350 magnum?
 

Hey guys I was out yesterday running the boat pretty hard for an hour when all of a sudden it started to hesitate it lost rpms came all the way down and then stalled. I could not get it started it just cranked and cranked. Then I let it sit for about 10 minutes and it started right up I ran it for about 5 minutes at 3400 then it seemed ok so I pushed it up to 4000 it started hesitate and I think it backfired it was hard to tell then it stalled. So I let it sit and it started again fine I can the motors at idle to 2000 rpms all day if I wanted to no problem what is the deal here?? My buddy said maybe the timing??
Thanks in advance Harry

Check your fuel filter(s).
Sounds like it may be plugged and starving the engine.
May even be a bad fuel pump.

Backfire through the carb is often a sign of a lean condition - indicating fuel starvation.

Might also be an ignition problem. Sometimes the modules will act up when they get hot - this is a sign that they are going bad.

Check all your harnesses connections and grounds to ensure that they have a good connection. Start with the simple, easy-to-check stuff first.

Re: 350 magnum?
 

Last month you mentioned some serious problems with your engine and said you had "alot of smoke". What did you do about this? This might have been a precurser.....What happend with the smoke. Didn't someone mention doing a leak down test:rolleyes: :rolleyes: Hope it's nothing major....

BH

smoke
 

Well I changed the manifolds and risers and the smoke evened out a little bit. I think someone said it was steam, which would make sense becuase the side that smokes is a little hotter!! I am going to be changing out the whole thermostate housing with the little check balls in it this winter. I think that will even out the water flow a little better!! It has been running great since then!!

Also just before this happened I got a small pinhole in my exhust bellows that go through the hull its on top so water was trickling out of that. I don't think that could have been messing with the engine??

I don't think a leaking exhaust bellows is going to back up inside your boat, do you mean your u-joint bellows? Do you have exhuast flappers in place? It sounds like you might be getting water into your combustion chambers and I would look at your riser gaskets first.

riser gaskets are fine
 

I jsut got home and I wanted to see if the boat would start and all of a sudden it won't even do that!! it just cranks and cranks!! I am guess fuel pump like you guys said. How can I go about checking it how much is it supposed to flow?

First thing is to disconnect the fuel line from the carb, attach a rubber line and lead it to a bucket. Crank it over and see if anything comes out.
I'd also disconnect the pump inlet side and use compressed air to blow back to the tank to see if it's blocked.

Do this first before disconnecting the fuel ine at carb.
I almost forgot, there's a line running from the fuel pump vent to the carb. Pull that off the carb and crank it. If fuel spurts out the diaphragm is torn. Relpace fuel pump.

Wires
 

OK I was checking out the fuel pump and everything seem good so then I went to the ignition!! I took off the coil wire and cranked it I saw a spark and alot of water Massive Condensation!!!! I put the wire back on adn it fired right up!! I changed out the wires dried the coil and it runs great now!! My question is what do you guys do about condensation in your engine compartments becuase I have a awful lot of it!!!

Yeah, wet distributor will do it every time.

Need to make sure your hatch is closing properly, make sure the hatch drain channels are clear of debris and if it has drain lines that they are clear. Be sure the blower vent hoses are not kinked and that air circulates properly in the engine compartment.

When the boat is on the trailer, keep the drain plug out and the nose up and make sure there is no debris blocking the drain hole. If the boat is stored in the water, make sure the bilge is pumped dry before you cover it.

Washing the motor will always result in a wet distributor. Take the cap off and let it dry for a few days with a desk fan blowing across it.

If you've got moisture in the wire sockets, then you will need to dry those all out and use a dielectric grease on all of the boots when you reassemble.

Ok, so I was wrong about it being a fuel problem.

What I did was to coat each plug wire terminal, both ends, heavily with dielectric grease. That'll keep water out of the sockets and prevent corrosion. You can find it at any auto parts store.
I also keep a can of WD-40 on board to spray on the ignition system and under/inside the cap if I find moisture. WD-40 displaces water.