evinrude gearbox 25hp

[golly]

hi guys can any one tell me if a 1984 [h=1]evinrude gearbox 25hp[/h] will fit my evinrude 1974 engine, as when im out in the boat i put the power on slowly, it pulls good but when it gets to half throttle the revs go right up as if its come out of gear and screams , any help with this, ive seen this 1984 box for sale but dont know if it will fit

 

[hardwater fisherman]

Have you checked the prop to see if it is spun on the hub?

 

[Tim Frank]

^^^ +1 .....get your prop repaired if there is a shop nearby that can do it....or buy one from iBoats.

 

[golly]

i have put a new prop and pin on and its the same

 

[golly]

i was told it can be the dogclutch thats why i was asking about the 1984 box if its the same ill buy it and put that one on. [h=1][/h]

 

[milliesdad]

Does it feel like you hit a submerged object when this happens?

 

[milliesdad]

Have you taken apart and checked the lower unit gears? If not, you are throwing money at it and hoping that this will fix it.
How do you know that the parts are interchangeable?


Check a parts diagram for both years and see if the parts are the same.

 

[golly]

no i have not taken it apart yet , i have just got the engine off ebay where the guy said it all run good but needs a new prop.

 

[Tim Frank]

Do a search in Forum of "worn clutch dog" ~ AND ~ "spun prop hub" and see which condition matches your symptoms.

 

[F_R]

hi guys can any one tell me if a 1984 [h=1]evinrude gearbox 25hp[/h] will fit my evinrude 1974 engine, as when im out in the boat i put the power on slowly, it pulls good but when it gets to half throttle the revs go right up as if its come out of gear and screams , any help with this, ive seen this 1984 box for sale but dont know if it will fit

That describes either a prop hub or the motor is coming out of the water. If it were a gears problem, it would actually come out of gear, OR make an awful grinding /banging noise. You wouldn't by any chance be running a short shaft motor on a long shaft boat, would you?

 

[golly]

its a long shaft motor . i have now tryed it in a water tank and its the same thing, low revs ok high rev sounds like a motor thats come out of gear but the arm has not moved. it is the right prop is it 9x10 no grinding /banging noise.

 

[racerone]

You may find that the driveshaft has a different spline on the 2 models in question.

 

[golly]

its an old motor its pin drive no splines

 

[F_R]

So, you say you put on a new prop. Are you saying a brand new, never used one? Anyhow, props can be tested. Make a mark on the prop nut and another on the prop, aligned with the first one. Then run it till slipping occurs. Stop motor and check your marks. If they are no longer aligned, the hub slipped. Testing is better than guessing.

 

[racerone]

Again folks mis-understand.---The splines on the top of the driveshaft may be different between an 84 model and a 1974 model !!

 

[golly]

So, you say you put on a new prop. Are you saying a brand new, never used one? Anyhow, props can be tested. Make a mark on the prop nut and another on the prop, aligned with the first one. Then run it till slipping occurs. Stop motor and check your marks. If they are no longer aligned, the hub slipped. Testing is better than guessing.

ok i give it a go thanks.

 

[golly]

Again folks mis-understand.---The splines on the top of the driveshaft may be different between an 84 model and a 1974 model !!

yes i did , ill have look many thanks guys .sorry to be a pain but im new toto all this.