[Diggler]

My Yamaha 115 4 stroke which only has about 50 hrs on it will not fire, Things I have checked, plenty of fuel, no water in seperator, checked all fuses, kill switch in,plenty of juice to crank just will not fire!! I noticed the last few times i started the motor it would hesitate before firing, and sometimes while running at low rpm's I could hear what sounded like a belt squeaking off and on. any suggestions would be appreciated, my guess is fuel pump? Motor is still under warranty but I may have overlooked somthing simple?

 

[john ronayne]

I have the same engine with the same problems. At 150 hours it would barely run. spent a month in shop until as last resort they pulled and cleaned fuel injectors. Injectors were firing enough fuel that it did not trip the flag on the diagnostic machine. Wasted alot of time replacing fuel line to tank, instaling water/fuel separator. Had same prolem again 2 weeks ago, went back to dealer and was told to use "ring free" a fuel additive by yamaha. Was also told to use this with every tank.. did the shock treatment, and it fixed the problem. I still have the intermittent squeak you mentioned, sounds like a belt. Not impressed with the engine, except for the fuel efficiency. Good luck.

 

[mike11]

same engine, same intermittent "belt" noise. 28 hrs. on engine, noticed the sound after about 24 hrs. which was just after getting the required 20 hr. warranty service done - I guess I should be relieved it's not something they did, which I've been suspecting. The only thing that came to mind that could sound like that is the impeller but it definitely seems to be coming from the engine. have either of you investigated it any further ?

John, how common and/or easy is ring free to find & would you recommend I start using it immediately ?
Diggler, are you back up & running & if so, what was the problem ?

 

[john ronayne]

I got the ring free at Sealing Marine in Grasonville MD. I imagine any authorized Yamaha service center should carry it. Based on what I was told, I would start using it immediately.

 

[mercurytech]

Your problem is clogged fuel injector. This is a common problem on the 115. Merc and Yamaha. As far has cleaning the injector... not going to happen, they need to be replace. The injector is a non-serviceable item and must be replaced. After they are replaced you should install a water separting fuel filter that is rated for 10 microns. The clogging is coming from carbon from the fuel pump brushes on the 2003 and older product and most likely bad fuel or contamination in the fuel system.

 

[john ronayne]

Injector can be cleaned, that is the soluction Yahama prescribes. I stood next to the tech as he removed the injector, cleaned it, blew it out with air, and reinstalled it. That corrected the problem.

 

[mercurytech]

Really... Last time I talked to Anthony (the Yamaha service rep) he said they were a replacement unit. Also if you have access to the yamaha 2005 marine technical guide, on page 2-56 it states" The injectors have unservicable screens in their inlets." I hope you didn't pay for your tech to be lazy and not correct your problem but put a band aid on it.

 

[WildeOne]

Diggler, no reason for you to be screwing with an engine that's in warranty. Take it to a dealer.

 

[john ronayne]

thanks for the advice mercury tech, Ill check that out.

 

[rwmanahan]

I have an 80 hp Yamaha with the same squeal in the motor. I've been putting belt dressing on the belt without much success. My dealer said there's nothing wrong with motor,just a squeeky belt. Just curious if you guys have a rattling noise in the lower unit when idling in gear. Dealer also said Yamaha has a little noise in there lower units. I'm not sure what to believe, mine sounds like everything is loose inside and beating together. I'm thinking about calling Yamaha to see if they will help me out.

 

[mercurytech]

Alot of times the sound of the air going throught the air silencer sounds like a squeal. Has for your gearcase your dealer is not being honest. If you can hear gear rattle there is something wrong. On some of the yamaha/ merc engines (115 four stroke) they need a special insert in the prop. I would check your gear lube, and also pull on the prop shaft and see how much play you have fore and aft and also side to side. Then put it in gear and see if everything still feels the same. Yuor gearcase should sound smooth except when shifting, then you will hear it when the clutches grab and also if you freewheel the prop you will hear noise.

 

[Diggler]

Tri-State found nothing mechanicaly wrong with the motor, they said it was vapor lock. Well that crossed my mind at the time of the problem and I let the motor set for a while and when that didnt work primed the bulb a few times and repeated the waiting game /priming process, no luck.It was not a hot evening when the problem occured either so the heat wasent a contributing factor.Any suggestions on what to do under same circumstances if it occures again? Tri-State said keep pumping the primer bulb, which didnt work the first time!

 

[WildeOne]

Vapor lock??? I don't think so. I would find another dealer. I've never encountered vapor lock on any OB and I've run engines in the SW deserts, with the air temp approaching 100° F. "Vapor Lock" requires fuel to boil in the fuel line or carb, and neither get hot enough for that to happen, unless your motor is ready to fry from overheating.

 

[mercurytech]

What year is your engine. I don't know about yamaha but merc had this problem on the smaller four strokes and had a recall for a fuel cooler to be installed. Not really hard to do just a little time consuming. Look at the fuel line coming into the engine. On the port side of the engine in the rear there should be a fuel cooler installed (long and recatanglar with 2 hoses on it) If it is on there then I would rule out vapor lock. (Unless you are running winter blend gas) Call the yamaha help line and tell them your unhappy with what the dealer told you and want Anthony to come out and looke at it. See what they say. Can't hurt but I still think you might have a bad injector.

 

[Butthead]

I have a 2005 115 yamaha 4 stroke, and love this motor. I have never (knock on wood) had it so much as belch much less have any problems.

This ring free you guys speak of, is it something that goes in every tank of gas, or is it a once a year deal. Also, I have about 100 hours on the motor already...Is it too late to start using it? What is the benefit of it?

 

[Diggler]

Mercurytech: I dont really go for the vaporlock theory myself because as I stated to service rep at Tri-state I noticed the motor was taking longer to fire the prior two or three trips out before it just quit on me. They say nothing mechanicaly wrong and I mentioned clogged injector and they said that was not the problem?What could they have done to get rid of this so called vaporlock that I didnt do? By the way its a 2005.