2006 Twin F60s ran great. but not run for 6 months, will not start, fuel starved.

[jgraeber]

After a complete tune up, still not firing. Checked fuel lines OK. Inline fuel filters changed and receiving fuel.

[boscoe99]

Are you hearing either of the fuel pumps run when the key is first turned to the on position?

For two motors to suffer the exact same failure mode at the exact same time is very unusual.

[boscoe99]

Do you have a fuel pressure gauge? Are you seeing fuel pressure when the key is turned on?

Does the alarm system work? If the kill switch is on the motors won't start. But you should hear the warning horn if this is the case.

How do you know that it is fuel starved and not ignition system related?

[99yam40]

back in 2014 you posted about your 2009 F60s, are these 2006 F60s the same motors?

it would be best to always post the complete motor info so everyone knows what the motors are.

I am guessing they are fuel injected

[jgraeber]

Thank you boscoe99 and 99yam40 for your response. Yes these are the same 06 F60s and fuel injected. I do not have a fuel pressure gauge. The alarm system does work as far as I know. I don't know about a kill switch. I have the safety clasp below the key which must be in place or the motors will not start. I do not know for sure that it is fuel starved, its just the impression I get because starter is working. When these motors start, they start within a second or two. They always have, like any well tuned engine. They usually fire immediately. If it is the ignition system, I don't know but the starter is working.

Regarding hearing the fuel pumps, I've never heard them before. On my 23' boat, the motors are quite a ways back there so, I've never heard any kind of fuel pump sound. And you are right, for both motors to be exhibiting the same problem, it must be fuel related. I am thinking that I need to start at my fuel line with the ball and replace them both and work my way up the line. I am thinking that somehow I allowed dirty fuel to go up the line, maybe some gunk that was at the bottom of the tank found its way up the line. It is the only thing I can think of. In the past, I've run out of fuel as I was almost home from a long trip fishing. When I added new fuel, the motors would not run smoothly for a minute or two because of sucking up water/gunk from the bottom corner of the tank, evidently, then they would clear themselves out once the new fuel was ingested.

[jgraeber]

Also, both racor bowls are full of fuel, as well as the inline fuel filters so that should tell me that the fuel pump is working, other wise, there would be no fuel in the inline filter bowl. This is the first time when turning the ignition key, the motors have not started immediately. As I said, the starters crank hard and heavy as both batteries are fully charged, but there is no firing what so ever. Perplexed. Where could there be a blockage? Or could it be an ignition problem with both motors at the same time??

[TownsendsFJR1300]

Also, both racor bowls are full of fuel, as well as the inline fuel filters so that should tell me that the fuel pump is working, other wise, there would be no fuel in the inline filter bowl. This is the first time when turning the ignition key, the motors have not started immediately. As I said, the starters crank hard and heavy as both batteries are fully charged, but there is no firing what so ever. Perplexed. Where could there be a blockage? Or could it be an ignition problem with both motors at the same time??

You might try hooking your fuel line to a temp (6 gallon) fuel tank and simply bypass the inboard tank.

If it runs, you know there's an issue in the boats tank, line, pick up, etc..

As noted above, re fuel pump noise, have a helper turn the key on (not crank) while you have the cowl off and listen to the VST fuel pump.

I gather both engines have their fuel lines run to one fuel tank (currently), thru ONE pick up? (Common denominator)

[fairdeal]

Also, both racor bowls are full of fuel, as well as the inline fuel filters so that should tell me that the fuel pump is working, other wise, there would be no fuel in the inline filter bowl.

yes and no;
there are two fuel pumps, one mechanical, one electric, Boscoe is asking about the latter.

You should understand that your engines (as typical with fuel injected outboards)
have their own built-in miniature fuel tank; that's what they run off - its called the VST

The mechanical pump (and the primer bulb) serve to transfer fuel from the boat fuel tank,
to fill that VST.

Its the electric fuel pump, inside the VST, which supplies fuel to the injectors so that the engine runs.

If you pump the bulb until 'it gets hard' - that means you have successfully filled the VST completely.

And while you may have to take the cowling off to hear it,
when you first turn the key to 'on'
you should hear that electric fuel pump inside the VST buzz for a feew seconds,
as it pressurizes the injector fuel rail.

[rodbolt17]

never understood why someone would do a tune up on a broke motor????

[99yam40]

I would check to see if either motor is getting spark to the plugs before doing anything else.
sounds like you have one kill switch that kills spark to both motors.
maybe I am wrong and you have 2 key switches and 2 kill switches.

If they have spark, then check both motors for fuel pumps running at key on.
both electric pumps should have 12 volts to them when key is turned to the on position.
the individual motor ECUs then make the pumps run by grounding the negative side.

if you had water in the fuel and left them sitting with water in the VSTs there is a good chance the electric pumps have rusted up and will not turn

[jgraeber]

Thank you everyone for your ideas and suggestions. I did not know my motors had 2 fuel pumps and thank you for the education.

rodbolt17, the reason I did a complete tune up is because it was due and I was hoping by going through all those steps, I might discover where the problem was.

99yam40, what is the best way to check for spark, remove one plug cap and check visual? I will hook up my digital tester to the VSTs or ECUs to check voltage. I'm not sure exactly where the hook up is but I will find it. I do have 2 separate keys, ignitions and kill switches below each key.

One more question, I installed a new relay on the port side motor as the tilt had failed. The new relay did the trick, but it is much louder than the stbd tilt. Might I need to check the hydraulic level in the tilt? and where is the hydraulic fill for the tilt?

I will perform the tests you suggest and let you know what I find. As I am in Hawaii and I work all day, you won't hear back from me until this evening PST. There is a chance that water in the fuel sat in the VSTs and testing for the sound of the VST pump will tell. Thank you guys once again.

[walleye1]

Yamaha Service Manuals.pdf Work some over time and get one.

[jgraeber]

I was able to get to my boat between jobs and had my 86 yr old mom help me turn the key on. Pulled the cowels and listened for vst. I heard for the first time, a soft high pitch whine going to a higher pitch sound, as if the pump was running for about 2 seconds and then it was done. When I tried it again, there was no sound, obviously because the bowl was already full. I then tried the stbd motor with the same result. So I believe that both VSTs are doing their job.

I then pulled a plug on each motor and while cranking the motor with key in start, (full right) position, was able to detect a spark on both motors. This is as far as I got in tracking down the problem.

I am hoping that you kind and knowledgeable souls will advise me on the next steps I should take.

The extent of my knowledge is in performing tune ups, basic maintenance, changing fluids, props, impellers, running cables, steering, auto pilot, etc. I am not a yamaha motor mechanic, so I appreciate all your helpful hints, pointers and undeniable expertise. Thank you all once again.

[TownsendsFJR1300]

Seems the injectors are not opening, or no / little fuel pressure there.

Spraying a spritz of fuel down the throttle body, while cranking, would tell the tale. If it "fires off" (as it likely will), you've got it narrowed down.

I'd be checking the connection at the ECU for any corrosion, loose wires, etc- (which tells the injectors when to open, and their probably not)


*Why this is happening to both motors as the same time, is perhaps LOW BATTERY VOLTAGE? The engines need enough battery to operate the starter, ECU, injectors, etc. Depending on your configuration, your BATTERY(s) / ELECTRIC to the engines is also a common denominator...

[panasonic]

You should really do yourself a favor and get the proper service manual for your engines...as Walley already suggested.

When someone then gives advice or suggestions you can refer to the manual for wiring diagrams, systems break down, etc.