Throttle Cable Question

DUKE1

Petty Officer 3rd Class
Joined
Jul 30, 2006
Messages
96
Hello All,
I'm running twin 140 Johnson Loopers on a 24 Grady White. The engines are 86's and counter-rotating. I just put new SST props on them 14 1/2 X 19 and have noticed that the right engine will top out at 5600 RPM while the left will easily do the max 6000 rpm. I have the dual controls on the remote and the left goes to 100%, while the right I can only get to about 80 % before it stops. So the question is this....is the problem with the throttle cable length? or is it in the remote? Could the right engine throttle cable be going on me? Everything is smooth in operation. Compression is 140 in all four on the left and 130/135 on the right. Any help would be appreciated. Thanks
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,771
Re: Throttle Cable Question

Open the throttle fully. Remove the air box and verify that the throttle plates are perfectly horizontal. If not, cable adjustment is necessary. Put the control in neutral. Disconnect the throttle cable. Push the throttle linkage against its idle stop. Bring the cable end up to the throttle linkage. If it doesn't match up perfectly, adjust the trunion (threaded barrel) so it does. Then connect the cable. If you have to move the engine linkage or push or pull the throttle cable to attach it you've done it wrong. Attach the cable and now check for full throttle. If it still doesn't open fully, you need to start from scratch with link & sync.
 

DUKE1

Petty Officer 3rd Class
Joined
Jul 30, 2006
Messages
96
Re: Throttle Cable Question

Thanks Silvertip,

So if the throttle plates are perfectly horizontal when I do this, does this mean the engine is giving what it can and I need to look elsewhere for more RPM's (like in the prop?)
 

DUKE1

Petty Officer 3rd Class
Joined
Jul 30, 2006
Messages
96
Re: Throttle Cable Question

Well I checked the left engine after taking off the airbox and noticed that the throttle plates opened up to the WOT, and the right engine throttle plates were just shy of WOT. I adjusted the WOT screw on the right engine per the OE manual and it seemed to do the trick. Both engines now open to the proper WOT mark. Now we'll see how they run next week when I get the boat out. Should be fun. Thanks for the help.
 
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