PDA

View Full Version : Prop relation to rudder



pmoomba
07-17-2011, 07:53 PM
We had a bit of an incident this weekend with a bent prop. Replacing it fixed the vibration and other issues we were seeing before replacing it so I think I'm good, but have that nagging sort of feeling.

If I get behind and underneath the boat, should the prop shaft/propeller be exactly in line with the rudder? Or is the rudder a little off center (to counter balance prop rotation I'd assume)? Looking behind, I see the shaft/prop more to the port side (left) than the rudder, but the shaft/strut don't appear to be bent.

jmb
07-17-2011, 08:47 PM
Yes, the prop shaft and the rudder are off set. You would be able to get the prop off this way and I believe it is also for steering.

outback98
07-17-2011, 09:04 PM
I did the same thing this weekend. Definitely bent the prop but also scratched the shaft. I don't think I bent it, should I replace it anyway or do you guys think it's ok?

jmb
07-17-2011, 10:18 PM
I guess I would replace the prop first, then take it out and see if I had any vibration. 50/50 chance I guess, but you might save from having to replace the shaft, imo.

DOCDRS
07-17-2011, 11:30 PM
the prop shaft is offset from the rudder so you can remove the shaft without removing the rudder

outback98
07-18-2011, 10:05 AM
Thanks for the advice. I was leaning that way, just needed another opinion.

Does anybody know how I can find out what prop I need? Thanks.

LakePerson1952
07-18-2011, 04:36 PM
I did the same thing this weekend. Definitely bent the prop but also scratched the shaft. I don't think I bent it, should I replace it anyway or do you guys think it's ok?

You can check the straightness of the shaft by mounting it to a lathe - you can also do it with a dial indicator (rotate the shaft while on the boat with the indicator firmly fixed to something) but that is probably not as accurate.

outback98
07-23-2011, 12:27 AM
Just ordered my acme 541. Nettles still gave me the discount. I'm gonna send my old prop back to them to get refinished for a spare. Hopefully I won't have to change the shaft and strut.