Another throttle problem?

[alandry100]

My "new" 2005 Yamaha 70 with a 704 binnacle has had a couple of throttle issues. One the throttle creeps back to idle unless trimmed perfect and in near glass conditions.  This has been fixed after reading a recent thread - I think - by increasing tension on the under cover screw. Before there was lots of "back-play". My question is if this likely fixed the other problem - which is - that I can only get 4800-5000 rpm at full throttle and optimal trim. RPM's max out at about 3/4 throttle. The manual says I should be at the top half of the 5000-6000 max output. Any help is appreciated.

[seabob4]

Take your cowling off, advance the throttle lever to WOT and note the position of the end of the throttle cable.  Now, remove the cable from it's mounting stud and move the throttle linkage on the motor.  See if you have more travel.  If so, you need to adjust the adapter on the end of the cable to allow the linkage to get to WOT...

[alandry100]

Thanks Bob - I popped the clip out, removed the linkage and loosened the end that slips over. Even backed all the way off the throttle is about an 1/8" from the stop. Any further and I'm not sure if it has enough thread. I think the adjustment is a little more in depth. Maybe this is all I need however, I am going to test tomorrow.

[seabob4]

You may have to make adjustments at the binnacle end to get more thread.  The way I rig Yam binnacles is so that the threaded end of the cable is basically flush with the bottom of the hollow opening in the adapter.  Then I do any adjustments at the motor end.  This gives me plenty of thread to make adjustments in or out...

[alandry100]

Thanks - I will check - I am sure it will become more clear when I look at it but I get a bit confused talking about these things without looking at it because I'm not really sure what any of the pieces are called.

[alandry100]

The throttle creep is definitely fixed. The top end issue has not. After tightening the end of the throttle attachment, put the boat in and the whole throttle was sped up. She was idling at 1500 rpm and would not sit go into neutral. The launch was busy so I moved off a bit, cut the engine and backed it off a bit. Presto - idle was down to 1000 - which too high, dialed it in at 800 in a later adjustment. I still cannot get over 5000 RPM and she maxes out at around 3/4 throttle. Is there a top end adjustment as opposed to a whole shebang adjustment. Time to but a Clymer.

[seabob4]

Just out of curiosity.  The PO may have readjusted the WOT stop on the throttle linkage to only allow the boat to go so fast, read that kids.  With the engine off, advance the throttle to WOT, and see if the stop is hard against the block.  Then start backing off the limit on the linkage, see where this gets you...

[alandry100]

It is not hard against the block - looks like around 1/8" to 1/4" to go. Which linkage do I adjust?

[seabob4]

It is not hard against the block - looks like around 1/8" to 1/4" to go. Which linkage do I adjust?

There should be a jam nut on the other side of the arm that the stop threads into.  Loosen that nut, then back out the stop until it rests against the block at WOT.  Tighten the jam nut back up.  Won't be able to tell the effects until you get her out on the water...

[alandry100]

Thanks seabob. Will get at it this weekend.

[alandry100]

Got the throttle adjusted properly - getting 5100 at WOT. Seems good enough to me. Has plenty of punch. I will not be running WOT that often. Took in to the bay this week - ran all day at 4000 - 4400 because of big rollers and  chop - burned 8 gal. all day (3 hrs on the engine - some idling). On the lake running 4800 - might burn 12 running about the same time. I love the 70. Thanks for the help.