misskristy

I have a stock 330 gen iv. It has a blue msd system. I took it out for the first time this past sunday after a long winters rest. The boat runs great. I can cruise all day right up to 3800 even 4000, but when I put the stick down the engine winds up at about 4200 it acts as if it has run out of gas. The second I pull back on the stick all is well.

I put the boat away with a full tank and a foged motor. When I took it out of storage I changed the fuel filter. I could not find a mercury filter so I bought a moller part #33323-10. The cap, rotor, wires and plugs have about 20hrs on them.

My plan is to get a mercury fuel filter and see if that helps. It is the cheapest solution and the only thing I changed. I would appreciate any ideas you might have.

zx14k

i am about shure it is your fuel filter,i had the same problem on my 496,it was a clogged small screen filter just before the water separator.

wjb21ndtown

Same ignition system as before with no mods? It sounds like you're hitting a rev limiter...

If the only difference is the fuel filter, that's probably it, but it seems weird that it only happens at such a high rpm, and the way you describe it you make it sound like it happens instantly at 4200...

misskristy

Oh snap. I changed the filter back to a mercury and toped off the tank with 20 fresh gallons of 89oct. No Change. The ignition system is unchanged from last year.( all msd, blue box, red coil, and marine dist.) The boat ran great when I put it up for the winter and now I lose power at 4200. I noticed last night that from a dead stop if I put the stick down I start to lose power at 3800.

So. Does the carb have a filter in it? Does the fuel pump have a filter in it? I am wondering if foging for the winter could have fouled the plugs some.

My plan: ( one step at a time followed by a test run )
1. Is to check for any other filters.
2. Change the plugs. ( ac mr43t)
3. Remove dist. cap and clean all moving parts and contacts.
4. Change coil.
5. Swear like a pirate and break something.

bajabob

i had same thing last year in my formula check the pick up in the disterbertor mine was rusted .i change that now works good now the other thing is the fuel pump gets cracks in the rubber that will do that to .i remeber i could only run my motor 3400rpm then it start to break up . and it was hard to start . i change that now works good . so i puta fuel presure gauge in . try that i hope that helps

mike tkach

iTrader: (3)

skip step 5,i think step 3 will help,also,replace plug wires

misskristy

Damn thing is the boat starts with the touch of the key. I think the stater rolls over once and its lit.

I will take a look bob thanks.

misskristy

Well I completed step pne and three. I took it for a test drive and there is no change. If any thing it lost more power. I noticed break up at 3950/ 4000.

I need some ideas.

Panther

Sounds like you're starving for fuel once the secondary in the carb opens up or your ignition coil is bad... I've seen both cause similar symptoms. Also, I've seen bad coil wires do the same.

that's what I would start checking.

Any backfiring thru the carb when it happens?

misskristy

No back fire just starts to studer like it is running out of gas.