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1978 25hp evinrude forward gear tries to jumps out

M

motiondave

Contributing Member
Hello people, Ive been watching youtube videos and reading as much as I can
I have the motor on forward controls, in this case, two levers, one for gear, one for throttle.
my 25hp evinrude tries to jump out of forward gear at higher rpm, its like a sledgehammer bashing the back when it does.
at this stage, to overcome it, Ive been holding the gear lever at the front a bit more to hold it in gear.
im still adjusting the cable to hold it, but it still seems like it wants to jump out of gear.
and yes , Ive tried it with cable disconnected and it does the same thing.

Ive replaced the spring at the top of the motor which helped a lot, but could not find a factory replacement, so I found something from a hardware store.
so unless a stiffer spring might help
I did read that the dog clutch teeth could be chewed enough.
however, I am looking and have not found, if there is an adjustment that can be done, be it at the top of the engine or in the gearbox, that might overcome this.
sometimes a loose bolt or adjustment fixes a lot.
I have been doing reading and hopefully, someone can please point me towards a check list of adjustments for me to look at first, before I start pulling a gearbox apart.

can anyone assist please.
Kindest Regards, David Lane.
 
After all this fiddling / makeshift repair attempt it is too late.-----Lower unit has to come apart.----Used gears may be found on ---E-bay for example.
 
It sounds like a worn/damaged clutch dog , and maybe forward gear

Once the "dogs" get the corners chewed off their ears they easily slip out of engagement under load. Often caused by engaging gear gently instead of a quick snap action.

But if the lower unit has recently been removed , eg for a pump overhaul, check that the upper and lower shift rods are correctly located in the linking clamp before tearing into the gear case

See this recent thread which discusses the issue of this clamp and also mentions an adjustment to the positioning of the shift lever

http://www.marineengine.com/boat-forum/showthread.php?464128-Replaced-gears-Still-slipping


Beware o fthe mountain of misinformation that you will find in youtube videos. If you have any problems ask on this forum ( or another well known one where many of the same people will respond)
 
Thanks Vics for the reply, it was slipping gears (only in forward) when I got it, the spring on the top was replaced and that helped a bit, but it still wants to boot out of gear. I actually removed the bottom unit today , so thats interesting about upper and lower gears shift rods as when I went to put it back together, the damn rod would not connect properly, so I will remove it tomorrow and check again. including the connector as described in the other thread.
also, Im trying to find the adjuster on or as part of the shift handle at the top. Not sure what im supposed to be looking for
I see, for the diagram #38 and #39 indicate adjustment, I will have a look at that, is that what Im supposed to be looking for?
thanks for the help so far.
Dave.
 
Hi people, just to let those whom advised, and I greatly appreciate the help, I gave up on the 25hp, it needs a new prop, rebuilt starter and some other parts for the gear linkage.
once this little boat is all sorted, I will look at a larger motor later, like a year or two.
short story long, I swapped it with some extra money onto for a short shaft 15 HP Johnson, which should be sufficient enough to move the little boat its planned for.
So thanks for the help people, I have started a new thread for the wiring help for the 15 HP motor
 
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