Motor will not Turn Over

[cv1973]

Last spring I had a new Mercruiser 3.0 LX put in my boat. About halfwat through the summer the fuel pump went out and I had it replaced, ran fine. A couple of weeks ago I decided to prepare my boat for an up comming camping trip. Anyway the boat wouldn't start had a loud clicking noise, replaced the starter and the boat fired right up. I left the boat running for a good 15 minutes to make sure everything was running properly. I took my boat to the lake this past weekend in hope to have an enjoyable time on the water, well the problems started as soon as I put it in the water. Got the boat of the trailer and was heading towards the dock to pick up passengers and the boat just died. I kept trying to start it and it would crank but not turn over. When it did finally turn over it was very weak and spit and sputter for a few seconds and cut off. I have changed the coil, starter, battery, the carburator was rebuilt at the time the new engine was installed. Another thing is that the carb is getting fuel but the enginie is not turning over. One thing that I did notice a couple time when trying to start it was a puff of white smoke coming from the carburator.

Could it be that I need a new distributor (not enough spark) or a new or re-built carb?

Any help would be great

 

[danond]

Re: Motor will not Turn Over

Crank and turn over are the same thing - the motor is being turned by the starter. I think you mean "it wouldn't fire".

Don't throw parts at it to fix it. Start with one thing, verify that it's working properly.

Your issue sounds like timing is off or fuel is not being delivered properly. Do you have the facilities/tools to check timing (you need a timing light) and carb settings?

 

[cv1973]

Re: Motor will not Turn Over

Thanks for the reply, yes I did mean fire. I do not have the facilities so it looks like I will be taking it back to the shop. I guess what puzzles me is that it ran fine when I hooked it up to the hose and it ran great from the boat ramp to the dock, no indication of anything wrong when I was cruising to the dock and when I put it in "N" that is when it died and wouldn't fire again all weekend.

 

[Don S]

Re: Motor will not Turn Over

Sounds to me like you have water in your fuel tank. When you ran it at home on muffs, the bow of the boat was lower than the back. Water would go to the front of the tank away from the fuel pickup. In the water, the bow is higher and the water goes to the back of the tank and you pickup water, not gas.
I've already fixed 5 boats with this problem this spring.

 

[cv1973]

Re: Motor will not Turn Over

When I ran the boat on the muffs it only had about 3 gallons of gas and the boat was hooked up to my truck so it was prety level. I filled the tank with premium before I went to the lake and i also put the same gas in my truck.

 

[J. Mark]

Re: Motor will not Turn Over

Water condensates in tanks over the winter because boats don't use a sealed tank like your car or truck. It takes very little water to make an engine run poorly or not at all. If you have a fuel water separator filter, it is time to change it. When you do prefill it with gas that is known to be good.

Also check that your distributor is clamped in place firmly. When I bought my boat the distributor was loose enough that it could be turned by hand with just a little effort. Running an engine with a slightly loose distributor clamp will change the timing til it won't run in very short order.

 

[arrkerr]

Re: Motor will not Turn Over

I'd sure check the timing though. A timing light is really cheap and an invaluable took for checking for spark, as well as checking the timing.

If you had a big puff come out of the carb, that sure sounds like really bad timing.