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mainliner61
11-08-2009, 09:31 PM
"I have a 225 vmax Series 2. It run smooth at any rpm exept wide open then it surges and won't get over 5700.Sometimes it runs great and allows 6000 rpm. Rev limiter is 6200.Seems like it does worse when I hold it under 5000 for very long before I open up.This morning it ran great,74gps,this afternoon it started that crap when I needed it most and could only get 68. Any ideas?"

outboard_doctor
11-09-2009, 04:30 AM
"Look for any fuel restriction, i would put a vacume gauge in the fuel line (between engine and tank) and check what vacume you have"

justintime
11-10-2009, 04:31 AM
sounds like fuel pumps or spark plugs

mainliner61
11-13-2009, 08:40 PM
Thanks for the info. I noticed today when I put gas in it that one tank held 4 more gallons than the other.They are suppose to drain equally.Bet it is a restiction.Plugs are new but that is still possible. I'll check them first

mainliner61
12-05-2009, 10:28 PM
My Yamaha Vmax is turning 6100rpm in the cooler water temps with a 25p Yamaha t1 prop.If I put a 26p on it would it give me more speed or just drop rpm's?

outboard_doctor
12-06-2009, 09:08 PM
You will lose alittle on accelleration but gain some on top end speed

mainliner61
12-27-2009, 07:14 PM
Thanks Jamie and just-in-time for all the help. This is my first Yamaha.I've had 2 Mercurys and so far the yami is much better.The surging problem must have been a restriction that it passed on its own.It finally stopped and hasn't done it since. Thanks again!

justintime
12-29-2009, 03:05 PM
6100 is a little too much

run the 26

mainliner61
12-29-2009, 08:29 PM
Yamaha dont make a 26p but a 27p they do. I think the 27 would kill my hole shot. Would a Tempest 26 or Fury 26 be good? What prop do You suggest? Thanks