Cobaltchat.com

Bleil05 wrote: Fri Jul 03, 2020 4:47 pm 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

Yes he is correct. Zinc in oil is getting very hard to get. The engines we get now are pretty much all broken in and come prefilled with syn oil. Engines use oil now because they use low friction rings and they get stuck in there groves from carbon build up. Direct injection doesn't help any of this either. That's just the tip of issues going on. But yes run syn in a Volvo and I think merc is a blended oil.

Bleil05,

That is exactly what I wanted to do. That is my standard procedure for my many race engines!

However, After talking with multiple experienced wrenches and engine builders they were worried the zinc would harm the catalytic converter which would upset the ECU and the engine would drop to limp mode. Big problem, big expense. So I ended up with the Amsoil 10W40.

At the end of the season, before I store the boat I hope to complete a leak-down test.

Happy Independence day !!!

JB Welch wrote: Mon Jun 29, 2020 10:55 pm 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

I'm a bit late to this thread, but I'll add my two cents anyway. For oil, I like Mobil 1 15w-50. Cheap at Walmart, and has higher ZDDP than most synthetics and is a bit thicker for the relatively high constant loads that marine engines face.

As for gas, the boat will run fine on 87 octane, but your Volvo can advance the timing a bit and make use of 89 octane if available (very slight boost in power). Definitely non-ethanol if you can find it, but it can be hard to find. Usually marked for "offroad use only" or some such thing around here - I've used https://www.pure-gas.org to find a source many times.

The fuel treatments you list aren't as beneficial as Stabil Marine, which has additive specific to the marine environment and they even have an ethanol version too See for example.

An impeller in a new engine SHOULD be fine for a few years, but it's a common wear item people forget about and causes headaches once the little fins start breaking off. Make a note to grab one in a few summers.

John