wet ignition makes boat run crappy??

[wrenchdaddy]

I was at Somerville this weekend and it rained a couple times and after the rain when i went to go out in the boat it wouldn't idle for anything, it was really hard to start, backfiring, misfiring, etc, etc. It would not idle at all it would just stall out and shake real bad. I had to hold it above 1200 rpms or it would shake and stuff. When I accelerated it would hesitate at fisrt but then take off like normal, ran fine under load and cruising just no idle and really hard starting. I have a msd 6al ignition with a msd blaster coil and msd pro billet distributor. The box is under the right gunnel Im pretty sure it didn't get wet. What could cause it to run bad when its wet?????

[Devilman]

I was at Somerville this weekend and it rained a couple times and after the rain when i went to go out in the boat it wouldn't idle for anything, it was really hard to start, backfiring, misfiring, etc, etc. It would not idle at all it would just stall out and shake real bad. I had to hold it above 1200 rpms or it would shake and stuff. When I accelerated it would hesitate at fisrt but then take off like normal, ran fine under load and cruising just no idle and really hard starting. I have a msd 6al ignition with a msd blaster coil and msd pro billet distributor. The box is under the right gunnel Im pretty sure it didn't get wet. What could cause it to run bad when its wet?????
Water & electronics just don't make for a happy couple. What about any other connections, like the terminal board on the back of the motor?? Did it ever straighten up after it dried off? It's either that or water may have got in the fuel somehow..... Only thing I can think of at the moment... :idea:

[Duane HTP]

look for condensation in the distributor cap.

[SmokinLowriderSS]

Water got someplace that doesn't like it. My first bet would be the dist cap as well. Remove, squirt out with some WD-40 (or an alchohol rinse) and then wipe out good. Also check the plug wires, esp the plug ends. I put mine on with a bit of Dielectric grease so they are genuinely waterproof but water gets into seemingly impossible places.

[wrenchdaddy]

ya the terminal board is right behind the motor on the bellhousing, that probably the first thing that got wet. I sprayed it with some silicon spray but didn;t seem to do anything, it did the same thing the next day. I was gonna check the distributor cap but I don;t see how water got in there. It runs great when it dries out.

[Oldsquirt]

An old or "questionable" set of wires will behave that way when wet.

[DeputyDawg]

I had an old Mallory YL marine distributor with crab-cap and that focker always got moisture in it. A little WD-40 a,ways did the trick though.

[Devilman]

Doh!! Forgot about damned distributor cap!! Goodness knows, it happened to me enough washing my engine a time or two!!

[Captain no fun]

Everytime I sink my boat I have to dry out the cap. I always wonder how that part of the boat gets wet! :hammer2: