how to use high/low speed knobs

[wes_moore]

Hey guys <br /><br />Its me again I all ready wrote to you "info about my johnson 1.5hp". in it you said some thing about high and low speed knobs and adjusting them.<br />But I haven't got a clue how to know when they are and aren't right. Also you said that the fuel ratio was 50:1 but seeing as it is so old would it not need more oil I was talking to a mechanic who has alot of experience with johnson and said that it does change with age. Is this true? also since the spark plugs have changed code, do you know the know the new equivilant for them. I bought a new one but it is not as powerful or something but it just doesn't sound or feel as good.<br /><br />Thanks yet again <br /><br />Wes

 

[tmcalavy]

Re: how to use high/low speed knobs

Hey Wes,<br />Older outboards, those old enough to have bushings instead of bearings, say from 63 back, need more oil...generally 16:1 or 24:1. Yours is modern enough to have bearings, so 50:1 is correct. Adjust high and low speed knobs this way. Get it running on the boat and bring it up to speed (fast). Turn the high speed adjusting knob slowly until it starts running rough, then back to the place it was running good. You may have to go Clockwise and counterclockwise with the knob to find the "spot" where it runs best. Now idle it down (slow) and repeat the process with the slow speed knob...turn it slowly until you notice a miss...then find the spot again. That's all there is too it, except you may have to repeat the process as the season's change...may run different in winter than summer, etc. Have fun and find a manual for your engine/motor.

 

[tmcalavy]

Re: how to use high/low speed knobs

Make sure your plug is gapped correctly...I'm guessing its about .030 without even knowing which plug your running but that's a good standard for most rudes and j-sons. If you can't find the plug you want locally, check ebay motors under parts/accessories, then boats/motors. Always a good supply of well-priced plugs there.

 

[wes_moore]

Re: how to use high/low speed knobs

Hi<br /><br />just to say thanks Tim Mc.I think its really helpful to get all of this help and everything. which is always right and give brilliant tips.<br /><br />thank you <br /><br />p.s. I'll probably think of another question so see you all again later.

 

[Yepblaze]

Re: how to use high/low speed knobs

Try a Google search on adjusting carbs

 

[Scoop]

Re: how to use high/low speed knobs

Tim, has it right on the adjusting of the carbs. He said exactly what my manual said and I do. He is also correct on the oil mix although there are a lot of differing opinions. <br /><br />Definitely before '63, use 24:1 with a good TCW-3 oil. I have never seen someone disagree with 24:1. You may have to change plugs more often and decarb more often, but it will lubricate your engine better. <br /><br />As far as using greater more oil in a post '63, I have not run enough motors to know. The idea makes sense, but does it help in the real world?

 

[CalicoKid]

Re: how to use high/low speed knobs

I have been warned of running a motor too lean (fuel/air) and burning it up when adjusting mixture knobs on little old outboards. I've never done any harm this way though, just a thought.

 

[Scoop]

Re: how to use high/low speed knobs

I have heard that to Calicokid, When I adjust the low speed, I get it where it is running good, then go to a little to the richer side. Not enough to make it run rough, but enough to be safe. Don't know if it will help prevent a lean condition or if it just makes me feel better without helping.