Yamaha 150ETLG Pro-V NEED HELP!

EleSSaR

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May 2, 2010
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Hello everyone I am new to the forum glad to join a bunch of knowledgable gentlemen as yourselves. So hears what I have for you Im sure you have heard it a million times. But I really need the help.

Take the boat out first weekend of the year using premium fuel, stabil, and quicksilver two cycle oil 50:1 Runs like a champ.

Second time out motor begins surging at WOT. Almost like someone flicking a switch on and off hit 4500 drop to 38 instantly pick back up and drop, So I thought surely fuel is the problem. So I brought it home replaced everything from the tube pick all the way to the fuel pumps. Everythings tight no leaks no air.

So I take it out today go for wot motors a little hesitant getting off the line but does once it does it runs up to 4200 and like a switch first it falls to 3800 and then like a second switch falls to 3200 and will stay there all day no problem no missing overheating alarms nothing.

So as soon as is starts dropping I checked the inline fuel filter it was full and the fuel primer bulb was still firm. The carberators were all taken off and cleaned they were freshly rebuilt last year. I noticed like someone else did when I took my front cover off I had some oil/fuel residue left on the face of the cover attached to the carbs. I'm going to replace pumps but if the inline was still full and the bulb still firm could that be the problem. Checked vent valve I could blow through it no problems checked pickup tube and replaced fuel lines.

Idles great real smooth usually no hesitation when coming off the line just started that this time around. The plugs were a little black around the edges but the electrodes were tan when I took em out and cleaned them. I don't know I'm lost and I know nothing bout the electronics. My alternator is charging well stays at or around 13v when wide open.
 

99yam40

Fleet Admiral
Joined
Sep 7, 2008
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9,195
Re: Yamaha 150ETLG Pro-V NEED HELP!

My thoughts are to pull and clean carbs, last year was last year. Most problems are fuel related. If you run a motor lean because of plugging jets /passages it will eat pistons.

The best way to trouble shoot motor problems is to make sure compression and spark is good on all cylinders and if they are look at fuel. Some testing needs to be done while the problem is occurring

If you really want to check the other systems properly then buy a manual for your motor and get the proper test equipment. follow the procedures step by step. So many people do not do this and this causes frustration and part replacements that are not needed.

Do some searching of the forum on surging.
 

EleSSaR

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May 2, 2010
Messages
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Re: Yamaha 150ETLG Pro-V NEED HELP!

Thanks for the help YAM40. I went through and inspected everything along with the fuel pumps and in one I found a pin hole. When I blew air though the back it would put fuel on the part of the diaphram I could see. Wiped it off and did it again same results. Inspected the other pump held pressure and no appearence of leaking. So im going to guess im in the need of a rebuild kit for the pumps. If anyone knows where I can find one or two I need to buy them or would you all reccomend buying all new pumps already put together. I am still curious can the two small pin holes in the one pump cause surging but allow the engine to run and idle perfect at any other time?

Thanks for the help.
 

99yam40

Fleet Admiral
Joined
Sep 7, 2008
Messages
9,195
Re: Yamaha 150ETLG Pro-V NEED HELP!

Could cause fuel starvation if not working properly at higher RPM. Check priceing and see what you want to do . Shops usually relace with new because after the labor is added in the new one is cheaper
 

EleSSaR

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Joined
May 2, 2010
Messages
5
Re: Yamaha 150ETLG Pro-V NEED HELP!

Thanks again YAM40. I found new pumps on ebay I have bought for replacement. I have taken apart all my carbs and am going to soak them in berrymens cleaner over the next couple days and put back together. From what I have seen the carbs are all clean inside and out but just in case after the soak going to blow them out with carb cleaner followed by air. Question is what are the setting for the idle screws I have heard 1 1/8 on the port and 1 5/8 on the starboard have any idea if this is correct?

Thanks again for all the help.
 

EleSSaR

Recruit
Joined
May 2, 2010
Messages
5
Re: Yamaha 150ETLG Pro-V NEED HELP!

OK I have a new problem last night I managed to break one of the jets in my carb. I need to know what the proper name for it is. It is located under the plate on top with the single screw. It has the number 210 on it. There are two of them side by side. I can't seem to find one for replacement need help. Thanks Alot
 

EleSSaR

Recruit
Joined
May 2, 2010
Messages
5
Re: Yamaha 150ETLG Pro-V NEED HELP!

It's finally over, after replacing every single piece of fuel line from the tank back including new fuel pumps and rebuilding carbs, my surge is over and the motor is running better then it ever has since I have owned it. Motors now running upwards of 5300 rpm trimmed up(short period of time) and idles smooth and is now much more quiet then it ever has been of course fuel consumption went up but thats prolly just my right hand talking. I just want to say thanks to those guys who got on here and offered the help and information they did to help me trouble shoot. In total I guess it cost me about $100 to replace the entire fuel system. Sure does beat buying stators, and coil packs so thanks to all for the help.
 
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