carb sync on 3cyl and v4

[mikesjohnson]

i have 2 79 OMC out boards. one a johnson 115 and one a evinrude 70. ever since i have had both of these engines, they both load up at idle. the 3cyl does it on the bottom cyl. i have been trying to find some info on how to synch the carbs, but have yet to find squat. can someone help?

 

[Silvertip]

Re: carb sync on 3cyl and v4

All the knob twiddling in the world can't make a pooly running engine better if the carbs are in need of rebuilding. Weak spark is another problem that can't be solved with adjustments. So -- if that's been done, then you need an OEM service manual so you can perform a Link & Sync procedure that syncs the carbs not only with each other, but with engine timing. That procedure also covers idle speed and idle mixture adjustments where mixture is actually adjustable. That procedure is far too detailed to go into here. If you don't want the convenience and help of a factory manual, you can visit your local library. They often have a selection of service manuals but they may not have one specifically for your engine. You would at least get an idea what's involved. You might even try e-bay.

 

[seahorse5]

Re: carb sync on 3cyl and v4

Have you checked the operating temperature on both motors to make sure they are running about 140° at idle?

Have you removed, tested, and cleaned the recirculation valves, hoses, and fittings on the 115?

This is assuming that your motors are in good shape, as well as the carbs, linkage, and igntion system.