Author Topic: Outboard: high revs when shifting back to Neutral  (Read 368 times)

Offline ChuckD

  • 2nd Watch Helmsman
  • *****
  • Posts: 119
  • Karma: 5
  • Sailing WA's Olympic Peninsula
Outboard: high revs when shifting back to Neutral
« on: March 13, 2017, 01:07:40 AM »
2017 Suzuki DF2.5
. Starts on first pull, idles great.
. I pull away from the dock. Six minutes later I point into the wind, hoist the sails.
. When I shift into Neutral the engine races - really high revs. It'll do that for at least a minute if I let it (even if I goose it a few times).

The problem is:
As I approach the dock, I shift into Neutral to control boat speed (and the engine races). When I re-engage Forward for that final push 20 feet from the dock, the engine slams into gear (as does my mild OCD). And one of us - I think it's the outboard - has a "Sunova!" thought bubble above their head.

Anyone have any ideas why this is happening? Thanks! Chuck
« Last Edit: March 13, 2017, 01:57:29 PM by ChuckD »
s/v Walt Grace (CP16)
Sequim, WA

Offline alsantini

  • Captain
  • *****
  • Posts: 362
  • Karma: 8
  • Sail On
Re: Outboard:
« Reply #1 on: March 13, 2017, 07:50:46 AM »
Chuck:  First a question.  How does the engine move the boat under load?  Does it have the control that it normally has?
I have a thought regarding the racing engine.  Normally if the air fuel ratio is correct an engine will idle and pull well.  However if there is a vacuum leak, the idle will be unusually high.  When this occurs, pull the choke slightly.  If it is a lean condition it will come down with the application of the choke. I would check the carb base nuts.  If one or both are slightly loose, air leaks into the manifold, the A/F ratio goes lean and the speed goes up.  BUT, normally when this happens the ability of the engine to operate under load is usually impacted.  Good luck and keep us all posted when you figure it out.  Sail On.  Al

Offline ChuckD

  • 2nd Watch Helmsman
  • *****
  • Posts: 119
  • Karma: 5
  • Sailing WA's Olympic Peninsula
Re: Outboard:
« Reply #2 on: March 13, 2017, 01:58:31 PM »
Thank you, Al.
She runs great under load!
I'm really happy with the motor's performance, except when shifting back into Neutral. (And it's done the high-rev thing since day 1.)

I will check out carb base nuts - thanks!
Chuck
s/v Walt Grace (CP16)
Sequim, WA

Offline mikew

  • 2nd Watch Helmsman
  • *****
  • Posts: 132
  • Karma: 6
Re: Outboard: high revs when shifting back to Neutral
« Reply #3 on: March 13, 2017, 07:58:47 PM »
Chuck,no direct experience but found the following. Checked on other forums on the 2.5 hp, and other owners report a common problem is stalling under load. So if you turned down the idle stop screw  at neutral to normal idle speed would the engine stall under load.? They report the fix is to
adjust mixture screw on carb  which is under a fixed metal cap that needs to be drilled out to access mixture screw. Found a you tube link to this : http://youtu.be/o2xpV9CJCNc
But if engine is 2017 maybe this would void warranty, bring to dealer first.?
Is it possible that from day 1 the idle was turned up by the dealer to mask this problem ?

Mike
« Last Edit: March 13, 2017, 08:53:41 PM by mikew »

Offline ChuckD

  • 2nd Watch Helmsman
  • *****
  • Posts: 119
  • Karma: 5
  • Sailing WA's Olympic Peninsula
Re: Outboard: high revs when shifting back to Neutral
« Reply #4 on: March 14, 2017, 12:48:02 AM »
Mike, thanks.
The idle is perfect until I shift from Froward to Neutral.
s/v Walt Grace (CP16)
Sequim, WA

Offline ChuckD

  • 2nd Watch Helmsman
  • *****
  • Posts: 119
  • Karma: 5
  • Sailing WA's Olympic Peninsula
Re: Outboard: high revs when shifting back to Neutral
« Reply #5 on: March 17, 2017, 11:25:31 PM »
Guys - thank all of you for your input!
I posed this question on 3 other popular forums...
Had hundreds of Views, but but one Reply!

Leave it to CPYOA to come through.
Good Karma to each & every one of you!
Chuck
s/v Walt Grace (CP16)
Sequim, WA

Offline alsantini

  • Captain
  • *****
  • Posts: 362
  • Karma: 8
  • Sail On
Re: Outboard: high revs when shifting back to Neutral
« Reply #6 on: March 23, 2017, 08:40:38 AM »
Chuck:  Any final words on the outboard?  I (we) are always interested in what really was going on and the final disposition of the problem.  I spent some time on my old outboard a few days ago, mostly checking it over and it made me wonder what went on with yours.  Sail On      Al

Offline ChuckD

  • 2nd Watch Helmsman
  • *****
  • Posts: 119
  • Karma: 5
  • Sailing WA's Olympic Peninsula
Re: Outboard: high revs when shifting back to Neutral
« Reply #7 on: March 23, 2017, 01:38:34 PM »
Al,
Thank you for checking in!
I was worried that I'd have to monkey with the air/fuel ratio - which would have meant drilling the tiny factory-sealed cover off the hidden screw. But I'm happy (and a tad embarrassed) to report that - by simply back off the Idle screw - I think I solved it! She now shifts from Forward to Neutral with no racing or subsequent gear-slamming.

Al, thanks again - you're a class act!
Chuck
s/v Walt Grace (CP16)
Sequim, WA

Offline alsantini

  • Captain
  • *****
  • Posts: 362
  • Karma: 8
  • Sail On
Re: Outboard: high revs when shifting back to Neutral
« Reply #8 on: March 25, 2017, 06:23:54 AM »
Cool Chuck.  I love a simple problem.  I try real hard to keep my 4 hp 4 stroke functioning well and keep a mental file of what fixed various problems.  I am a technical trainer for a company that manufactures automotive training aides and a retired automotive electronics instructor and have seen many really tough and strange problems, so it is great to see a simple fix that works.
I had an interesting encounter yesterday regarding my old motor.  During the summer I am in a marina that is pretty tight, so the owner requires that motor NOT be left tilted out of the water.  So for years my motor has sat in the relatively stagnant water.  The cover is really sun faded, and the lower end has stains from the water BUT, it runs well.  I have done all the maintenance on it including synthetic oil, plugs, water pumps, etc and I only use non-ethanol fuel.  As I was flushing the salt water out of the motor, someone, that I do not know walked up with his dog. He looked at the boat, looked at the motor and announced that he would not go out into the Gulf with a motor that looked that bad. And this is while the motor is purring along at a fast idle.  I decided to NOT let him hear a word out of me and continued to wash the salt off the hull.  After letting his dog pee on my trailer tire, he walked off. Surrounded by experts, I somehow continue to sail without killing myself.  Just luck, I guess. LOL
Have a great sailing season and Sail On....    Al

Offline ChuckD

  • 2nd Watch Helmsman
  • *****
  • Posts: 119
  • Karma: 5
  • Sailing WA's Olympic Peninsula
Re: Outboard: high revs when shifting back to Neutral
« Reply #9 on: March 25, 2017, 04:52:11 PM »
"It takes a man to suffer ignorance and smile..."
Sting Englishman in NY

You took the high road - a sign of wisdom! It's really easy to fire back a retort.

I think it's kinda magical when something is perceived as ugly - but purrs year after year. That doesn't happen by accident!
Bravo Zulu, Al!
s/v Walt Grace (CP16)
Sequim, WA