oreokid220

I have a slightly warmed over carbed 454 and when running yesterday the boat ran perfectly in the morning. When returning home the motor was idling rough (like it was missing a cylinder or two) and when trying to get going it cleared up and all of a suddle stalled out with the tach jumping from 0 to 5000 RPM with the motor running only at a rough idle. Stalled several times. I managed the limp back to the dock with the tach bouncing and the boat struggling to idle. Could this be because of a bad distributor or coil? The distributor is 8 years old with new cap, rotor, and coil every other year and the wires are 8 years old and look great. The magnets were very rusty though. Fuel is clean with no water as well.

Any other thoughts before I go with a new distributor?

blaquebaja

Disconnect the tach and see if the problem goes away.

oreokid220

Problem still there when the tach is disconnected.

blaquebaja

Have you checked your carburetor floats?

Jonesyfxr

iTrader: (1)

Start with the basics
Make sure battery terminals are tight
Make sure main engine harness is tight
Make sure coilwires are tight

If all above doesn't show anything, try wiggling the main engine harness at idle. If the engine stumbles you can put a hose clamp on the plug to hold it in place.

Hope this helps

oreokid220

Floats are perfect. I did touch all the wire connections thinking the same thing and no luck. Changed fuel water separator on the water and nothing. Would this be related to a bad module in the distributor? I feel it is electrical because of the smooth running in the morning followed by the crazy tach and feeling of a cylinder missing.

Jonesyfxr

iTrader: (1)

A coil that's going bad will act up when it gets hot.

TomZ

iTrader: (2)

Are you using any type of MSD box on this setup? I had a 6AL box that did the exact same thing with my S10. Rebuilt the distributor, rewired, coil, all kinds of stuff! Replaced the box and perfect.

oreokid220

No box on my setup. I just did the cap, rotor, and coil. When the boat starts is runs rough as hell!!! The tach now jumps to 6000 rpm and stays there while the engine is struggling to idle.

I did notice under the cap the electronic pickup is very corroded....is this my problem and should I replace the whole distributor?

Thanks and totally clueless on this one.

BUP

iTrader: (9)

Ignition sensor under the rotor. the newer style is all sealed and has its own ground that needs to be connected on a very clean unpainted part of the engine.