Cobaltchat.com

Hi All,

After doing my homework over the past several years, and also following this forum, we ended up making the call to purchase a Cobalt. Our requirements centered around an all around family friendly boat that has some class, performance, comfort and long term quality. We were lucky to pick up a very well kept 2006 220 earlier this year and after driving it and seeing the quality and details up close, we now see why all of you are so enamored with Cobalt Boats. I know, now the big question is, what does it have under the hatch? Thankfully it had the 8.1 GX-I with the DPS-A so it has some giddy-up at all throttle positions.

My question revolves around the duo-prop propellers, but not for the usual reasons. Currently have the F7 setup and the boat is plenty quick off the line and the top end is 60+ - Check and Check. My issue us I dinged a single blade on the front prop and sent it out for repair. Because of the bend angle, they are going to try and repair but I am stuck at the dock. Would be a good idea to have a spare, but they are out of stock pretty much everywhere. From following this site, I know that there are a lot of resources to tap into.

Are there any aftermarket prop setups that can be used? My first VP with only working knowledge about outboards which have lots of prop options.

A F6 setup is an option but then I need to get the whole set, not just a new front.

I look forward to the feedback and also being able to help assist others down the line. I have always tried to handle maintenance and repairs on a wide range of motorized vehicles when possible.

Thanks

Good luck... a lot of us are waiting for our VP props from the factory. I have a spare set for my R8S I've had it for a year and a half only to find out it was the wrong pitch for my boat. So I'm waiting on two sets of props, I've been told I'll get them when I get them. Some of the other guys that have been around longer than I have may have some better news for you or at least something you can use so you don't waste the rest of the season.

I think you are at the mercy of the prop guy. 2 weeks is typically the going wait for a repair this time of year. You would be amazed at the work some of these guys can do and most will have it balanced and sharpened. I think you will need to stick with the F7 if it is hitting your RPM's. I would not recommend going to a different pitch set for the sake of having a back up.

Congrats on that boat. Surprised it has f7 props on it. Depending what gear ratio you have 1.92?
Don't go with with aftermarket props. Hill marine makes them and they are junk.
What WOT rpm are you getting?
I have F6 on mine. That's what I would think you should need. But hey if your getting 60 plus and a great hole shot congrats. It's that GPS speed?

The gear is 1.78. I havent had a chance to do the GPS speed track yet but was planning to this weekend before the prop issue.

BBP, does the F6 give a better hole shot? Mid-range punch? And these days, mileage?

Canterbury wrote: Wed Jul 27, 2022 9:44 am BBP, does the F6 give a better hole shot? Mid-range punch? And these days, mileage?

So the 8.1gi uses a F8 prop and the 8.1gxi uses the F6 and a 1.78 ratio with both engines.
Yes the F6 will have a better hole shot and midrange punch and a lower top end speed. Your rpms will be between 200 to 400 rpms more also.
I hit 5000 rpms at WOT. worse mpg.
https://www.boat-fuel-economy.com/volvo ... us-gallons