fuel problems

[dmscrown]

Hello gents, heres the back story:

Just bought a 95 202BR with the merc 5.7mag/alpha 1, the person i bought it from said it sat for a year. I decided to purcahse it, was a hell of a deal i though. The person i bought it from said they took it to a boat place, they checked it out, checked the fluids, ect..

Filled it full of gas (87oct), got to the lake, dropped it in the water, started up great, idled fine... then she ran awesome!!! 50+ mph for like the first half hour, then the engine started cutting out, rpms would drop, then it would eventually die... BUT if you let it sit for like 20 minutes or so, it would start up fine again, run great... 20 minutes later, slowly peter out again and die... sit and wait, start up, would go good, then die again, rinse and repeat.

Now to me, i relate everything to how cars run, (thats what i know) ive had the same situation with vehilces, and it 9/10 times it was the fuel filter. After i got it home, i poped it off, dumped it out, but it didnt look dirty, i know the dirt is on the outside of the filter element, and that you dont dump out the crap, it stays in the filter usually.

So now my plan is to go to a boat place, and get a couple of filters. Now assuming there was at least a gallon or so of "old gas" still left in the boat from the year long storage. Pop a new one on, run it.. see what happens, have another for back up...

1. Is there anything else you guys think i should check before going back out?

2. High octane or regular gas.. 93/87?

Any thoughts/opinions?

thanks in advance

 

[QC]

Re: fuel problems

So now my plan is to go to a boat place, and get a couple of filters. Now assuming there was at least a gallon or so of "old gas" still left in the boat from the year long storage. Pop a new one on, run it.. see what happens, have another for back up...

Good plan, but might not the problem although it is possible . . .

1. Is there anything else you guys think i should check before going back out?

Check your fuel tank vent, and maybe bring a separate source of fuel to see if she'll run from a different tank. May be something in the tank, but this one sounds a lot like a clogged vent line . . .

2. High octane or regular gas.. 93/87

87 is probably fine, I don't run premium unless the ambient temp is above 100 and then I start with my internal debate

 

[dmscrown]

Re: fuel problems

Check your fuel tank vent, and maybe bring a separate source of fuel to see if she'll run from a different tank. May be something in the tank, but this one sounds a lot like a clogged vent line . . .

Fuel tank vent? is that the vent thats next to gas cap? cuz gas squirted out of it when i was filling it up.. haha

are their other vent lines? so i assume there isnt a vacum line running from the tank to the carb? like vapor line?

 

[smarks]

Re: fuel problems

If you had gas squirting out the vent line your probably ok there. Posibbly a fuel pick up problem or the sighpon valve they put in line there
Steve

 

[cr2k]

Re: fuel problems

Other possibility is a coil going bad, heating up and breaking down.

 

[Don S]

Re: fuel problems

Here are some tests you can do to check the fuel system.

http://forums.iboats.com/showthread.php?t=283269

When the engine does die, two checks to make.
1. Check for spark
2. Pump the throttle and see if gas squirts out of the accelerator pump jets.

 

[bruceb58]

Re: fuel problems

Other possibility is a coil going bad, heating up and breaking down.

99% of the time it is not the coil. There are probably thousands of good coils in people's spare parts bins out there because of this.

 

[dmscrown]

Re: fuel problems

Well...... it doesnt seem to be a fuel problem

We drained all the fuel back out, took the fuel sender out, looked around the inside of the tank... looks to be pretty clean.

took all the lines off, flushed them

replaced the fuel/water filter

put about 10 gallons of 90 octain, and some mercury engine treatment...

same thing, ran great for 20 minutes, started cutting out... changed the fiter again (on the water), same thing, seems like no change... ran for a few minutes... then died..

other ideas?

 

[Alpheus]

Re: fuel problems

run it off of a remote tank and see if problem persists. make sure your choke is working correctly.

 

[dmscrown]

Re: fuel problems

run it off of a remote tank and see if problem persists. make sure your choke is working correctly.

+

did that... same effect... pretty sure its not the tank or the lines, or system.

what would make the choke mess up after the engine was warm? and not mess up the whole time? i mean it runs great for like at least half an hour

 

[Rscardina]

Re: fuel problems

I used to have a similar engine..mine was the 3.o.. I think the design was pretty much the same..

I had some things happening in my carbs, although i never found out exactly what it was I ended up rebuilding and everything cleared up..

I was able to deduce this by taking the flame arrestor off and when it started to idleel down and want to die i sprayed starter fluid down and she kept running.. I knew at that point my feul delivery was being impeded..

Not sure if this is what your getting or if you proved fuel is getting to the carbs but I suspected sticking needles or floats..so i bit the bullet and just did a rebuild on the carbs.

I'm sure someone here will give you better ideas than mine since I am no expert, just good at troubleshooting..

 

[lonemust]

Re: fuel problems

My 140 was doing the same thing Memoria lweekend at the house. After it had run for about 45 min on the muffs. It died let it set for alittle while and it started back up but ran crappy. I checked and rechecked everything. And I mean everything. Bat, ign, fuel, even starter. When I tested the coil to begin with it checked o.k.. After about two hour I gave up for the night. Next morning checked everything again. Coil showed good. Fired it up ran fine for about 1/2 hr then puked out. Cheched the coil right after it died and the coil showed bad. So put a new coil in it and it fired right up and haven't had a problem sense. So I my obinion CHANGE the coil and see what happens. You have already went though the fuel system (except rebuilding the carb) so I say change the coil.

 

[dmscrown]

Re: fuel problems

well.. looks like im going to try a new coil...

let ya know how that goes.

 

[bruceb58]

Re: fuel problems

So when it dies, do you immediately check for spark like Don suggested?

 

[lonemust]

Re: fuel problems

I would and did when mine did that. That's how I found the coil. It had spark just very weak, would not light spark tester but would spark holding less than 1/8' from side of block.

 

[smarks]

Re: fuel problems

Was the coil hot to the touch?

Steve

 

[bruceb58]

Re: fuel problems

I would and did when mine did that. That's how I found the coil. It had spark just very weak, would not light spark tester but would spark holding less than 1/8' from side of block.

That question was for the OP.

 

[dmscrown]

Re: fuel problems

That question was for the OP.

I have no idea how good the spark is...i got the S*&t shocked out of me once trying to play with coils and stuff, so now i wont mess with them.

im just going to take it to the fix it place

 

[dmscrown]

Re: fuel problems

ok well the fix it place is booked till middle of july...

i got the cap off, the sensor wheel out, and the pick up sensor out.
the cap and the little sensor thing has some corosioin on it, prolly just order new ones.

How the H do you get the module off the back of the distrubuiter..???
im too big a guy to climb back behind the engine, is it held on by screws? or what? i can feel the wire connector, but i cant figure out how to make it come out.

 

[dmscrown]

Re: fuel problems

re thermo greased the ign module,
new coil
new magnetic sensor in the dist
cleand up the contacts in the dist

runs like a champ...

thanks for the help everyone