Twin 2008 Yamaha F350, Yamalube 10W-30, 99 hr OCI, 790 Total

[nicklx]

Decided to do an analysis on our workboat. Its a Parker 3420 XLD with twin Yam F350s. The work that we do involves a lot of idle time and low rpm cruising, I would estimate about half of the OCI hours are idling, but, when we do cruise I like to run it wide open. Boat gets about 250 hours a year since we have owned it. This is the first analysis it has had though, as I was starting to get concerned that the port engine was making oil. I change the filter every other oil change and cut them open and have never found any sludge or metal. This oil had been in for about 6 months.

 

[Brons2]

Viscosity is pretty low. Does the manufacturer approve of any other weights than 10w30? If it were me I'd try something thicker just so that the viscosity ended up in the 30wt range after 100 hours rather than the 20wt range.

[edit]
Well, that wasn't hard. Looks like they recommend 10w30 for most climates and 20w40 is allowed in consistently warm climates, NMMA FC-W spec recommended.
http://maintenance.yamahaoutboards.com/engine-oil-lube/

Here's some FC-W certified oils:
https://www.nmma.org/certification/oil/fc-w

Interestingly, it lists the approved Suzuki 10w40 as being manufactured by Motul. Motul also makes an oil called "MOTUL Outboard Tech 4T 10W-40" but when I searched Google I didn't find any sites in the US selling it.

I personally, just speaking of myself, might try the Suzuki 10w40...YMMV, of course. That seems like it would be available at a local Suzuki dealer.

 

[CT8]

Killer engines

 

[rubberchicken]

Try not to hit any sailboats.

 

[Johnny2Bad]

Yamalube is, in my experience, excellent oil. Interesting about the Motul Suzuki oil. A little fuel / oil dilution is common on marine engines.

 

[sunruh]

a flash of 335 is WAY more than 2.0%

a flash of 350 is WAY more than 1.3%

its clear the port side is not the same as starboard side.
the differences in Si,Zn,P,Ca is very interesting...differernt jugs or what?

maybe rings are more worn?

50hrs of idling is a lot
99hrs on a oci is a lot as well
half its life at idle, half at wfo...like a light switch

all in all very good reports...anyway to get that fuel dilution down?

 

[irv]

Originally Posted by Johnny2Bad
Yamalube is, in my experience, excellent oil. Interesting about the Motul Suzuki oil. A little fuel / oil dilution is common on marine engines.


I can no longer find the UOAs but back when I purchased my 4 stroke 08 Yamaha Vector snowmobile, the UOAs, and a couple VOAs, showed it as nothing special at all.

After I paid over $90 CDN for 3 ltrs of full syn 0W-40 of Yamalube and a Yamaha filter, is when, after asking myself what is so special about this oil, I found those UOAs and VOAs.
Needless to say it was the first and last time I ever used Yamalube in anything.

 

[CT8]

a flash of 335 is WAY more than 2.0%

a flash of 350 is WAY more than 1.3%

its clear the port side is not the same as starboard side.
the differences in Si,Zn,P,Ca is very interesting...differernt jugs or what?

maybe rings are more worn?

50hrs of idling is a lot
99hrs on a oci is a lot as well
half its life at idle, half at wfo...like a light switch

all in all very good reports...anyway to get that fuel dilution down?[/q They are boat engines.

 

[claluja]

Probably 5-10% fuel dilution - try Polaris next time if you want a real fuel dilution value (they will tell you if you are over 5%). All the idling time certainly doesnt help with the fuel dilution. Slightly high iron for a yamaha outboard (I usually get about 10 ppm iron per 60 hours in my F300s), so I'm guessing the fuel dilution is high enough that it could be leading to increased iron wear?? I'd shorten to 50 or 75 hours next time if they were my engines, which I've done with my F300s for this same reason.

 

[DoubleWasp]

With that vis, and that FD, there is no way I would do another 100 hour OCI on those engines. They shouldn't be given a minute over 50 hours on an OCI.