Won't go in reverse-just grinds

[AJT]

I have a '86 Yamaha V6 150hp. Last year ran well. Went out this spring and after the 2nd day it would not let me get it into reverse (occasionally it would). It would just grind. Brought it home and put the hose and muffs on it- no problems. Took it back to the lake and started grinding again when attempting to put it in reverse. When I go forward for a few minutes it will let me put it in reverse a couple times, then it starts the grinding again. Took the 703 control unit apart and everything seems to look ok. Greased and sprayed lub on the cables and the connections look good. I took it to the lake tonight and when I have the hood off and help it go in reverse (at the engine) it will go in. Any thoughts for my next step.

 

[rodbolt]

Re: Won't go in reverse-just grinds

hello<br /> that is all the signs of a shift shaft that is almost rusted in two. look at the shaft where it enters the gearcase. its a small gap at the swivel tube. the 86 yammi had a plain steel shaft and they did rust away. the problem was at the very end the shft would twist instead of engauging the gears causing trashed lower units as well. fix it and quit the grinding. or you could have a shift cable that is splitting open. my bet will be on the shift shaft.<br /> good luck and keep posting

 

[AJT]

Re: Won't go in reverse-just grinds

Thank you for the reply. The cables are in pretty good shape- don't see any exterior damage. Looking through the cracks and crevises I see a shaft that is about 3/8" in diamiter, is this the shift shaft? From what I have read on other posts this is what I came up with. A SS replacement shaft is available for about $35-40, I must take the powerhead off, the bolts could be very hard to remove, should take 1-2 hrs, and then I will need a powerhead gasket. Is the powerhead and lower unit the same? If I bought the Seloc repair manual for this motor will that be enough of a resource to walk me through it, or would it be better to take it to a shop? Any other maintenence I should do while it is apart?<br />thanks again,<br />Allen

 

[rodbolt]

Re: Won't go in reverse-just grinds

hello<br /> has this motor been in salt water?<br /> the shift shaft is about 1/4 in diameter.<br /> usually you can see the rust on it. an easy test is to remove the lower unit and see if you can twist the shaft with vise-grips.<br /> if the motor spent much time in the brine they can be terrible. 2 hours to replace the shift shaft is a pipe dream. aint gonna happen.<br />if you dont know the difference between the lower unit and the power head a seloc or clymer aint gonna help. if I were you I would work some overtime and have a pro do it.<br /> but if ya decide to do it yourself odds are we can be of some assistance.<br /> good luck and keep posting

 

[AJT]

Re: Won't go in reverse-just grinds

Thanks rodbolt for the info and please keeep it coming.<br />Does the power head or the lower unit have to be removed to replace the shift shaft?<br />I've had the boat for only a year so I'm not sure if it has been in salt water, I don't think so. Also I have not idea what has been replaced on it.<br />I haven't had any problem shifting it into forward yet. I took a screw driver and scraped some grease off of the shift shaft and I see the light blue paint and when I scrape harder I see no pitting or rust just shiney metal. Does the rusting occur in a different spot? When I turn the prop by hand with it in neutral I hear and feel a clicking every eighth turn or so. Not sure if all this means anymore.<br />Allen

 

[AJT]

Re: Won't go in reverse-just grinds

If this still sounds like the route I should take would it be wise to replace the impeller at the same time? I'm not experiencing any problemns in that department.<br />Allen

 

[AJT]

Re: Won't go in reverse-just grinds

I adjusted the cable connector out about 3/8" back at the motor, took it to the lake and seems to have done the trick. <br />thanks for the advice<br />Allen