78 25horse outboard that jumps out of forward gear

GoBlue

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Jun 23, 2009
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i have just bought a 25 horse elec start evenrude that has had a lower unit transplant by the previous owner. it has suddenly begun to jump out of gear when doing anything more than idleing in forward.i am a novice when it comes to outboards but have done some work on it and can find my way around ok. i have also noticed you have to work at it to get it in forward, realy push it forward all the way and finaly it engages only to jump out while coming up on plane. i have seen some things in forums that suggest a linkage adjustment issue, or clutch dogs. any info would be great and might help put my daughter and i on the water soon!
 

lindy46

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Re: 78 25horse outboard that jumps out of forward gear

Sounds like a bad clutch dog/forward gear. You say the previous owner replaced the lower unit? I assume he put another used L/U on? Is it a manual shift or electric shift?
 

GoBlue

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Re: 78 25hp outboard that jumps out of forward gear

Re: 78 25hp outboard that jumps out of forward gear

it is a manual shift. took the lower apart and the dogs look ok. one lug has a slightly rounded edge but im not real sure what im looking at. actually took it off and cleaned it up. seems pretty straight forward. can i simply buy a new dog and switch it out? no chance it's a linkage issue? Also, it doesn't really jump when it slips out, it just redlines untill i throttle down
 

lindy46

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Re: 78 25horse outboard that jumps out of forward gear

Those edges get rounded on both the clutch dog and forward gear. You must replace both so they mesh properly. That forward gear is really expensive new. I'd start looking for another (good) used lower unit. You could check the linkage - disconnect shift cable and shift it manually. Make sure it's going all the way forward. Are the ends of the shift rods properly fitted into the coupler with the bolts tight and engaged in the recess in the shift rod ends?
 

GoBlue

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Re: 78 25horse outboard that jumps out of forward gear

Those edges get rounded on both the clutch dog and forward gear. You must replace both so they mesh properly. That forward gear is really expensive new. I'd start looking for another (good) used lower unit. You could check the linkage - disconnect shift cable and shift it manually. Make sure it's going all the way forward. Are the ends of the shift rods properly fitted into the coupler with the bolts tight and engaged in the recess in the shift rod ends?


do you know where i could find a decent lower, and any idea how much.i see some scoring and it would probably be a good idea to change the entire thing while i've got it opened up. I hope its not to expensive, i have a very stressed income right now
 

jasper60103

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Sep 18, 2008
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Re: 78 25horse outboard that jumps out of forward gear

twincities outboard will likely have it and it comes with a 30 day warranty. The problem is it will cost you around $600.
So buying a manual and scavenging ebay for parts sounds like a pretty good alternative. Just my 2 cents.
 

jbjennings

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Jul 18, 2007
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Re: 78 25horse outboard that jumps out of forward gear

I personally think you have a combination problem of a bad shifter adjustment, or a bent linkage in the lower unit. The clutch dog and forward gear can't really have any rounding off at all without slipping at wide open throttle. I believe if you got the shifter adjusted properly, it'd still probably slilp during WOT. I'd try ebay, laingsoutboards.com, aomci.org (free classifieds) for a used lower unit or possible new clutch dog if the forward gear isn't too bad, but you'll need an expert to determine what "not too bad" is.
JBJ
 

GoBlue

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Re: 78 25horse outboard that jumps out of forward gear

I personally think you have a combination problem of a bad shifter adjustment, or a bent linkage in the lower unit. The clutch dog and forward gear, can't really have any rounding off at all without slipping at wide open throttle. I believe if you got the shifter adjusted properly, it'd still probably slilp during WOT. I'd try ebay, laingsoutboards.com, aomci.org (free classifieds) for a used lower unit or possible new clutch dog if the forward gear isn't too bad, but you'll need an expert to determine what "not too bad" is.
JBJ

thanks for the info. is changing the clutch dog as easy as sliding it off,and putting the new one on? I plan on getting a manual, also it slips at any throttle except slightly over idle. I think you are onto somthing with the bent linkage b/c the forward gear seams to have all but disappeared. i have to push the gear shift all the way forward and then at the very end i feel it engage. yet the others engage fine and solidly. thanx
 

lindy46

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Nov 27, 2008
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Re: 78 25horse outboard that jumps out of forward gear

do you know where i could find a decent lower, and any idea how much.i see some scoring and it would probably be a good idea to change the entire thing while i've got it opened up. I hope its not to expensive, i have a very stressed income right now

Check Ebay or go to AOMCI and place a want ad here:
http://www.aomci.org/cgi-bin/yabb2/YaBB.pl?board=Webvertize
 
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