are FC-W certified which means they have gone through the appropriate minimal tests outlined by NMMA.

Oil choice really comes down to a personal preference. I don't think you'll see an oil related failure on any of the modern oils - they even offer recycled oils which are filter, refined and new additive packages added. I think the chances of water related engine problems or failures is MUCH more likely!

Along with the recommendation earlier in this thread to look at bobistheoilguy - do some research on the oil filter as well. There are significant differences in the way they are designed and manufactured as well as the types of materials used. A low end oil filter can collapse and restrict oil flow which reduces oil pressure. Not a good place to save a couple of dollars.
 
skolbe said:
I typically change at around 50 hours - 75 hours max. But when winterized I have fresh oil in for the winter. I use the Synthetic Blend and debated on the Full Synthetic - but decided not much benefit given the hours I put on a season. But it has been mentioned before - other things people often over look is impellers for the engines. While mine showed some wear and you could see how they are starting to crack they were still in decent shape. If you change oil regularly - I think failure from oil is unlikely - but overheating can lead to other expensive engine issues. On my dock - I am amazed when replacing impellers last week - so many folks on my dock would come and say - you overheating? No preventive medicine. Then the next comment - I have never changed my impellers... Where yours bad?...
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The 6.2's in Saint Max are a stroked version of Todd's 5.7. The raw water pump is the lower left or his pic. I swear the damn thing was engineered and designed by a sadomasochist.

I'm still fighting a pinched nerve in my back where I went into the ER with notes from this site just to see if it was a DIY for me. At 6'4" and 215 pounds....it's not even close.

I don't know what is going to cost more, the impeller replacement or the chiropractor.
 
What is everyone's opinion on the Royal Purple oils? I'm still using the Mercruiser sythentic blend in my twin 454's, but I'm thinking better options must exist....
 
If I was running custom high output engines in an offshore race, I think Royal Purple would be one of the top choices. It's just plain over-kill for factory engines used under normal boating conditions......not running 5,000 plus rpms for many hours sustained operation. MerCruiser tested a factory 350/260hp at WOT for days (non stop) with only stopping for fuel and the engine never failed with standard dino oil, Mike.
 
As with every boat I've had, I use the manufacturers recommended oils and I change it according to how hard I run the boat... usually it's around 50 hours... sometimes a bit more if I drive like an old lady a lot (which I do sometimes). Any more frequently is not necessary.
20 hour oil change intervals? That's just the obsessive compulsive disorder having a little flare-up! There's no reason behind it.

There's not a lot of magic involved.
 
Mazola. It's high in polyunsaturates.
 
Have had no problems whatsoever with a quality "dino" Straight 30W, 40W, or the standard-grade Merc 25W-40.

The "extended drains" argument doesn't exactly hold water as most folks who boat where winter exists just change their oil annually anyway at lay-up.
 
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