'72' Johnson 25 SeaHorse

Captain TAJL

Recruit
Joined
Apr 24, 2002
Messages
2
Greetings Folks,<br />I have recently purchased 2 motors. This one listed and a '60' Johnson 18 SeaHorse w/ Elec. start and starter rope (which I hope to sell).<br /><br />I took out the 25 hp last Thu. and what a great running machine. 2 exceptions though, 1) while cold, the engine backfired in WOT and idle. The backfire in idle causes the engine to stall. After warming up, the higher rpm backfire subsided,<br />and 2) while cruising at high rpm the engine slips out of drive to neutral.<br />Any ideas?<br />Thanks in advance!!!
 

Franki

Lieutenant Junior Grade
Joined
Feb 16, 2002
Messages
1,059
Re: '72' Johnson 25 SeaHorse

Hi Capt TaJL<br /><br />Welcome to the list..<br /><br />I don't know your specific motor but I had a problem with my old OMC, where it would be crusing along at WOT and suddenly it would be screaming in neutral,,, and if I lowered the rpm right down, it would engage again..<br /><br />In my case, I had a selectric gearcase, and the forward clutch was worn.. I took it apart and swapped the forward and reverse gears around.. they were the same and it wasn't that difficult a job..<br /><br />However, that was an older motor then you have.. and a 72 probably had a hydro electric? (or maybe the smaller OMC's of that era had mechanical linkages??? I don't know... does it say selectric or hydro electric on the controller or anywhere else??)<br /><br />If its a hydro electric, then you have either a clogged oil pump in the gearcase or something weird happening with your electrics or soleniods..<br /><br />If I knew what type you had, I could probably make some better suggestions.. (then again, there are probably people on this list that will know the motor off the top of their heads..)<br /><br />as for your low rpm backfire.. you should clean the carbs.. check your plugs.. and get used to how the choke and stuff works on your motor.. these things never run perfectly smoothly at low rpm.. thats a trait of old carb two strokes.. but with judious use of your choke and stuff, you can minimise the problem.<br /><br />Also, if you just got this thing, have you checked the impeller??? <br /><br />you should get a manual, it will help you no end.<br /><br />regards<br /><br />Frank
 

Captain TAJL

Recruit
Joined
Apr 24, 2002
Messages
2
Re: '72' Johnson 25 SeaHorse

The seller told me the motor was tuned last year.<br />I did purchase a manual yesterday but will not see it until next week sometime.<br /><br />Thanks for the assistance. This motor is strictly a pull start. There is no battery needed.
 
D

DJ

Guest
Re: '72' Johnson 25 SeaHorse

Captain TAJL,<br /><br />The 25 John/Rudes are truly great engines, tough as nails. They are though a bit "cold blooded". They will sneeze a lot when cold.<br /><br />On you gear jumping issue, the cluth dog in the lower unit is shot.
 
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