Cobaltchat.com

Group,
I am a new cobalt owner that purchased a 2014 200 with a new replacement Volvo Penta V8, 270 C-B engine

I have been a sailboat racer for 20 years and this is our first boat with more than a 20 HP engine and no sails. So we have a few Questions?

1.) After engine break-in (10-15 hours) what oil should we use? 10W-40 or 15W-50
2.) The 270 V8 has roller rockers so is synthetic oil best?
3.) What gas is best? 87, 90, 93?
4.) Ethanol or non-ethanol?
4.) Do most owners use a gas additive like Amzoil quick-shot or Lucas Fuel Treatment ?

Any help would be appreciated.

John

JB, welcome to the site and congrats on your new to you boat.
I will chime in on a few answers and defer to some to my learned colleagues here. First, if at all possible do not put ethanol fuel in that tank. You most likely will only buy a couple tanks of gas per year and the savings of buying cheaper ethanol gas is not worth the potential cost of dealing with water in the fuel and deteriorating rubber parts later. Most non-ethanol fuel in my area is 90 octane, seems to work fine. I would check the manual but for the cost of one oil change per year use the recommended lube, probably a 25w-40 like quicksilver, mercury, etc. or whatever VP says; it is basically a cast iron small block Chevrolet. Carburetor or injected? My old carbed mercruiser seemed to run better with an octane booster , my new fuel injected Volvo does fine with 90 rec fuel. Again welcome!

First. Change your impeller. Change your fuel filter, change your drive lube, change your oil Volvo Penta synthetic 10w40
Gas your engine is designed to run on 87 octane. You may have a issue getting non ethanol though. So go up octane rating till you get non ethanol.
I run a fuel additive first thing in the spring. Bg fuel additive. I use BG MOA oil additive in my engine and use BG synthetic gear lube for the drive. I use all Volvo penta filters for oil and fuel. I use a Volvo penta impeller. All easy to do it yourself projects. But you will need a special socket tool to remove the props to change the drive oil. You also need a new oring to replace on the drive oil drain plug and dipstick. Also only get Volvo penta orings. Watch you tube vids on them and protect the threads on the drive drain plug when installing the oring or you will cut it and lube the new one.

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Hey john. Welcome to the Cobaltchat forum. So glad you found us!

I’ve run both oil viscosity types in prior engines. Definitely run synthetic as the extra cost is worth the reduced wear particularly on start ups where much of the wear can occur and where synthetic clings to the cylinder walls better than conventional oil. I’ll check your VP manual for their recommendation but most likely 10W-40. If in warranty then use VP oil. We run 15w-50 Mobil One Synthetic in our Mercruiser with Merc filters.
Check out this oil thread too.

Yes, ethanol free if you can find it. 87-90 Octane will be fine. If you don’t plan on using her for a few weeks then add some type of stabilizer to the gas tank like Stabil, Sea Foam or PRI-G. If you can’t find E-free then add an ethanol treatment as well. We had issues with the lower octane ethanol fuel and had our gas tank pumped out due to phase separation of the fuel. It’s a real thing. Gas goes bad quickly if not used or treated. Read this gas thread here.

How about some pics...of both your Cobalt and your sailing machines.

Again welcome aboard mate!


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Welcome JB. You can go to pure-gas.org to find ethanol free gas. Just put in your zip. Sorry if this was already mentioned. As others said, ethanol in boats is not good.

Dub

Alaskabound wrote: Tue Jun 30, 2020 10:48 am Welcome JB. You can go to pure-gas.org to find ethanol free gas. Just put in your zip. Sorry if this was already mentioned. As others said, ethanol in boats is not good.

Dub

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Great point.
Love that App Dub.

Welcome from CA / AZ! Let's see some pictures.

Fantastic response! Thank you all!

Updates:
1.) Purchased Wix cartage oil filter 57186 (5 icnch) and 12 inch adjustable wrench to remove oil filter cap. (Easy)
2.) Purchased 6 quarts Amsoil 10W40 Marine synthetic engine oil. (Received great reviews and is Catalytic Converter compliant)
3.) Purchase DC oil extractor pump to remove the oil in the crank case -FAILURE! (Cheap china junk)

I am researching the West Marine manual oil changer #11047123 or the Jabsco Engine Oil Drain Pump to replace the failed dc pump.

Best regards,

John

Group,
Update two:
Unfortunately no fuel stations in counties east of me have non-ethanol fuel! So I drive 40 minutes with six 5 gallon gas cans or use an additive.

After significant research (talked to two motorsport race team owners, and the local NAPA owner and boater) I settled on using Amsoil gasoline stabilizer. One 16 oz. bottle mixes with 40 gallons of gas and keeps the ethanol from separating. Not inexpensive however hopefully a simple solution.

Best regards,
John

Yes blue marine stabile is good stuff too. Congrats. Do the impeller. you will thank me later.

Big Block,

I see you live near Neenah Wisconsin. I am due south of you near the Wisconsin border, about 15 mile east of Lake Geneva.
My Cobalt came from Gordy's located in Fontana on Lake Geneva.

We just installed a new engine. Question? Why would you suggest I rebuild the water pump impeller so soon? We only have less than 15 hours on the engine.

Sincerely,

John

Welcome. When did they replace it? How long has it been sitting. Every low hour boat this year on here that someone bought had the impeller go out. It's a bitch when it does. Just saying.

BBP,
Thank you for your concern. New "Crate Engine" installed in January, 2020, currently 15 hours of "break-in". Completing first oil change and filter today.
Regards,

John

JB Welch wrote: Fri Jul 03, 2020 7:39 am BBP,
Thank you for your concern. New "Crate Engine" installed in January, 2020, currently 15 hours of "break-in". Completing first oil change and filter today.
Regards,

John

Oh Good. Now get out and drive that thing like you stole it!!!
What size bb did they stuff on that 200 for you?

Just my 2 cents
I’m a firm believer in full synthetic oils
My machinists yelled at me when we put Mobile 1 in A new motor he put together after break in
He suggested we use a high zink oil for a while until the rings are fully seated.
Like 50 hrs of run time
Then go to the full synthetic, and yes the motor has a full roller vale train
Good luck and welcome to the club, great group of people