Yam F80, water in gas?

[andymach23]

Hi

I am in the process of buying a boat with a 1998 F80. I did a sea trial a couple of weeks ago and the engine ran great.

The surveyor has tried to run the boat a few days ago and the motor died after 5 minutes. Apparently here was alot of water in the locker where the fuel tank is, due to rain, and he thinks the fuel may have got contaminated through the vent. There is no external filter present.

A Yamaha engineer at the marina has apparently been looking at it and had the motor running on the hose but is 'not happy with it' and is to work at it again tomorrow.

If the gas has been contaminated with water is it a big deal to clear it out? I am worried that there may be another issue if it is taking a long time to fix. If it is up and running but not running well, could this still be a water in fuel issue?

How likely is it for significant amounts of water to get into the plastic tank passed the air vent? I think the water was sloshing around over the tank, and the tank was less than 1/2 full so would have floated maybe.

I have paid my 10% deposit and am due to travel to collect the boat when I get the report that the issue is sorted. I was thinking of running the engine on the hose to confirm that all is well before I pay.

Should I get the boat craned back in and do another sea trail to ensure all is well with the engine under load?

Sorry the detail is sketchy as I wasn't there when this happened. I will be getting more detail tomorrow.

Thanks

Andy

 

[andymach23]

Re: Yam F80, water in gas?

I phoned Yamaha UK and asked about this. I was told that the best thing to do is to change the oil and run the motor up to temperature, basically get it very hot, and there is a good chance that this would sort everything out.

I was also told that it is difficult for any water to make it into the plastic tank past the vent.

Maybe there is something else going on. Bad gas, dirt in the tank? Hopefully I'll get some news on it today.

 

[BruceAML]

Re: Yam F80, water in gas?

If I were in your position I would want to see and examine the work order for the motor. I would examine that closely and if it met my standards I would definitely test the motor in the water. A test in a barrel is not conclusive. If possible, I would contact the previous owner so that I could know the history of the engine. I would also call Yamaha UK with the model and serial number in order to find out the warranty history of the motor. Is this purchase from an individual or a dealer?

 

[andymach23]

Re: Yam F80, water in gas?

The boat is being bought off a private individual through a broker. The motor has been serviced in the last few years by the shop that is now checking over the motor.

I did a sea trial a few weeks ago and the motor ran perfectly. This happend when the surveyor tried to run the motor.

I am a bit sceptical about water getting in through the vent. The gas may be old but I'm thinking it ran fine previously.

I am waiting to get a report from the merchanic when he has finished. If all sounds ok, I will travel to the boat with a view to getting another trial to make sure the engine is ok. I'll be taking my own fuel tank with fresh fuel also. If it isn't working properly I'll likely be walking away.

If I take this home my local Yamaha shop will just throw parts at it in the hope of sorting it out.

The boat is in superb condition and is hard to come by so I hope it works out.

Does anyone have experience of dealing with water in fuel?

 

[BruceAML]

Re: Yam F80, water in gas?

Does this motor have an external plastic fuel tank? Is it a Yamaha brand tank? If the vent is closed on an external tank there should not be any water intrusion from an outside source. Of course, there is always the possibility of contaminated fuel or the engine can be "making oil" due to the wrong prop or a number of other reasons. Did you find out exactly what the repair shop is doing? What parts have been changed? Did you call up Yamaha and find out if there was any previous warranty work? Have you asked if the owner would sell the boat minus the motor?

 

[Woodnaut]

Re: Yam F80, water in gas?

Andy, I have had some experience with water in fuel. I have a 2006 90 HP 4-stroke Yamaha, but it is fuel injected. Is the 1998 F80 fuel injected or carbureted?

 

[andymach23]

Re: Yam F80, water in gas?

Woodnaut

It's carbs.

The broker has told me that the tech has had the carbs off to clean, the after re-installing the motor is running but is rough, like it isn't firing on 1 cylinder.

He is to try again tomorrow. The Broker says the tech has told him that there wouldn't be any chance of serious damage with a water (rain) in fuel episode.
I would rather make my own mind up on that score!

What is the absolute worst scenario with water in fuel and how much would it be to sort out?

If I walk away from this boat it will cost me approx $1600 in survey fees, flights, road travel etc to go and look at another. This would buy alot of remedial work!

The boat is in fantastic condition and hard to come by. I negotiated a good price and all was set before this happened.

There is no scope to buy the boat only.

I will speak to the surveyor tomorrow who ran the engine when this happened to get a better idea of what actually went on.

Thanks for all the replies so far!

 

[foxden]

Re: Yam F80, water in gas?

You've had a broker, a technician and a surveyor involved in this potential purchase. What makes you think that advice from anonymous folks on a forum who haven't seen the boat or motor are going to guide you in this financial decision?

 

[andymach23]

Re: Yam F80, water in gas?

The advice available on this forum is fantastic and much appreciated. I do not have acess to Yamaha Mastertechs locally in the UK. There are many hugely experienced people who go out of their way to help out here.

This forum has helped me immensely over the years.

I will decide how to proceed based on info from all available sources.

This post is about getting some technical input into issues involving a 4 stroke motor stalling after getting water in the fuel. A common enough scenario maybe?

 

[BruceAML]

Re: Yam F80, water in gas?

This message is for Foxden. You have tried to insult the many people who post on this forum by calling us "anonymous folks". We are not anonymous as we have all had to register in order to post on this forum. I have often seen Rodbolt explain and provide correction for a problem even though he has not seen the boat and motor. He is usually more skilled at this than people who have seen the motor. You owe us an apology.

 

[lasvegaskid]

Re: Yam F80, water in gas?

The advice available on this forum is fantastic and much appreciated. I do not have acess to Yamaha Mastertechs locally in the UK. There are many hugely experienced people who go out of their way to help out here.

This forum has helped me immensely over the years.

I will decide how to proceed based on info from all available sources.

This post is about getting some technical input into issues involving a 4 stroke motor stalling after getting water in the fuel. A common enough scenario maybe?

Once you dump the fuel, you might try to put some water absorb in the new fuel. You should be able to get it at the marine supply store. I have used it, and it worked great. Also do you have a water separator filter in your fuel line?

 

[andymach23]

Re: Yam F80, water in gas?

BruceAML

I agree, time and time again Rodbolt cuts through the B.S.
Hopefully if he is around he can give some input on this.


Lasvegaskid

That's not a bad idea on the water absorb for the fuel. I put some 'conditioner' in my own tank for my F40 recently. I'll have a look at it. The boat has no fuel water separator, unfortunately, but will have one if I get the boat.

In any case, if I get as far as another sea trial I will be bringing my own gas tank, with good fuel in it.

Cheers

Andy

 

[rodbolt]

Re: Yam F80, water in gas?

sorry for the delay, I was at the F350 school in Kennasaw GA.
DO NOT use water sorb. you will fight water in the carbs for a long long time if you do.
pump the tank,dry it out,usually through the fuel sender hole.
clean and carefully flush all engine fuel lines and carbs. the passages on the F80 are very small.
some have brass plugs over the idle mixture screws that must be removed to clear water.
the linkage MUST be reset with a tech mate vacumte or equivalent manometer. ya just cant guess.
have a 10 micron(yamaha makes a good one) water fuel seperator installed. yamaha also makes a model with a drainable fuel bowl that can be checked daily for water.
MAKE sure the engine is running correctly BEFORE you buy it.
monday I leave for VE so I may or may not be around after that.

 

[foxden]

Re: Yam F80, water in gas?

I apologize if I offended anyone on the forum. I have garnered valid information and advice on repairs myself. My point was directed at making a purchase where I subscribe to "do all the worrying before you place the bet."

 

[andymach23]

Re: Yam F80, water in gas?

Thanks Rodbolt.

I spoke to the surveyor today. He says that when he arrived to test the boat the plastic tank that was connected up to the F80 (year 2000 model, not 1998 I discovered today), was actually under water in the locker. The air vent was open so a significant amount of water must have got into the tank.

He primed the bulb and ran the motor for a few minutes before it stopped and would not restart. Presumably it ran initially on the good fuel in the carbs then died when the water came through.

The obvious question is why he ran the motor at all when the tank was submerged and the vent was open. Maybe the priming bulb was outside the locker? Who knows!

He says that when he took the fuel line off the engine water ran out.

This now happened a week ago. If it takes another couple of weeks to get the water cleared will it cause any more lasting damage lying in there?

What are the chances of anything major being damaged? Could water be rusting the pistons or the valve gear etc.

The tech guy at Yamaha UK stressed the importance of changing the oil and watching for emulsification. I take it from this that there is a chance that water can make it past the carbs and start messing things up big time?

Cheers

Andy

 

[rodbolt]

Re: Yam F80, water in gas?

most the time, once water gets in the carbs the engine quits long long before it can get past the rings and to the crankcase.
however enough can get past the carb to rust valve stems and seats as well as cylinder walls.
I dunno why folks do stupid things but they do.
your F80 can be retro-fitted with a water detect filter that will sound an alarm if the cup gets water in it.

 

[andymach23]

Re: Yam F80, water in gas?

Rodbolt

From what you say, it looks like the engine will be ok if a proper clean out of the carbs is done. It all depends then how diligent the tech is.

If I get word that the motor is 'fixed', I will make sure I get a sea trial, to make sure everything is in order before I tow the boat home.

I will also fit a water/fuel separator and avoid any water sorb.

I appreciate the quality advice!

Enjoy your trip.

Andy