I have a 1999 270 searay sundancer, single engine with a Bravo 3 drive. The boat was repowered in 2005 with a 6.2 MPI. Original equipment was a 7.4.
I've owned the boat for a few years, and it has been great - however I've had one lingering problem (besides that damn cool fuel module!) .. My problem is with the WOT throttle range since I bought it years ago and I want to fix it before I burn the engine out.
When the boat was re-powered (by the PO) - the new engine was mated to the original bravo drive. The boat came with a bravo 3 from the factory with a 2.00 gear ratio with a 24 pitch prop set. (according to searay)
While the boat runs well enough (i cruise at 25-27 mph at 3400 rpm burning a little under 2mpg) - it tops out at about 4000 rpm - and it struggles to get out of the hole with heavy loads or later in the season with a season's full of marine growth added to the bottom. My concern is that eventually I'm going to damage the engine by operating it under too much load at lower rpms. Additionally, Ive met and read from a number of fellow 270 owners that their top speeds are much higher than mine, and that their cruise speed is closer to 30 and they are getting probably a little bit more than 2 mpg.
MY question is do you think I can fix this to some degree with different pitch props - or is it more of a gear issue in the drive and I'm stuck unless I invest a lot of money in the drive itself? It seems like I'd need to make an awfully drastic prop pitch change to accommodate 1000 rpm!
I called Mercruiser and they said the 6.2 MPI should really have a 2.2 primary gear in the Bravo 3 - as I mentioned earlier I am almost positive mine is a 2.0.
Do I try to go down to a 20 pitch set? (Thats the lowest I can go I believe) - or should I regear the drive. How much is something like that going to run?
Thanks for any input on this!
I've owned the boat for a few years, and it has been great - however I've had one lingering problem (besides that damn cool fuel module!) .. My problem is with the WOT throttle range since I bought it years ago and I want to fix it before I burn the engine out.
When the boat was re-powered (by the PO) - the new engine was mated to the original bravo drive. The boat came with a bravo 3 from the factory with a 2.00 gear ratio with a 24 pitch prop set. (according to searay)
While the boat runs well enough (i cruise at 25-27 mph at 3400 rpm burning a little under 2mpg) - it tops out at about 4000 rpm - and it struggles to get out of the hole with heavy loads or later in the season with a season's full of marine growth added to the bottom. My concern is that eventually I'm going to damage the engine by operating it under too much load at lower rpms. Additionally, Ive met and read from a number of fellow 270 owners that their top speeds are much higher than mine, and that their cruise speed is closer to 30 and they are getting probably a little bit more than 2 mpg.
MY question is do you think I can fix this to some degree with different pitch props - or is it more of a gear issue in the drive and I'm stuck unless I invest a lot of money in the drive itself? It seems like I'd need to make an awfully drastic prop pitch change to accommodate 1000 rpm!
I called Mercruiser and they said the 6.2 MPI should really have a 2.2 primary gear in the Bravo 3 - as I mentioned earlier I am almost positive mine is a 2.0.
Do I try to go down to a 20 pitch set? (Thats the lowest I can go I believe) - or should I regear the drive. How much is something like that going to run?
Thanks for any input on this!