1975 Johnson 135 HP not idling correctly

[kellandrick]

ok guys here we go. I have a 135 HP Johnson outboard that is giving me fits. The motor will not idle with out the warm start lever being up and then it only idles for a little while. Boat was used last season and then set up for a Texas winter (relatively mild winter) Motor had a new water pump installed last year. Just before I bought the boat the gentleman installed a carb kit and new plugs two of which I found to be fouled today after running boat once. the top plug on either side was fouled. Replaced NGK plugs with Champion UL77V plugs (all 4) This seamed to help combined with fresh fuel (50:1 87 octane) but still boat would not idle correctly. Even with the warm idle up only intermittently do you get the full idle RPM's. Takes some really tricky driving to engage drive and reduce warm idle lever to get boat moving but once moving she screams at WOT. Any suggestions on what I can do? (will be ordering a shop manual in the next week or two) I have looked at other posts and found a few ideas but guys i am a NOVICE when it comes to outboards. Any suggestions are GREATLY appreciated. Thanks and happy fishing!

 

[tashasdaddy]

Re: 1975 Johnson 135 HP not idling correctly

well it sounds like it needs some TLC, replace all fuel line with alcohol resistant lines. Carbs can get fouled at any time, get your manual, and Read carb cleaning, in TOP SECRET file, and do a link n sinc on the motor.

DO NOT buy a seloc, or Clymer manual, Buy the OEM Johnson manual.

 

[kellandrick]

Re: 1975 Johnson 135 HP not idling correctly

hahaha I am an idiot! tashasdaddy, i was looking over the motor this AM for obvious things. On the port side of the engine is a three position manual choke lever. all the way down is on and all the way up is automatic. I am assuming the middle stop is 1/2 choke, but anyhow the lever was shoved all the way down to the "ON" position. If my experiences with motorcycle engines is correct this would explain my performance problems with the boat not wanting to run at low idle unless the warm idle was shoved all the way forward and wanting to cut out and die when drive is engaged. Could this be my proverbial needle in a haystack?

 

[tashasdaddy]

Re: 1975 Johnson 135 HP not idling correctly

flooding it out. you probably found it. one position is off totally, one is so the choke button on control activates the solenoid, and works the choke linkage, the last postion is manual on. middle should the auto position, also you have a heat activated choke. there is a wire that needs to be disconnected. to stop the heat activation. let me find it.

 

[kellandrick]

Re: 1975 Johnson 135 HP not idling correctly

Thanks tashasdaddy now I cant wait to go back to the lake again to try it out and test the theory. To bad Texas is windy as anything today. Thanks for the help will let you know if this was the needed fix when I get a chance to try it out.

 

[F_R]

Re: 1975 Johnson 135 HP not idling correctly

Thanks tashasdaddy now I cant wait to go back to the lake again to try it out and test the theory. To bad Texas is windy as anything today. Thanks for the help will let you know if this was the needed fix when I get a chance to try it out.

Yes, try it and see if it is ok. The manual lever should stay in the auto position. The heat activated choke feature provides an automatic partial choke till the motor warms up enough to keep going without additional choking by the operator. Actually, it is a pretty good feature but sometimes overchokes under certain conditions. If that happens too often, it can be deactivated by a simple wiring change. For right now, I'd leave it alone. Who knows, it might already be deactivated?

 

[kellandrick]

Re: 1975 Johnson 135 HP not idling correctly

Well its official I think that was the idle problem. Went out yesterday and today on the lake once motor was allowed to warm up for a couple of minutes she ran like a champ and idles almost perfectly. And you lay into it from 1/2 throttle she goes nose up for a second then lays her head down and accelerates fast and smooth. GREAT RIDE for an old motor. Thanks for the help guys!!
HAPPY FISHING!

 

[tomil]

Re: 1975 Johnson 135 HP not idling correctly

well it sounds like it needs some TLC, replace all fuel line with alcohol resistant lines. Carbs can get fouled at any time, get your manual, and Read carb cleaning, in TOP SECRET file, and do a link n sinc on the motor.

DO NOT buy a seloc, or Clymer manual, Buy the OEM Johnson manual.

Hi tashasdaddy - any ideas from where can I get OEM manuals for Johson? Btw. why you do not recommend to buy i.e. Selocs? manuals?

 

[tashasdaddy]

Re: 1975 Johnson 135 HP not idling correctly

outboardbooks.com, searayman13 on ebay, then just ebay, johnson manuals.

I recommend OEM manuals, because they are correct. seloc and clymer are not complete, and have miss prints, and errors. most who buy aftermarket usually end up buying and OEM manual. do not get a CD, as they are hard to navigate.

simple solutions, can save big problems.

 

[tomil]

Re: 1975 Johnson 135 HP not idling correctly

outboardbooks.com, searayman13 on ebay, then just ebay, johnson manuals.

I recommend OEM manuals, because they are correct. seloc and clymer are not complete, and have miss prints, and errors. most who buy aftermarket usually end up buying and OEM manual. do not get a CD, as they are hard to navigate.

simple solutions, can save big problems.

Ok. Great! Thanks for your help. I'll try to find out OEM manual firstly. Then I'll clean my carb.