Mercruiser 3.0 LX persistent problems

[CPro]

I've got a 97 SeaPro 190 WA with a Mercruiser 3.0LX. The first year we had the boat (we've had it for about 4 years now), it ran like a champ. Every year since, I've had really bad luck with it. I've rebuilt the carburetor, replaced a lot of the ignition system components (plugs, wires, distributor), had the fuel cleaned by a fuel truck, replaced the fuel pump, and have recently verified the timing and choke settings. The main problem is symptomatic of fuel system problems in that my fuel filters get gunked up pretty quickly with small particles. Usually, if I swap filters out things improve for a trip or two..and then it's time for new filters. I've also installed an inline fuel filter/water separator.

Is there anything else that could be "off" that could make the engine more sensitive to a clogged filter?

From my last carburetor rebuild, I'm not 100% positive that the gasket sealing the venturi cluster is perfect. For some reason, the rebuild kit didn't have a new one this time and I tried to reuse the old one.

Thanks in advance for any advice you might have - it's been a frustrating few years here recently, as you can imagine!

 

[dingdongs]

Re: Mercruiser 3.0 LX persistent problems

most are yearly service items but your tank needs totally emptying and flushing all the crap out.once this is done boating should be more enjoyable.you could always try a portable plastic tank just to prove a point.

 

[dubs283]

Re: Mercruiser 3.0 LX persistent problems

take a peek inside the fuel tank itself

remove the fuel sender assy and shine a light inside, any chunkys in there??

also may want to remove and inspect the pick up tube in the fuel tank, check for debris/blockage

the small particles may be corn, are you using non-oxy fuel or just plain old 87 octane pump fuel?

 

[EddiePetty]

Re: Mercruiser 3.0 LX persistent problems

.....in addition to verifying that your tank is clean, check your fuel vent. If the screen(s) are missing or damaged, mud dabbers could be getting in there, road grit during transit or trash thrown up by the lawn mower...it happens!!!!

 

[CPro]

Re: Mercruiser 3.0 LX persistent problems

Do you mean there could literally be pieces of corn in there?? I'm using regular old 87 octane from the gas station. I'll definitely shine a light in there and see how it looks...and I'll check the vent as well.

Thanks guys,
Trev

 

[fishrdan]

Re: Mercruiser 3.0 LX persistent problems

The main problem is symptomatic of fuel system problems in that my fuel filters get gunked up pretty quickly with small particles.

Sounds like you have identified the problem. How hard is it to remove the tank, so you can clean it out?

With a new water separating fuel filter in place, I would just run it and see how it reacts. Keeping a spare filter on the boat in case it needs to be swapped out on the fly. The dinky stock fuel filters will clog easily with junk in the tank, while that huge add-on filter will take a lot longer to clog.

This suggestion is probably only a band-aid. But, hook up a cheap universal electric fuel pump to the water separating fuel filters output, then from the output of the pump run some fuel hose back to the tank's fuel fill. Basically, cycle the fuel through the filter a bunch of times to help clean it up. Probably a good idea to drive the boat around (truck & trailer) during the process so the sediment in the bottom of the tank gets sloshed around and suspended in the fuel, do this with 1/2 tank or less of fuel so the sediment will be concentrated in less fuel. The universal electric fuel pump I have is pretty slow, probably 30-40 GPH, it takes a long time to fill a 5 gallon jug.

Best thing would be to remove and clean the tank.