I need to pop in a new impeller on a 1978 25hp Johnson Seahorse, I have done an impeller on a 4hp Johnson and found it straight forward enough but I’m a little worried about tackling the bigger engine in case theres more to it than meets the eye,
Can anyone tell me if there is some sort of linkage that I need to disconnect before I try to pop off the bottom section,
Or is there any tricks or nacks in putting it all back together, I do know there are 2 different types of impeller for this engine and will be checking that out when I get a chance to get down the coast to work on it, while I’m at it is there anything I can wash out any salts that have built up over time, I may as well do that while I’m there,
Again in anticipation of your kind help I thank you,
Mike
1978 Johnson 25hp Impeller replacement advice
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Re: 1978 Johnson 25hp Impeller replacement advice
There is probably a linkage that you will need to undo to get the bottom unit off.
My advice would be to download a manual from this site. I cently did and its really good value and works well and quickly.
http://readmanuals.com/outboard.motors/
they have manuals for that age johnson
My advice would be to download a manual from this site. I cently did and its really good value and works well and quickly.
http://readmanuals.com/outboard.motors/
they have manuals for that age johnson
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Re: 1978 Johnson 25hp Impeller replacement advice
Thanks for this link Adam,
its a handy one to have and cheaper than I could find anywhere, I came back on here a week or so ago to delete the post - I’m glad I never now - this link will save me time in the future,
After I put the post up I went to “yahoo answers” and asked on there, 2 people came back with the info I was looking for,
There is a plate half way up the leg and they say behind this is the linkage I needed to know about
Thanks for taking the time Adam,
Cheers
Mike
PS, Bet that pike would give your tope a run for its money
What weight was in the pike, i'm thinking around 25lb, more maybe ?
its a handy one to have and cheaper than I could find anywhere, I came back on here a week or so ago to delete the post - I’m glad I never now - this link will save me time in the future,
After I put the post up I went to “yahoo answers” and asked on there, 2 people came back with the info I was looking for,
There is a plate half way up the leg and they say behind this is the linkage I needed to know about

Thanks for taking the time Adam,
Cheers
Mike
PS, Bet that pike would give your tope a run for its money

What weight was in the pike, i'm thinking around 25lb, more maybe ?
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Re: 1978 Johnson 25hp Impeller replacement advice
Hi Mike
Yeah its a handy site alright. The PDFs are actually decent quality and they seem to have mose engines covered even ones with out of print manuals. I recently got one for a 1989 merc and a late 90s suzuki which i was finding difficult to get elsewhere.
You might try to look on i-boats as well for some info there are some knowledgable people on there. Its worth it just to be sure there are no particular quirks for your engine. On an old one that we changed the impellor on you had to be very careful with the clutch rod and there was a small ball bearing that can get knocked out of place which jams the gear change. Found out about it on i boats and was able to avoid it.
Good guess the pike was 26.6
Yeah its a handy site alright. The PDFs are actually decent quality and they seem to have mose engines covered even ones with out of print manuals. I recently got one for a 1989 merc and a late 90s suzuki which i was finding difficult to get elsewhere.
You might try to look on i-boats as well for some info there are some knowledgable people on there. Its worth it just to be sure there are no particular quirks for your engine. On an old one that we changed the impellor on you had to be very careful with the clutch rod and there was a small ball bearing that can get knocked out of place which jams the gear change. Found out about it on i boats and was able to avoid it.
Good guess the pike was 26.6

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Re: 1978 Johnson 25hp Impeller replacement advice
Adam S wrote:Hi Mike
You might try to look on i-boats as well for some info there are some knowledgable people on there. Its worth it just to be sure there are no particular quirks for your engine.
Thats not a bad idea, I did try to join that site a couple of months ago but had problems,
It may be because I might have signed up to it in the past and used the same address, I will give it another go during the week,
Good guess the pike was 26.6




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Re: 1978 Johnson 25hp Impeller replacement advice
i have a copy of that manual, if you want pm me your address and i'll put it on a disc for you and post it to you.
niall_b73
niall_b73
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Re: 1978 Johnson 25hp Impeller replacement advice
Niall
So sorry about the delay in getting back to you "PM" sent
PS, Forgot to add that the impeller is sorted now so thanks again lads
So sorry about the delay in getting back to you "PM" sent

PS, Forgot to add that the impeller is sorted now so thanks again lads
