Mercruiser 5.0L EFI Fire Problem

[FabienLamour]

Purchased used boat last year, engine was running ok. I replaced sparks, wires, distributor cap and rotor. Engine does not run good since. It cuts of every 2 seconds and drops 1000 RPM each time. I checked wire sequence, all appear good. Help please...

 

[thumpar]

Do you have a serial number or at least year and what drive? When it cuts out does it die completely or just drop 1000rpm and keep going?

 

[FabienLamour]

If the RPM is at 3000 or 2000 it does not die completly, it drops by 1000 RPm but keeps Going. If it is idling around 1000 then it dies.

 

[FabienLamour]

It is on a Crownline 21SS, 2007. Boat serial is Jtc69729dxxx

 

[Bondo]

Ayuh,..... Welcome Aboard,...... We don't care 'bout what yer boat is in this forum,.....

We care only 'bout yer motor, it's serial number, 'n the drive mounted behind it,....

 

[FabienLamour]

It is a 2007 Mercruiser 5.0L (Serial 0W8953xx) with Alpha (Serial 0W68977xx).

I have replaced the spark plugs with high performance NGK, new spark wires (Sierra), distributor cap and rotor (Sierra).

It started to cut off ever since this tune up.

I was told it could be my timing that would now be off as a result of the cap and rotor replacement.

What do you think?

 

[Maclin]

• Cap and rotor not correct or installed incorrectly
• Spark plug wires out of order
• Spark plug gap or heat range or way off or incorrect spark plug specification
• Changing cap and rotor will not affect timing unless you moved/removed the distributor itself.

 

[FabienLamour]

Thanks a lot. I am taking it in to a shop tomorrow...

 

[Bondo]

It started to cut off ever since this tune up.

Oh, Ohhhh,..........

 

[FabienLamour]

Problem identified...it is first the Idle Speed Control Meter. But the mecanic came to realize that i have water in gas tank.

How am I suppose to eliminate water from the gas thank?

 

[thumpar]

Drain it. There should be a round access hole above the tank. That will allow you to get in and drain everything out.