keithp83

I have an 1986 5.7 260 mercruiser that's sputtering and dying at WOT and about anything over 3/4 throttle. If I keep it under 3000 rpm it seems to be ok. If I open it up from about 3200-3800 it'll start to fall on its face.. Almost like fuel is cutting out. Today I replaced all the plugs wires cap rotor fuel water separator and the fuel filter inside the Rochester quadrajet, the filter looked a little dirty but nothing too bad, I don't know when the last time it was changed since I've only owned the boat for a couple months first time I drove it it was fine, put $100 in fuel at a gas station on the way up the lake brought it home put captains call exhaust on it stopped at same gas station on the way back up put another $100 ran great for first 30-40 minutes or so then started having the problem.. Both times I used the marine additive for the ethanol. I'm stumped on what to do next? Could it be a batch of bad fuel? Could it be a fuel pump starting to go?

Jonesyfxr

iTrader: (1)

I had a similar issue last year. I replaced the fuel pump and it was better, but would cough at WOT then would be ok for a bit then cough again. I feel my issue is in the fuel pick up. I will be pulling that out shortly to nspect it.

keithp83

I hope it's just the fuel pump.. Looks like to do anything with the tank would be a huge pain in the ass haha