# Yamaha 150 2-stroke Idle Question



## johnson867

I have a 2000 model Yamaha 150 that I can't seem to get to idle correctly once warmed up and in the water. I had the fuel pumps replaced last year and replaced the plugs. I set the idle around 1000 out of water and when I first put the boat in the water, it idles around 750 (where it should). But once it has warmed up good, it drops to around 550 rpm. I've tried adjusting the idle while it was in the water, but the idle screw has no effect on it. The idle screw seems to work fine while I'm out of the water. I know it should drop around 200 rpm once in the water. Does anyone have any other options to try. The motor runs great other than the low idle.


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## Sequoiha

it sounds like the sync on the carbs is out of wack...bring it on in and I can take care of it for you,,,, by the way.. 1000 rpms out of the water is way to fast.... :usaflag


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## DOUBLE "D" & LV

once the engine warms up, it should drop to around 800 out of the water. I agree with Kenny. Sounds like a linkage synch issue. I also recommend letting someone experienced to adjust them. If you do not adjust them correctly, then you run the risk of lower unit gear damage.


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## fish4life

Livingston's Outboard Rebuilds & Repair



Give me a call 850-968-6580 I can fix it for you. $40hr thats half of what you are going to pay at a marina.


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## Tuna Man

> *DOUBLE "D" & LV (6/17/2008)*once the engine warms up, it should drop to around 800 out of the water. I agree with Kenny. Sounds like a linkage synch issue. I also recommend letting someone experienced to adjust them. If you do not adjust them correctly, then you run the risk of lower unit gear damage.


For future reference....Please explain!


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## Sequoiha

He means because of the high idle the lower unit will slam into gear... it needs to be around 750 plus or minus 50,,,:usaflag


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## Sequoiha

> *fish4life (6/18/2008)*Livingston's Outboard Rebuilds & Repair
> 
> Give me a call 850-968-6580 I can fix it for you. $40hr thats half of what you are going to pay at a marina.


thats actually less than half you will pay at a marine repair facility,,, you are the same person that spammed my personal inbox..

just so you know, you come on this forum with a total of 8 posts and advertise outboard repair for 40 dollars an hour,, No hard feelings but I hope you dont get any work,, you get what you pay for,,, actually I hope you get all the work you can handle,, then when your 40 dollars an hour cant fix it they will bring it to one of the several seasoned and respected mechanics on this board.. just my .02:usaflag


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## Tuna Man

> *Sequoiha (6/19/2008)*
> 
> 
> 
> *fish4life (6/18/2008)*Livingston's Outboard Rebuilds & Repair
> 
> Give me a call 850-968-6580 I can fix it for you. $40hr thats half of what you are going to pay at a marina.
> 
> 
> 
> "you are the same person that spammed my personal inbox" ..
Click to expand...

You got to be kidding me:banghead:banghead...Of course I'm just oke at you.

Thanks for explaining that....I didn't know or think about that:doh

Now this has nothing to do with this situation, but for information....I was in the doctors office yesterday (6 month check up...all good..funny story but for another post) and while waiting, picked up a boating magazine and was reading (you know when waiting you have time to read *<U>War and Peace</U>* from cover to cover) Well I'll scan the Q & A section. I had them make a copy of the 2 pages.


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## DOUBLE "D" & LV

Thank you Kenny. Yes, that is what I meant. I will try to elaborate more in the future. I hate when when the info is not there also. OOOOPS.

I'll stop in soon to see how you guys are doing Kenny.


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## flipthelip

call Posner 850-444-9760 at least they will set you in the right direction:bowdown


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## Sequoiha

> *flipthelip (6/19/2008)*call Posner 850-444-9760 at least they will set you in the right direction:bowdown


They are one of the seasoned and respected people i was referring to...:usaflag

are you saying I didnt set him in the right direction,,, I do believe I was the first person to actually answer his question... thank you very much....


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## Sequoiha

> *Tuna Man (6/19/2008)*
> 
> 
> 
> *Sequoiha (6/19/2008)*
> 
> 
> 
> *fish4life (6/18/2008)*Livingston's Outboard Rebuilds & Repair
> 
> Give me a call 850-968-6580 I can fix it for you. $40hr thats half of what you are going to pay at a marina.
> 
> 
> 
> "you are the same person that spammed my personal inbox" ..
> 
> Click to expand...
> 
> You got to be kidding me:banghead:banghead...Of course I'm just oke at you:
> 
> Yup,, I get up Monday Morning and that is in my In Box... I wrote him and told him not to spam me, he writes me back and says "I am no spam..." I told him it was in my box, I did not ask for it there for it is spam and not to do it again.... havnt heard back...
> 
> :usaflag
Click to expand...


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## nic247nite

$40.00 and hour I hope he can pay for gas, parts, car insurance, business ins. Etc.....:banghead


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## DEVILer

I have a 2005 Yamaha 150hp. 2 cycle. (150 TXR) Authorized Yamaha mechanic.. in the shop... engine will not idle... they have cleaned carbs a number of times and still no good. they says two cylinders are not firing. It runs great at high speed. 5500 rpm is not a problem. They want to pull the head for a look see... mentioned about not enough vacuum due to scoring of (piston/cylinder). could the head gasket be bad? any other ideas? I close to $1000 repair to date!


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## bfish

See if the spark plugs fire while out and grounded. Could be no fire


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## bfish

Maybe the IAC. (Idle air control)


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## murfpcola

Seems like a compression check would tell whether or not the heads need pulling


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## kanaka

I think it broke 10 years ago.........


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## H2OMARK

11 year old thread being brought back up by a first poster.


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## CurDog

DEVILer said:


> I have a 2005 Yamaha 150hp. 2 cycle. (150 TXR) Authorized Yamaha mechanic.. in the shop... engine will not idle... they have cleaned carbs a number of times and still no good. they says two cylinders are not firing. It runs great at high speed. 5500 rpm is not a problem. They want to pull the head for a look see... mentioned about not enough vacuum due to scoring of (piston/cylinder). could the head gasket be bad? any other ideas? I close to $1000 repair to date!





murfpcola said:


> Seems like a compression check would tell whether or not the heads need pulling



^^^That's what they need to do ^^^ a compression test. 

Seems they are taking you for a ride. $1k into it and they want to charge you for trial and error checks? Hmm, maybe it's the coil, lets replace it, charge for them and labor. Oops, wasn't that, oh well lets try the other one, hmm, wasn't that, let's pull the flywheel, maybe the trigger is shortening out? Oops wasn't that either. 
There's no way I would pay some "authorized" mechanic to troubleshoot until he figures out what is wrong. If they do, then you should only be charged for the problem repair, not their ignorance.


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## H2OMARK

South Jersey? Hell that's not to far to bring it down here to Kenny. Only 2 people have worked on my boats, Scott Brech and Kenny Mann. Both are the best in the business.


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## holicori

CurDog said:


> ^^^That's what they need to do ^^^ a compression test.
> 
> Seems they are taking you for a ride. $1k into it and they want to charge you for trial and error checks? Hmm, maybe it's the coil, lets replace it, charge for them and labor. Oops, wasn't that, oh well lets try the other one, hmm, wasn't that, let's pull the flywheel, maybe the trigger is shortening out? Oops wasn't that either.
> There's no way I would pay some "authorized" mechanic to troubleshoot until he figures out what is wrong. If they do, then you should only be charged for the problem repair, not their ignorance.


Yup. I've had to eat parts and labor before because I've overlooked a diagnosis and got it wrong before. Invoice reflects the true repair parts/prices. 

I'd let an inferior tech throw parts at my ...whatever....all day if the bill only showed what was the real fix/repair bill....but I've never seen that before. 

Sent from my Moto Z (2) using Tapatalk


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## CurDog

Exactly right. You are at their mercy, that why I work on my own. If it's something major and I know 100% what the problem is, then I'll take it to a mechanic. 

DEVELer, try this. Put the motor on water muffs, run the water, start your motor. Trim All the way Down, listen for a change in rpms. 
Then slowly start trimming up, If the rpms start to get worse or picks up in idle, the likely cause is one of your floats is out of alignment, barely noticeably cocked to one side. The float pin is not setting in the cradle perfectly. Could be a half grain of sand or someone in a hurry to tighten it down. 

I know, you said the carbs have been gone thru already. I've seen this problem only 1 time before, and the carbs were rebuilt twice at authorized marina, once by another authorized marina and problem solved by a third authorized repair shop. They rebuilt carbs once, then went back and doubled checked the pins. 
Maybe yours has the same problem? But have them to do the compression test before they tear down your engine "looking".


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