Mercruiser 5.0 LX, stalled out and will not start

Julians

Cadet
Joined
Sep 9, 2012
Messages
12
Greetings,

I recently purchased a 1994 21' wellcraft eclipse SE. The engine ran great the first few outings both at low and wide open (although it was a little hard starting). On the fourth outing she stalled out and i could not restart it.

It does crank and some times runs for a few seconds then shuts down.

Suspecting fuel problems cause i was at about 1/4 tank when she stalled, I replaced all the filters, fuel pump and siphoned out about 5 gallons from the bottom of the tank thru the fuel sending unit and then added about 10 gallons of fresh fuel.

It Still does not start, I DID Notice however that the 4 barrel carb ( which i think is a rochester) seems to be leaking onto the intake manifold from both sides of the carb. An ideas or suggestions?

Thanks Jules
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: Mercruiser 5.0 LX, stalled out and will not start

Do you have spark? Are the plugs wet with fuel? water?

If you pour some gas into the carb will it start? Did you check the filter to see what was in it before replacing it? Engine won't run if the carb is full of water.
 

Julians

Cadet
Joined
Sep 9, 2012
Messages
12
Re: Mercruiser 5.0 LX, stalled out and will not start

I do have spark...the engine did start but cut out shorly after. Unfortunatly i did not thouroughly check the contents of the old filter. I did not pull any plugs yet either. How do you check for water content in the fuel? How can you tell water from fuel by looking at the plugs?

Thanks Jules
 

dingdongs

Chief Petty Officer
Joined
May 29, 2009
Messages
649
Re: Mercruiser 5.0 LX, stalled out and will not start

fuel should not be getting on the external parts of the manifold.big fire risk.empty contents of your fuel filter into a bowl and check for water droplets.then replace filter with new one.remove distributer cap and see if theres any moisture.if anything looks rough or green inside replace that too.as stated above is there a good spark and when were the plugs all checked.pictures may help and compression check may be able to tell us what the engines internal condition is.
 

littlebookworm

Chief Petty Officer
Joined
Nov 30, 2007
Messages
574
Re: Mercruiser 5.0 LX, stalled out and will not start

Start with the advice you've been given; namely, a full tune-up (plugs, wires, cap, rotor). Check the fuel, as indicated. You can pour the contents of the filter into an empty glass jar and let it sit a while. Any water will separate from the fuel. If there's water present, you may need to drain and clean the tank. My gut feeling is that the no-start is being caused by the need for a tune-up and a carb overhaul. If she still doesn't start, it's time to check the carb. Fuel leaking out is bad and dangerous. You may have a sticky float. Overhauling a Rochester 4-barrel isn't that difficult, but it is a little complicated. If you haven't done one, you could have a mechanic overhaul it for you. Any qualified auto or marine mechanic can overhaul a carb. Good luck and let us know the outcome. Hy
 

Julians

Cadet
Joined
Sep 9, 2012
Messages
12
Re: Mercruiser 5.0 LX, stalled out and will not start

Thanks guys! Will first check the filter contents as well as the ignition: check for spark, as well as the condition of the plugs, cap and rotor.
Sounds like i need to rebuild the Carb also....do you know if it is a Rochester 4 barrel carb on my 5.0LX mercruiser? And where can i buy a reliable rebuilt without paying too much? Is it hard to rebuild myself?
I see a bunch of rebuilt carb sources online including ebay and amazon, any sugestions
Thanks again
Jules
 
Top