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60HP Johnson 1970 ESLD Erractic Idle

4

48tony

Regular Contributor
I got my boat out of the shop about a month ago after replacing the whole ignition system. Also replaced with new parts, few pump, new gas tank and line and rebuilt carbs. Put dual stage Boyson reads on it. Ran real well when got out of the shop. I tried to lower the RPM's so I could do some trolling. By doing so, I dropped the RPM's and fiddle with the carb low-speed needle valve. Since then, I have had problems with hard starting and exceleration. Manual says to set needle valves 3/4 and start with the middle until I get the sweet spot. Still won't idle correctly. I almost think it is flooding itself out. When I do finally get it to run at half throttle she'll run real nice. Then drop it down to slow she will start to run rough. And sometimes she'll stall out. Then I go to start it and it seems I have to use the cold start/high level lever to get her to kick. And even then sometimes it won't start. If I let her sit for a few minutes then she'll start only with assistance of high idle lever. Joe Reeves gave me some feedback on the carb adjustments. Set RPM's as low as possible, starting with mid-carb, turn in 8th inch turns until highest RPM is reached. Then turn RPM's back down. Tried this but no luck.

In between carb settings do I need to drop RPM's or is it just the initial adjustment on the mid-carb? Either way, she won't run right. By me turning the idle speed needle out beyond the 3/4 or 1 1/2 turns it seems to want to run a little better, but again at start up it does not want to kick unless I wait for awhile. Also, the RPM's seem to fluctuate say I get her up and running with idle RPM's at approximately 650-700, do a few laps around the pond, drop her back in neutral, RPM's drop down to 300-400 and almost dies on me. And at times it will die. It seems it definately a carb problem. After dealing with this I took the carbs off for the hundreth time, took Welch plugs out, used carb cleaner and air and fine wire, adjusted floats, put muffs on it outside, got it to run great again. Went to the lake back to the same problem. Can someone please help me?

Thanks,



Tony
 
All idle adjustments, both mix and rpm must be done with boat in the water.
This to get the correct back-pressure in the exhaust system.
The idle rpm MUST be set with engine 'in gear' forward, and boat not tied, about 750 RPM.
If you try to go below that, engine will be unstable and probably die out on you after a short while.
If that rpm gives you a too high trolling speed, the only 'normal' option is to change prop to one with lower pitch.
The idle mix setting however you have to do in neutral, boat still in water.
While adjusting, try to keep the rpm as low as possible.
Before adjusting, run the engine with Sea Foam or Engine Tuner and be sure water pump and thermostat is in perfect working condition.
The Boyesen reeds will probably alter the setting compared to the factory setting, but the way of adjusting is the same.
 
(Carburetor Adjustment - Single S/S Adjustable Needle Valve)
(J. Reeves)
Initial setting is: Slow speed = seat gently, then open 1-1/2 turns.

Start engine and set the rpms to where it just stays running. In segments of 1/8 turns, start to turn the S/S needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running.

Eventually you'll hit the point where the engine wants to die out or it will spit back (sounds like a mild backfire). At that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

Note 1: As a final double check setting of the slow speed valve(s), if the engine has more than one carburetor, do not attempt to gradually adjust all of the valves/carburetors at the same time. Do one at a time until you hit the above response (die out or spit back), then go on to the next valve/carburetor. It may be necessary to back out "all" of the slow speed adjustable needle valves 1/8 turn before doing this final adjustment due to the fact that one of the valves might be initially set ever so slightly lean.

Note 2: If the engine should be a three (3) cylinder engine with three (3) carburetors, start the adjustment sequence with the center carburetor.
When you have finished the above adjustment, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.

Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay auction at:

http://shop.ebay.com/Joe_OMC32/m.html?_dmd=1&_ipg=50&_sop=12&_rdc=1
 
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