1999 150 EFI Intermittent Stalling

[GlasV162]

Hello,

Today our '99 Merc 150 EFI developed an intermittent stalling problem, both traveling at idle and up to about 3000 rpm. It would stall, but then would start right up again on the 1st turn of the key. It also takes about 3 turns of the key to start when warmed up, then it idles great--until the intermittent stalling problem. Any thoughts??
Thanks,
John

 

[Paul DuLaney]

Re: 1999 150 EFI Intermittent Stalling

When was the last time the fuel filter was replaced and the fuel pump rebuilt. The fuel you gert along with the alcohol in it can mess a motor in no time . I use a additive in mine Starbrite that remover the moisture along with the alcohol.

 

[Coloradolakeboy]

Re: 1999 150 EFI Intermittent Stalling

Take a look at CDI's website. There is some info about missing and problems occuring at 3000 rpm. Look at the index, but it's around page 82-83.
http://issuu.com/cdielectronics/doc...t.xml&backgroundColor=000000&showFlipBtn=true

 

[GlasV162]

Re: 1999 150 EFI Intermittent Stalling

Do fuel pumps slowly fade or die quickly? It's been my experience with cars that fuel pumps quit rapidly with no warning--are outboards different?
Thanks,
John

 

[GlasV162]

Re: 1999 150 EFI Intermittent Stalling

Hi again,
Will hooking this motor up to the shop computer help diagnose the problem?
Thanks
John

 

[GlasV162]

Re: 1999 150 EFI Intermittent Stalling

Hi,
We picked the boat up from the shop a week ago, after a $1,000.00 fuel injector cleaning job. The motor ran for a few hours, showing the same symptoms of intermittent stalling, but this time it finally completely died. I checked the fuel filters for water, and there was none. I then noticed a fuel leak coming from the top of the motor, in behind the oil injection reservoir. Needless to say, after finding this, I didn't try to start it again. Any tips?? Thanks,
John

 

[GlasV162]

Re: 1999 150 EFI Intermittent Stalling

Hi again,

After bringing the boat back to the shop, they discovered a piece of fuel line had broken off and caused a float to stick open in the VST, which they said was causing the fuel leak. They fixed that, but we still have the same stalling problem. It will go along fine, at all RPM ranges, and then all of a sudden it will stall. If anyone has any advice, I'd really appreciate it. Needless to say, after spending over $1,000.00 and still having the same symptoms, we're getting frustrated. Thanks.

 

[GlasV162]

Re: 1999 150 EFI Intermittent Stalling

Hello again,
Today we tried running on a portable tank in hopes of ruling out an issue w/ the built-in tank. Same symptoms. Any thoughts??
Thanks,
John

 

[Faztbullet]

Re: 1999 150 EFI Intermittent Stalling

We picked the boat up from the shop a week ago, after a $1,000.00 fuel injector cleaning job

Gee-sh they seen you a coming. It only cost about $190 to have a set(6) of these cleaned,new filters installed and flow balanced and you get a flow sheet to see what was done thru Brucato. When it stall is the fuel pump still running? If not the driver board in the ECU may be going bad. If the mechanical pump diaphragm has not been replaced do that first. To check ECU driver remove cowling and test run it on trailer to see if problem will occur, if it does remove the ground wire off the fuel pump and install a jumper wire from the pump - terminal to a good ground as this bypasses ECU driver. Also if the engine is overcharging it will cause the ECU to act weird....

 

[GlasV162]

Re: 1999 150 EFI Intermittent Stalling

Hello,
I took the boat to our mechanic 2 weeks ago; today they told me they took it to the lake and were unable to duplicate the problem; it ran fine--no stalling at all. The one thing they did differently was to run it with a "test wheel." I asked the tech what that was, and he said it's a special prop that's used for diagnostic purposes so they can get the motor to run all the way up to its max. RPM of 5600. He said it ran great at all rpms with no stalling. With the prop I normally run, I can only get it to run up to 5200 with the trim all the way out. At this point they're too busy with winterizations to do any further troubleshooting on my boat; could changing the prop cure the stalling problem??
Thanks,
John