Motor Idling high rpm

[lighthouse2k]

I have a Mercury Saltwater 115 2 stroke. I slipped it out of gear the other day and it started to idle higher in the rev range, around 1300rpm and hasn't stopped. I was moving it in and out of gear a bit at the time getting someone to a jetty. Other than that its fine, starts ok, runs ok etc but obviously too high. I this an easy fix with the idle adjustment? Why did it happen in the first place? Newish engine, 70 hours.

Thanks

Chris

[Roughasguts]

Mate it shouldn't slip out of gear.

Something has come out of adjustment in your throttle, and gear selection linkage, Maybe just caused by the cable stretching over time, or a kink, dirty many reasons, even just a lube can fix it.

So for a quick check put in neutral and spin the prop if it clicks, that linkage will need to be adjusted So it doesn't wear the dog gear.

Also the throttle linkage see if you can close the throttle more by just moving the linkage, if you can that be why the idle is up.

It should be a easy job 2 mins.

[lighthouse2k]

Just to clarify, it did not slip. I moved the control lever from forward to neutral and it was revving higher. Thanks for your advice though.

Chris

[Spaniard_King]

Roughasguts, your showing good form ;D ;D ;D

Chris, could be any thing or numvber of things causing the increse in rpm. Things like

Intake air leak
Incorrect throttle link & Sync adjustment
Carby problems

Just to name a few :-/

Unless you are familiar with 2 strokes you maybe better off getting someone else to look at it.

cheers

Garry

[Al_Macka]

B taking it doctor ( O/B mechanic ) he's the bloke that will show u
why & wot caused problem...... & or if this could hav done further
damage down the road ...... Sounds only minor but pro help does a lot 4 peace @ mine ....... Especially if ur fish'n haunts are serious kkkk's

CHEER'S............... MACKA

[Roughasguts]

Roughasguts, your showing good form ;D ;D ;D

Chris, could be any thing or numvber of things causing the increse in rpm. Things like

Intake air leak
Incorrect throttle link & Sync adjustment
Carby problems

Just to name a few :-


Unless you are familiar with 2 strokes you maybe better off getting someone else to look at it.

cheers

Garry

Self proclaimed King of the spaniards.
I am happy to be proven wrong, as long as sombody gets the answer to lighthouse's problems.

But you just delivered a heap of open ended answers.

Could you be more specific.
You sound like a Doctor with the diagnosis
"Yep sounds like it's got a Virus".
In other words Dont Know!

[lighthouse2k]

Took it down the ramp, screwed the idle screw right in. At idle in neutral it is sitting under 1000 rpm.

In gear it is sitting just under 800rpm. Factory recommendations are 650 to 700 rpm. Can't remember what its been sitting on before it started to idle high.

As I said before, everything else else appears to be fine throughout the rev range.

Chris

[Roughasguts]

How many idle screws did you find ?

Or did you screw the one, idle adjustment on the linkage for all carbs
EG linkage throttle stop.

I hope it was this one. That was what I was sugesting in the first place.

[lighthouse2k]

I did the one which had the white sticker marked idle adjustment ;) Did actually have it marked on there so I would imagine this would be the right one. I was on the long throttle linkage. I imagine I really need to adjust the throttle cable overall in the longer run.

[Spaniard_King]

Roughasguts, your showing good form ;D ;D ;D

Chris, could be any thing or numvber of things causing the increse in rpm. Things like

Intake air leak
Incorrect throttle link & Sync adjustment
Carby problems

Just to name a few :-


Unless you are familiar with 2 strokes you maybe better off getting someone else to look at it.

cheers

Garry

Self proclaimed King of the spaniards.
I am happy to be proven wrong, as long as sombody gets the answer to lighthouse's problems.

But you just delivered a heap of open ended answers.

Could you be more specific.
You sound like a Doctor with the diagnosis
"Yep sounds like it's got a Virus".
In other words Dont Know!


"Roughas"

I don't want to give the guy the "WRONG" answer espeacially if I havent seen the engine. Why lead the guy down the garden path ::) ::)
You obviously are a master of outboard repair and maintenance who can diagnose faults through his computer :o With such a talent I recon you stand to be a rich person one day ::)

As far as recommendations go this is my last post in helping someone out. I will leave it all to you.. good luck :-X

Garry

[Roughasguts]

Spaniard King,
I'm sorry you can dish it out, but haven't got the sence of humour to receive it back.

If your frightened to give the "wrong" answer to a thread then why reply at all. It just seems you prefer to mock someone that does.

Why not probe the poster with more questions until your satisfied you can give an anwer that would be most likely.
After all that is why they post in the first place isn't it.

I'm sure this is not the last the board sees of you,
I hope not for my part.

[Spaniard_King]

Roughas,

I suggest you read my post again

Garry

[HarryO]

Hey all...

C'mon fellas, remember the love..... #:)

Just for the record, Garrys first post was pretty much spot on. #8-)

Some of the smallest problems can be bloody
difficult to diagnose over the keyboard... #:-/

To advise someone who has limited mechanical experience
with the larger 2 strokes to start mucking around with the
link/sync adjustments, etc, #could be a bit like the
Titanic sending out for more ice... :)

If the problem is not obvious by Looking and tweaking,
book it in..
An early service would not do it any further harm.

Harry #:)

[lighthouse2k]

To be fair, the reason I posted this is to see if there is a quick remedy so I don't have to take it in. Its not that I don't mind paying, more the inconvenience of taking it in.

So...........A couple of quick tips to look at some simple things and see if this will remedy or confirm my thoughts is what I was looking for. If I can't get the answer I like or in part agree with I would take it in to get it fixed.

In my book Roughas provided this in part, Spaniard you game me other suggestions but nothing to look for either, so to be honest that was of little help and not too constructive. Not criticism as I don't really care but feedback all the same.

Thanks

Chris

[Spaniard_King]

Chris,

After reading your problem, I made a diagnosis of the problem and posted it to you. having dealt with these types of problems many times before some of them very easy and some very painfull.
I didnt want to lead you down the garden path. Yes you could play with the idle screw but this is very rarely the problem, instructing you on checking the synconization and linkage adjustment for your engine could take a fair while and even some experianced mechanics struggle with it with a book infront of them ::). Generally people who play with these end up in a mess and make it harder for the mechanic to find out the real problem.

You see if you had an idea about what I had posted you probably would have come back to me asking for me to elaborate, don't you agree. I basically tossed a bait out to see what bite I would get.

I just don't see the point in getting your hopes up or getting you to do things that may worsten the problem. As Harry says "get her in for an early service" I hope it all goes well for you

Garry

[finga64]

I'd have to agree with Gary, Macka and Harry here.
Many, many problems seem to be simple but in fact very complicated.
With my trade we have to be very systematic in our diagonists and look at all the aspects of what is happening and what happened in the past.
Sometimes the obvious problem that you see ie fast idle, is nothing like the real problem. It could just be a side effect (and maybe only one of the many side effects) of a larger problem you can't see or notice.

It may well be just an adjustment screw amasingly changing it's setting but that doesn't happen as quick as that as a rule of thumb and from experience.
It's always better to have more information before an accuate evaluation can be made with any problem.
It's also good to gauge the person's mechanical ability before you turn them into Mike the mechanic as well. :)

Each of the items Gary mentioned can be directly targetted and checked with relatively simple checks which have to be done before you can accurately find the problem.
I, for one, never touch adjustments until all other possible problems are ruled out as it can take forever to set up all the adjustments again if they've been messed with.

If the idle had decreased to next to nothing you wouldn't adjust the idle screw to get more revs. You might need to have a new fuel pump or a new primer bulb or a new fuel hose or the fuel filter is clogged or it could as simple as the fuel tank is empty.
So why is it assumed that higher revs is just a idle adjustment or anything to do with the idle settings???

[lighthouse2k]

NO worries its all cool.

[Heath]

All OB problems seem complicated to me.

Thats why I just get Garry round to fix mine :P

[lighthouse2k]

I have read all your posts and to be honest, its all a bit doom and gloom without giving me anything to really and simply look at. As I said before if its not easy to fix I would take it in.

As an example here is a clear and concise explanation of something to check someone sent me which I was really looking for.

"Sounds like the throttle cable has stretched slightly resulting in the throttle arm no longer parking on the throttle stop in the nuetral position.

Take off the cowl and you will easily see the throttle arm (particularly if you have someone work the throttle whilst you are looking).

Unclip the throttle cable from its anchor and spin the barrel nut in the appropriate direction (should be towards the bow) to lengthen the cable and that should solve your problem.

Make sure when you get the cable back to the right length that you put a slight "preload" op possitive pressure on the cable (via the barrel adjuster) to ensure it parks on the throttle stop and is held there with light pressure.

Too much preload can damage the control box. So don't get heavy handed. "

Thanks

Chris

Cheers

[HarryO]

G'day Chris....

A couple of things worth mentioning here..

Very unlikely that a "newish" engine with 70 hours on it
would have a stretched throttle cable...

You would have had other symptoms plainly evident
whilst the cable was "stretching".....

And if the cable was stretched, the net result would be
an early parking of the throttle lever against the idle screw,
not a failure to park.

If the throttle lever was resting against the stop, and you
managed to lower the idle slightly, by adjusting the idle screw,
but not enough, then the problem does not lie in that area.

Enough said..

Harry.

[Itsadungah]

Hey chris, if it is a 4cyl engine it could be leaking fuel injector nipples. Start the motor and crimp the feed hose leading to the injector pump. If they are leaking doing this motor should drop in revs and smooth out. Hope this mite help,
Mal

[Al_Macka]

Hi Chris..........
Please post outcome , when returned from O/B MECHANIC ........... B interested 2 hear solved problem

MACKA

[Al_Macka]

Chris ........... sorry bloke 1 more question . NEWish Engine only 70 hrs .... JUST INTERESTED as why no warrenty,.........& why throttle srews arnt painted @ manufacture 2 see any movement @ these pionts ur play'n wif ........... IF NO MOVEMENT @ DESE pionts me b seek'n PRO HELP .........
DO U TRAVEL OFFSHORE ...... :-/

[Scalem]

Hmmm very interesting thread.

Guy posts up problem - guys answer with suggestions..... Guys debate about the value of those suggestions. It's all relative! It's still up to the person who has the problem whether to take advice or not, it's like "buyer beware" We try and help out wherever we can.

Personally I like to know as much about my outboard as I can without doing a course which costs money, even if I am branded "Mike the Mechanic" - sorry Finga ;) ;) One day, a little bit of knowledge might get you out of trouble out on the water, it's not as if you can get out and push!!

Scalem

[FNQCairns]

Lighthouse you will not fix it by adjusting a screw (there is no 'idle adjustment' screw anyway, it's a concert in there, If you dont know what you are doing really best to see someone who does as what Garry said about air intake or even a deeper leak could cause you lot's of costly trouble.
Your problem is easy for a mechanic to diagnose if they have the engine at hand there are only a few areas to consider.

cheers fnq

[Al_Macka]

Hmmm very interesting thread.

Guy posts up problem - guys answer with suggestions..... #Guys debate about the value of those suggestions. #It's all relative! #It's still up to the person who has the problem whether to take advice or not, it's like "buyer beware" #We try and help out wherever we can.

Personally I like to know as much about my outboard as I can without doing a course which costs money, even if I am branded "Mike the Mechanic" #- sorry Finga ;) ;) #One day, a little bit of knowledge might get you out of trouble out on the water, it's not as if you can get out and push!!

Scalem

WIF NEWISH ENGINE .... CAN NOT UNDER STAND Y NOT SEEKING PRO HELP

SO U KNOW ANSWER .. IF PROP ARISES AGAIN 1 CAN FIX IT ..F%%%%%%

[lighthouse2k]

I thought I would give a reply after all the interesting feedback. After very close examination, the only thing I noticed was the throttle friction adjuster was loose to the point of falling off. I adjusted this back up reasonably tight. I then had to readjust the idle. It has run fine ever since. I recently had it service and they could find absolutely nothing wrong with it. In fact with a new set of plugs it runs even better!!

[Roughasguts]

That's good news lighthouse, think the simple things like a slipped bolt keeping an adjustment, are to often over looked.

People imediately think complexity, and that's where they start looking, and never being able to find the simple fix, staring them in the face.

[boyzie]

get over it you bloody sooks

[Roughasguts]

get over it you bloody sooks

Ahh looks like you haven't. You know theres people who can help you with that.
What you lose your base ball cap or something.