duckhunter55
Petty Officer 3rd Class
- Joined
- Oct 13, 2007
- Messages
- 94
ALright finally got the old motor out of the garage again to try and get running right once and for all. Its a 1978 25hp Johnson. A little background info. Originally a manual start, but i have added a 1978 25hp electric starter on to it. I also have replaced the pull starter housing with an older 25hp housing. The reason being, one day while riding down the river i hear a rattling coming form under the cover. stop motor and take off cover and notice that the screw that holds the pull start assembly together had com out and allowed the spring inside to come out and somehow made the whole top of the pull assembly crack. The motor started and ran flawless before this, but after trying to repair the hosing with epoxy and stuff, for some reason the motor will now backfire and pop very loudly upon trying to start but will start after several hard pulls. It will then run, but very eradically and only if i mess with the choke and throttle, but it will eventually die. Then it will NOT start up again after it cuts off that first time until usually the next day. YOu can pull and pull but it will not start, it just continues to backfire and pop. After about a day i can go out and do the same thing. I have tried everything, cleaned carbs. set throttle cam, etc... And I believe i have narrowed down to the timing being 180' off. Now that you have all the background info , I am not 100% sure how to set the timing. I have the johnson manual and i just bought a timing light. Several Q's
1)Does the motor have to be at wide open throttle to set the timing?
2) Do you have to do this at night, cause im holding the timing light on the flywheel with it running but its not doing anything. Shouldn't it freeze the marls in place?
3)Could there be a pre set position that i could turn the screw to, to maybe get it close to the right timing so at least it will start. ie. halfway screwd or 3/4 ways in.
4) Lastly which way do i turn the screw to advance or retard timing?
Sorry about the long post but Im finally ready to get this motor running once and for all! thanks Luke
1)Does the motor have to be at wide open throttle to set the timing?
2) Do you have to do this at night, cause im holding the timing light on the flywheel with it running but its not doing anything. Shouldn't it freeze the marls in place?
3)Could there be a pre set position that i could turn the screw to, to maybe get it close to the right timing so at least it will start. ie. halfway screwd or 3/4 ways in.
4) Lastly which way do i turn the screw to advance or retard timing?
Sorry about the long post but Im finally ready to get this motor running once and for all! thanks Luke
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