4.3 LX Merc- Trouble Setting Idle

1995, 4.3 Mercruiser LX, Serial # OF421280
Idle is 1200 RPM on muffs. Owner's Manual says idle should be 650-700 RPM IN GEAR.
On muffs, I have tried to set the idle back using the adjusting screwl. What I noticed is that there seems to be "play" in the linkage. (Throttle cable seems OK, but the play in the linkage, between the cable, through to the linkage rods is just enough to keep the engine running at 1200 RPM.
All I have to do is press lightly on the linkage, and the linkage moves against the set screw, and the idle drops to 700 RPM. I have tried lubricating all the hinge points in the linkage, but no change yet. Nothing seems to be binding.
Questions:
1) Anything else I can adjust?
2) When I put the engine in water, in gear, still at idle speed, will the slack in the throttle cable and linkage disappear.
Thanks

Re: 4.3 LX Merc- Trouble Setting Idle

Ayuh,........

Isn't that 650/ 700rpms,... In Gear, In the Water, Under Load,..??.........

Re: 4.3 LX Merc- Trouble Setting Idle

This problem seems new this year. Boat has just come out of storage.
Last week, I had the boat in the water, and it was revving at 1200 RPM at the launch- same as when on muffs at home. At that time, I had a tach problem, so I wasn't sure about the RPM's. Tightened the loose wire on tach, and confirmed that engine is actually idling at 1200.
When I lighly touch the throttle at the carb, it will drop to 700 RPM's and it sounds right too. When I touch it, I am only moving it, freely, probably 1/16".

1200 seems a little high to start shifting into gear.
Comparing to a typical automotive setup, I find that the linkage is not being pulled back firmly against the idle set screw. I'm not sure how to get rid of the slop. My manual shows the carb, and thre throttle cable, but not the linkage. Almost seems like the throttle cable has to "push" the linkage against the throttle set screw, instead of a return spring "pulling" it against the idle set screw.
(I will attach a picture to this post tonight)

Re: 4.3 LX Merc- Trouble Setting Idle

If it needs more Push,........ Lengthen the Cable........

Re: 4.3 LX Merc- Trouble Setting Idle

1)Disconnect the throttle cable/linkage.
2)Adjust idle speed
3)Adjust and reconnect throttle cable/linkage.

Re: 4.3 LX Merc- Trouble Setting Idle



AFTER you disconnect the throttle linkage and adjust the idle speed without the cable attached, as Fishstick stated, THEN Adjust cable barrel ( C ) to put a SLIGHT preload on the carb linkage in the idle position.

Re: 4.3 LX Merc- Trouble Setting Idle

Thanks, Don. The picture is exactly what I have in the boat(and need to make the adjustment) My Seloc manual showed the carburetor arrangement and the throttle cable, but nothing in-between.