Idling High

wilson973

Cadet
Joined
May 22, 2010
Messages
24
Just put my motor 1989 Johnson 70Hp Back together. Had it bored .030 over. Fired right up. The only problem is when idling it is idling high. If I go to the motor and push the timing bar ( I quess thats what it is ) Back it will idle down. As soon as I let it go It idles back up. Any advice?
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: Idling High

Idling how high (what rpm)? In the water or on a flushette?
 

wilson973

Cadet
Joined
May 22, 2010
Messages
24
Re: Idling High

It is idling Just above a normal idle . But high enough to know it is high. I have run it for about 10 mins. on the flush ears. I have no way of knowing the RMPs. If I had to quess I would say about 2x the idle RPM.
 

Haffiman

Commander
Joined
Dec 17, 2009
Messages
2,454
Re: Idling High

If you are using your 'old' setting before re-bore, I'm not surprised.
Do a link and synch and re-adjust.
The idle the has to be set when the boat is back in water.
 

Rick.

Captain
Joined
Jul 30, 2006
Messages
3,740
Re: Idling High

You may well find it is correct when you have it in the water with some back pressure. It must be set a little higher on muffs and final adjustments made on the water, in gear and boat moving. Best of luck. Rick.
 

wilson973

Cadet
Joined
May 22, 2010
Messages
24
Re: Idling High

Before I rebuilt my motor it idled just fine on the muffs. I dont know how to adjust the idle on my motor. I have the throttle cable fully adjusted. It is barely touching the carb linkage. I cant go any futher with the adjustment that way, it is fully extended. Not even touching the linkage. How do you adjust the carbs any other way. 1989 Johnson 70HP J70TLCEM
 

Haffiman

Commander
Joined
Dec 17, 2009
Messages
2,454
Re: Idling High

May I suggest you get an OEM workshop manual and read about 'link and synch'.
Rebuilding an engine without performing the most basic of adjustments may soon kill it again.
Here some 'hints'.
Get the timing pick up point correctly adjusted.
(Timing when carbs starts to open, carb roller is at the mark of the cam)
Then adjust the idle by simply reduce timing advance.
Unhook the throttle cable from the engine and put a rubber band on the throttle arm keeping it against the stop while adjusting.
When everything is properly adjusted (boat in water, engine in gear and boat moving freely), re-adjust the throttle cable and hook it back on.
 

wilson973

Cadet
Joined
May 22, 2010
Messages
24
Re: Idling High

OK Just ordered the Selco Repair manual for my boat. But would really like to go shrimping this weekend with my kids. Can anyone please tell me how to adjust the timing on my motor? Do I need to pull the fly wheel and what to do.
 

mrcj001

Petty Officer 1st Class
Joined
Jul 25, 2008
Messages
313
Re: Idling High

OK Just ordered the Selco Repair manual for my boat. But would really like to go shrimping this weekend with my kids. Can anyone please tell me how to adjust the timing on my motor? Do I need to pull the fly wheel and what to do.


Cancel that order on the Selco Manual...it is useless

You will need a OMC Service Manual. You can order one here:

http://www.outboardbooks.com/

Try to get you going:

Disconnect the throttle cable at the engine:

Start engine and adjust the idle with the idle adjustment screw located on the throttle lever.

Reconnect the throttle cable to the lever. You may have to adjust the cable back or forth so it doesnt have much backlash and fits the throttle lever with out moving it.

With the engine off. Move the throttle on the remote to WOT and then return to idle, while watching it. It should return the throttle lever at the engine right on the throttle stop. If not re-adjust till it does.

Make sure the cam follower is not opening up the carb throttle valves at idle.

The first mark should be right in the middle of the cam roller. When you lift up on the warm-up lever, it should only move to the "START" mark.

You will need to have the engine under load, (in the water) to do the final idle adjustments.
 

wilson973

Cadet
Joined
May 22, 2010
Messages
24
Re: Idling High

My carbs are adjusted properly. Butterflys are straight up and down at idle. Start to move when I move my throttle cable. There is no play in thelinkage at all. When idling it is idling about 2x higher tha what it use to idle at. If i push the Timer Base Assy. lever back it idles down to what sounds normal. But when I let it go it goes back to the original position and idles up again. Is there a way to adjust the timing on this motor?
 
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