Yamaha 85hp outboard Carb problem...

[laeelin]

My brother-in-law and I now have the use of a boat my dad and uncles bought years ago. The boat itself is in great shape after applying a lot of elbow grease. <br /><br />The problem is the motor.<br /><br />It has been sitting with no use for about 5 years.<br /><br />It turns over fine and you can really feel the compression, so we think (hope) that’s all fine. We also get a nice bright blue-white spark when testing the spark plugs.<br /><br />The engine isn’t firing though.<br /><br />After spraying some fuel in the carb it fired, so something is wrong with the fuel path.<br /><br />We followed the fuel from the plug past the fuel pump to the carb, and are getting fuel all the way to the carb, leaving the jets as the most likely problem.<br /><br />Note: Not sure if this makes any difference, but gas was leaking from the carb/fuel pump area a little bit, and we smelled gas very strongly after we tried to start it for a while. In fact, at first we thought we had flooded the engine.<br /><br />I'm not an expert at all, just trying to use common sense, so any advice is welcome.<br /><br />1) If it is the jets, is this something we can fix/clean ourselves? (Money is really tight after getting a GPS, fish finder, VHF radio, steering cable, ect)<br /><br />2) Is there something else that we should check first?<br /><br />Thanks<br />David

 

[Ray Neudecker]

Re: Yamaha 85hp outboard Carb problem...

Replacing the fuel pump and totally rebuilding the carbs would be my suggestion.

 

[laeelin]

Re: Yamaha 85hp outboard Carb problem...

What kind of price would we be looking at for a carb rebuild kit? (i cant rember the model number and at currently at work)

 

[laeelin]

Re: Yamaha 85hp outboard Carb problem...

oh, and also, how can we check to make sure the fuel pump needs replaceing?<br /><br />The engine has a total of about 10 hours running time on it.. the replaced the old engine and trailer just befoer the stopped useing the boat =)

 

[laeelin]

Re: Yamaha 85hp outboard Carb problem...

Originally posted by Laeelin:<br /> oh, and also, how can we check to make sure the fuel pump needs replaceing?<br />

Think I just found the answer on another post.<br /><br />

<br />If you loosen the bolts that hold it to the engine block and it leaks out the back when you pump the bulb the diaphragm has a hole in it.<br />

 

[rodbolt]

Re: Yamaha 85hp outboard Carb problem...

just replace the pump<br /> dont buy beer but buy the pump. its a rubber diaphram and they fail. if your lucky it will run very poorly when it does if your not it has been known to cause piston failures. do it once do it right and you wont need your tow boat US insrance.<br /> you did buy that as well didnt you?<br /> next time fix the basics before adding electroinics.<br /> good luck and keep posting

 

[laeelin]

Re: Yamaha 85hp outboard Carb problem...

<br />just replace the pump<br />dont buy beer but buy the pump. its a rubber diaphram and they fail. <br />

We checked it. <br /><br />Like 10 hours total use, and it still is working perfectly... <br /><br />It's not like the pump is so complicated that we cant figure out how it works.<br /><br />there is no need to replace it at this time that I can see.<br /><br />

<br />if your lucky it will run very poorly when it does if your not it has been known to cause piston failures. <br />

After spending 2 hours removing, cleaning, and rebuilding the carbs, it's purring like a kitten.<br /><br />

<br />do it once do it right and you wont need your tow boat US insrance.<br />you did buy that as well didnt you?<br />

The boat is insured.<br /><br /><br />

<br />next time fix the basics before adding electroinics.<br />

When the idea is to go offshore I'm not going without the electronics... For inshore a paddle works well enough if you have no other choice.<br /><br />Boat purring like a kitten or not.<br /><br />BTW: Thanks for the friendly advice... at least to the person that gave friendly advice.

 

[rodbolt]

Re: Yamaha 85hp outboard Carb problem...

hello<br /> it is friendly advice. I deal with blown motors almost daily. not a week goes by that I dont have to tell someone that the power head is toast. 90%of them due to customer neglect and not dealing with problems as required. you would not believe the stories. that is why I say do it now before it dies. its less than 40 dollars and the kit is even cheaper if you have spare time.<br /> that is what I tell them about water pumps as well. the price of the pump job remains the same wheather you rebuild the power head with it or not. keep it cool,fueled and oiled and its almost impossible to wear a two stroke out. I have a crabber now that has just a tad over 13 thousand gallons of fuel run through a 140 looper I rebuilt in 1998. the carbs have not been off since I did it. I change his filters often and the pump and t-stats at least once per year. so the advice is friendly I have been working on outboards almost 20 years. I have seen about any problems you wish to ask about. I have owned my own repair shop since 94. I also contract with several marinas in the area. I have wrenched for porshe,mazda,chevrolet oldsmobile I am certified in mercruiser,merc,mariner,force, suzuki yamaha and worked at a evinrude dealer for a long time. so yes I may know just a tad about what makes a two stoke quit. it ovver 20 years of wrenching I have seen thousands of blown two strokes. I have actually seen two that just wore out.<br /> good luck and keep posting

 

[rodbolt]

Re: Yamaha 85hp outboard Carb problem...

ohh and the 140 is still a VRO motor and gets a staedy diet of tech 2000 oil from wally world