Am I in for pain with a fuel injected motor....?

[scottfromoz]

Hi all.

I do not use my boat these days like I should/used to. I have a 93 Yammy 115 V4 that I love and it has been a gem. I wonder though how long she will last, particularly doing a lot of sitting around (corrosion on the inside of the galleys). I start her every 4 weeks and run her up to temp on the muffs for about 10 minutes. I use fuel stablizer and a good water seperator fuel filter - fine micron jobby. However sometimes I get caught out either with fuel a bit older than I thought or just fuel evaporation in the bowls causing varnishing/crap in the jets...then its a strip down and clean up and she runs like a dream again.

My worry is I 'upgrade' to a fuel injected motor (I fantasize of an F150 4 stroke) whether it be Yammy or Optimax etc is whether for me that is a bad move. If the fuel evaporates in the rails do you get injector blockages and then if so what is the process and cost of fixiing - assuming ultrasonic baths etc as a minimum and possible new injectors (!!!!)....and of course if I let the fuel go a bit off apart from the problem you can encounter, as with carbs of course, of poor fueling and timing problems from that, am I asking for injector problems etc.

I know that motors of any sort dont like sitting, but I guess I wonder whether I might be better going up to a 150/175 V6 Carbed Yamm new. I know the benefits of injected in terms of fuel efficiency, noise, response, cold start, idle etc and Im not asking about that cause for me and how little Im using the boat all that is not an issue and my 115 runs like a gem hot and starts like a bought one.

Cheers and thanks

PS. Thanks Rodbolt for continuing to be such a great help on this forum, if you read this.

 

[robert graham]

Re: Am I in for pain with a fuel injected motor....?

If you have water/ethanol/fuel/varnish problems with your carbed motor, then you'll have the same problems or worse with the fuel injected motor. Water in the injectors can really screw them up, often to the point of having to replace them at $100/each. Stabil Marine Fuel Stabilizer has worked very well for me and I use a bit heavier dosage for long lay-up periods. I also drain my carbs several times per year and believe it's time well-spent. This is just my experience, Good Luck!

 

[scottfromoz]

Re: Am I in for pain with a fuel injected motor....?

Thanks very much Robert. I run my carbs 'dry' by shutting off the fuel at the line when I am idleing her on the muffs...I figure cause the Yam injects oil at the reid valves im pretty safe in terms of keeping up lube in the pots until it stalls and has no load....any takers on that?

Cheers

PS. So yep it gets expensive for a 4 cyl 150 thats about 500 australian in parts just for the injectors...

 

[robert graham]

Re: Am I in for pain with a fuel injected motor....?

I don't think you can actually "run the carbs dry" like that because of the location of the jets. See if you can locate those drain plugs and if you can get to them with a wrench or screwdriver then I'm confident that's the best way to go. Go heavy on the Stabil Marine and you're probably O.K. anyway. My motor is a 90HP 3 cylinder 2 stroke and carbs are very easy to get to for draining, I understand carbs on some motors are hard to get at. Good Luck!

 

[Capt Ken]

Re: Am I in for pain with a fuel injected motor....?

We actually have very little fuel system problems with injected engines compared to carb'd engine. Fuel injected engine's fuel system is not open to the atmosphere thus no evaporation. Dirty fuel can cause problems with any engine but with the proper filter system, it shouldn't bother the engine. As for water, most fuel injected engines have a water sensor built into the engine fuel filter that will tell you if you are getting water.

 

[rodbolt]

Re: Am I in for pain with a fuel injected motor....?

yep, you simply CANNOT run a yamaha carb dry.
you can drain them but not run them dry.
every spring I get to claen the bowls on dry carbs.
most modern EFI and DFI motors for the past 3 years or so have a water detect function in the engine fuel filter.
like capt ken says modern EFI and DFI do not vent the vapor seperator directly to the atmosphere and the biggest issue is nasty fuel being introduced to the system.
still doesnt mean you can leave it sit a year and expect it to work.
my 175 E-TEC sits for months at a time as does my F150 with no issues, I do dispose of ALL gasoline over 3 months old in ALL my two strokes.

 

[mswalter2009]

Re: Am I in for pain with a fuel injected motor....?

every spring I get to claen the bowls on dry carbs.

Rodbolt, what do you mean here? Is it that boat owners think they are emptying the carb bowls by removing the fuel line when in fact they are not. Spring time comes and they have carb related issues. Per your and others advice I am not draining the carbs when the boat will sit for several weeks or more. Its easy on my 90 2strk.

 

[rodbolt]

Re: Am I in for pain with a fuel injected motor....?

exactly.
the idle fuel jet on most yamaha carbs sits about 3\4 of an inch or so above the bottom of the fuel bowl, the main jet very close to the bottom, ALL fuel goes through the main. as soon as the liquid level drops below the idle fuel jet,also called pilot fuel, then it quits leaving gasoline in the main and bowl that turns nasty with time.
if its going to sit more than 30 days I reccomend simply draining them.