prop or coupler

[ringmaster]

i have a 1977 sea ray with a 233 mercruiser and pre alpha outdrive. yesterday i took the boat for one last ride. it was a 3 our ride total on the way back i was cruising at 3200 rpms roughly 30mph. all of a sudden my rpm's jumped to 4000. i quickly idled down and trimmed the outdrive all the way down. my boat never stoped moving so i took it slow at taking off agian. the boat got right up out of the water and ran great but as soon as i would try to trim it out agian the rpm's would rise but as long as i kept the outdrive trimmed all the way down it would run fine. could the coupler or the prop be slipping?

 

[Don S]

Re: prop or coupler

Impossible to tell without checking. Mark the prop and hub and try it again. See if the marks are still aligned. Sounds more like something on the prop (line, plastic bag, bent blades etc.) more than being spun or the coupler spun.

 

[chiefalen]

Re: prop or coupler

Did it over heat?

 

[ringmaster]

Re: prop or coupler

there was nothing on the prop at all and no it never got hot att all. when i noticed it trimed down after a few minutes i tryed to trim it out and as soon as i touched the button the motor would rev up. i know its time to replace prop cause it been through alot. im not to concern with it since summer is over and im putting it away next weekend i just thought i would ask to get some opinions. what would cause cavitation? thanks.

 

[chiefalen]

Re: prop or coupler

Was it rough, high seas? Where you pounding thru the waves?

Was the back of the boat, prop coming out of the water.

Could be a spun prop.

Do you have a spare?

I always have a spare onboard, and so should you.

Coupler goes you overheat cause the water pump in the drive is disconnected.

So not the coupler. If it kept slipping out of gear different story than clutch dog.

But you trimmed down you said and problem went away.

Thats why i ask was it rough seas or you were going to fast in sea condition, maybe you should have been going 20 mph.

 

[jaxnjil]

Re: prop or coupler

don had the best idea
sounds like what happened to us last year in our bayliner with the I 165. and it was a spun prop

 

[ringmaster]

Re: prop or coupler

thats what im thinking cause the water was smooth as glass. i have a few other props i just might try one bofore i put it away.

 

[ringmaster]

Re: prop or coupler

i just took the prop off and its pretty obvious its the prop there is alot of burnt rubber on the inside of the hub. time to get a new one.