www.iFourWinns.com

Hey guys,

My owners manual for our 2001 328 Four Winns is on the boat. If I recall correctly I believe the manual states "midgrade gas preferred" and I have always tried to put at least 89 octane fuel in. Anybody have any other info on fuel octane requirements for our boat year?

We are heading out on vacation this Friday and heading up Lake Huron (Great Lakes in Ontario, Canada) I need to stop for fuel about have way up to Tobermory. Problem is the normal place I hit for fuel (Port Elgin) due to construction at the marina does not have fuel available and the other closest marina nearby that makes sense for us to stop in at is Kincardine which only sells regular 87 octane fuel. I probably won't have much 89 octane fuel left in our fuel tanks when I arrive in Kincardine so if I fill up there what I would then have is mostly 87 octane in our tanks.

Is it worth considering buying some octane boost stuff for this 87 fill up, or try to find fuel elsewhere of midgrade or would you feel running with 87 octane is absolutely no issue at all? Thoughts?

Thanks,
Mike.

_________________

Current Boat
- 2001 Four Winns 328 Vista "Hour Decision"
- 2010 310 Mercury Inflatable

Previous Boats
- 30' Doral Prestancia
- 25' Doral Citation

I run 87 in our GXI's all the time no issue!

_________________
2001 328 Vista "Nauta Dream 2"
AB Inflatable 10AL "Little Dreamer"
2000 248 Vista
1997 225 Sundowner


Mike

Enjoy your trip! I'll be approx 60 miles to your east on the other side of Georgian Bay.

I have never intentionally run anything but 87 with no issues.

_________________
2004 - 288 Vista
Twin - 5.0 Volvo Penta GXi DP

Thanks guys for your feedback. When I get down to the boat this evening, I plan on reviewing the wording used in our owners manual for the recommended octane level of fuel to be used. To be honest, if mid grade was available in Kincardine I would of just filled with that and be done. I'll be stopping in Michigan for a fill up on way back just to take a little sting out of the total gas cost (cheaper mid grade fuel in the US as compared to Canada) for our approximate 500 mile boat vacation.

_________________

Current Boat
- 2001 Four Winns 328 Vista "Hour Decision"
- 2010 310 Mercury Inflatable

Previous Boats
- 30' Doral Prestancia
- 25' Doral Citation

Sounds like a great vacation, Enjoy!

_________________
Current:
2000 Sea Ray 380 Sundancer "still Livin the Dream"

Past
2002 268 Vista 5.7 GXI "Livin' the Dream"
1996 Rinker 192 Captiva. "The Simple Life"
1999 Yamaha XLL 1200 Waverunner.
1976 Mercury Marquis tri hull 120 hp

We also run 87 pump gas a lot when we trailer without issues with our 5.7 GI. On our North Channel trips we try to tow as close to empty as possible and then fill up the tank with 87 right before the border crossing, then again before launching when we get home.

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Our Boating Blog: http://ben-dana.blogspot.com/

2005 268 Vista "Sea Pickle II"
1979 AMF Alcort Puffer
Previous:
2003 FW190 Horizon
1973 Startcraft 18ft "Sea Pickle"

Just a follow up on this thread. I did look into my owners manual for our twin 5.7 GSI engines regarding what the specific language that was used for fuel recommendations. This is what my owners manual states. " USE ONLY UNLEADED FUEL. Maximum engine performance requires the use of lead-free gasoline with the following minimum or higher octane specification.

Inside the US.: (R+M)/2 (AKI) - 89
Outside the U.S.: (RON) - 93

If fuels with 89 AKI pump posted (93 Ron) octane number or higher are not available, lower octane fuels (minimum 87 AKI {90 RON} octane) can be used. With the use of lower octane fuel, a slight decrease in power can be expected."

So, I think I will continue to buy mid grade fuel where I can, but will run 87 octane when mid grade is not easily available.

_________________

Current Boat
- 2001 Four Winns 328 Vista "Hour Decision"
- 2010 310 Mercury Inflatable

Previous Boats
- 30' Doral Prestancia
- 25' Doral Citation

If the manual is telling you that; it suggests to me that the engine is equipped with a knock sensor that will momentarily retard the timing if knocking is detected. My 07 Jeep 5.7 Hemi has knock sensors and while 89 is recommended; you can use 87 without problems.
Now for engines that don't have a knock sensor I would advise using 93 when you can for the reason that engines octane requirements increase over time due to carbon build up and also it is hard to hear pinging and detonation in marine engines.

I always used 93 in my 88 because that's all the local gas docks sell. When I removed the heads to deal with the head gasket issue there was no sign of burning or detonation on the pistons.

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88 Four Winns 200 Horizon
4.3 OMC Cobra-4bbl
2002 Walker Bay 10/2012 Suzuki 2.5
2008 Walker Bay 8

1998 Jeep Grand Cherokee 4.0/Selectrac
2007 Jeep Grand Cherokee 5.7 Hemi/Quadradrive II

Ive used 87 exclusively since buying my Vista 278 in 2012. About 250 hours on 87 octane gas, and not one problem.

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1997 Four Winns Vista 278
T - 4.3l EFI
Kohler 4esz Genset
379 hours as of 8/8/21