Fuel Octane for new Volvo Penta?
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HairyGorilla
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Fuel Octane for new Volvo Penta?
Hi - any suggestions on which octane to use on my new 2020 R5 Surf w/ VP350 engine?
At our marina they offer 90 octane "with up to 10% ethanol" or 93 octane without ethanol. There is almost a $1 difference per gallon so I'm curious if anyone has any feedback? I believe 90 is recommended however I'm not sure if the ethanol plays into the decision and the extra cost could be justified?
Thoughts?
At our marina they offer 90 octane "with up to 10% ethanol" or 93 octane without ethanol. There is almost a $1 difference per gallon so I'm curious if anyone has any feedback? I believe 90 is recommended however I'm not sure if the ethanol plays into the decision and the extra cost could be justified?
Thoughts?
- AsLan7
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Re: Fuel Octane for new Volvo Penta?
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87 is the recommended Octane for the 5.3L 350 horse Volvo Pentas. Yours being the VOLVO PENTA V8-350-CE/DPS.
"Despite this high compression ratio, all of these new engines can operate on 87 octane gasoline."
If you are using your boat constantly (more than a couple times a week) then I would opt for the 90 Octane grade with up to 10% ethanol. If you go longer than that and don't fill up often, then I would pay extra to keep the evil ethanol out of my boat's belly.
Ethanol fuel can phase separate quite easily especially during longer store-ups and humid environments. Once it phase separates, the only way to get it out of your fuel tank is via a siphon.
The extra money you pay now may be worth it depending on how you use your boat.
.
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87 is the recommended Octane for the 5.3L 350 horse Volvo Pentas. Yours being the VOLVO PENTA V8-350-CE/DPS.
"Despite this high compression ratio, all of these new engines can operate on 87 octane gasoline."
If you are using your boat constantly (more than a couple times a week) then I would opt for the 90 Octane grade with up to 10% ethanol. If you go longer than that and don't fill up often, then I would pay extra to keep the evil ethanol out of my boat's belly.
The extra money you pay now may be worth it depending on how you use your boat.
.
.
.
2002 Cobalt 262
&
2005 Cobalt 263
496 MagHO
(sold )
Erie, PA
Currently boatless (for now)
will fly for food
(CChat moderator)
&
2005 Cobalt 263
496 MagHO
(sold )
Erie, PA
Currently boatless (for now)
will fly for food
(CChat moderator)
Re: Fuel Octane for new Volvo Penta?
Great stuff!AsLan7 wrote: Mon May 04, 2020 2:58 pm .
87 is the recommended Octane for the 5.3L 350 horse Volvo Pentas. Yours being the VOLVO PENTA V8-350-CE/DPS.
"Despite this high compression ratio, all of these new engines can operate on 87 octane gasoline."
If you are using your boat constantly (more than a couple times a week) then I would opt for the 90 Octane grade with up to 10% ethanol. If you go longer than that and don't fill up often, then I would pay extra to keep the evil ethanol out of my boat's belly.Ethanol fuel can phase separate quite easily especially during longer store-ups and humid environments. Once it phase separates, the only way to get it out of your fuel tank is via a siphon.
The extra money you pay now may be worth it depending on how you use your boat.
.
.
.
2008 272 , 496 HO fo SHO
California Delta
Table Rock Lake
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- Jeeper
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Re: Fuel Octane for new Volvo Penta?
I always use non ethanol gas if there’s a choice. The way I see it is the the cost of gas one of the least expenses of a boat. When the boat costs 130K. 30 dollars a day difference in the cost of fuel is money well spent to avoid problems. Besides that non ethanol gas is more efficient so you will use less gas.
2019 R5 Surf 380 VP.
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Stagdad
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Re: Fuel Octane for new Volvo Penta?
I have the VP 300 (same engine, different ECU) and I use 90 rec no alcohol. No problems thus far. The extra cost to keep potential ethanol problems at bay is worth it to me.
Stagdad(Brian & Linda)
220s V8 300VP
Home Port Northern KY
Away Port Lake Cumberland / Dale Hollow
220s V8 300VP
Home Port Northern KY
Away Port Lake Cumberland / Dale Hollow
Re: Fuel Octane for new Volvo Penta?
I had a 2015 with the prior gen VP 5.0. I bought the boat used and had zero issues with the first tank of gas. I put 87 octane in the next tank. After cruising and shutting it off for lunch it was very hard to restart. I had to crank it a while. Next tank was 90 zero ethanol and it would fire right up every time. Had to put some 87 in as I was running low at one point after that. Had more hard starting. Zero ethanol from then on and zero problems.
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sailor55330
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Re: Fuel Octane for new Volvo Penta?
Ethanol is baaaaadddddd stuff. Personally, always pay more for no ethanol!!
- jhnmdahl
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Re: Fuel Octane for new Volvo Penta?
If I knew I was going to burn through the gas that weekend (or maybe over the next week or so?), I'd probably use the 90 octane with ethanol. But, I rarely burn gas that fast, and personally always buy the ethanol-free gas at a premium.
Cobalt says 87 octane is fine, and all the VP engines will run fine on it, but Volvo Penta has stated a handful of times that many of their modern engines can advance timing a bit and take advantage of higher octane up to around 90 if it's available. I wouldn't sweat the octane number, or pay much extra for it alone.
John
Cobalt says 87 octane is fine, and all the VP engines will run fine on it, but Volvo Penta has stated a handful of times that many of their modern engines can advance timing a bit and take advantage of higher octane up to around 90 if it's available. I wouldn't sweat the octane number, or pay much extra for it alone.
John
Administrator of the www.cobaltchat.com Cobalt boats community forum
2015 210 (Volvo Penta 5.7L V8-225)
2015 210 (Volvo Penta 5.7L V8-225)
- Krob1114
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Re: Fuel Octane for new Volvo Penta?
We're lucky enough to have mid grade, no ethanol at our marina. Not problems of any kind on Cobalt after two full boating seasons.
I've read the the ethanol and gasoline only separate when exposed to air. Boats made after 2012 are not vented the same way was as older boats meaning less chance of separation. The first time we had problems with boat running, it was fuel filter full of ethanol that had separated. That was when we were still filling up at gas stations. I would not be afraid to use the 90 octane because it wouldn't sit in our boat long. I will not be using 87.
I've read the the ethanol and gasoline only separate when exposed to air. Boats made after 2012 are not vented the same way was as older boats meaning less chance of separation. The first time we had problems with boat running, it was fuel filter full of ethanol that had separated. That was when we were still filling up at gas stations. I would not be afraid to use the 90 octane because it wouldn't sit in our boat long. I will not be using 87.
2019 Cobalt R3 @ Greers Ferry Lake, AR
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jma2@fuse.net
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Re: Fuel Octane for new Volvo Penta?
I couldn't agree with you more. Well stated. The same can be said for those boat owners who haul gas to their dock from the gas station in 5 gal cans to save a few bucks in gas over going to the marina. A friend of mine has a brand new MC boat ($150k), and yet he hauls gas to his dock 5 gallons at a time. Go figure.Jeeper wrote: Wed May 06, 2020 9:36 pm I always use non ethanol gas if there’s a choice. The way I see it is the the cost of gas one of the least expenses of a boat. When the boat costs 130K. 30 dollars a day difference in the cost of fuel is money well spent to avoid problems. Besides that non ethanol gas is more efficient so you will use less gas.
2016 CS3
Volvo 280-G
Cincinnati, OH/Norris Lake, TN
Volvo 280-G
Cincinnati, OH/Norris Lake, TN
Re: Fuel Octane for new Volvo Penta?
Been using ethanol fuel for 25 years. Never an issue.
Ethanol issues get so blown out of proportion
Ethanol issues get so blown out of proportion
2017 R5 350HP Mercruiser Bravo III
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South Lake Tahoe, CA
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- Big Block Power
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Re: Fuel Octane for new Volvo Penta?
Yep I put ethanol in my new snow blower once and it ran like crap. Never Again in any of my toys.
My boat only saw ethanol once and that was at a gas station at trl. I added treatment and couldn't wait to get that crap out of my boat. Nope nope never Again.
My boat only saw ethanol once and that was at a gas station at trl. I added treatment and couldn't wait to get that crap out of my boat. Nope nope never Again.
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