Still Stalling

Hello I have been dealing with a stalling problem since last season. At this point I have narrowed the problem to ignition troubles.

I have: changed points, condenser, plugs, wires, dist. Cap, resistance wire.

During my previous posts these were some of the suggested replies in addition to fuel issues. Therefore I completely went over the fuel system, filters, tank p/u tubes, water in the gas, proper tank venting, fuel pressure etc even ran using auxiliary tanks ? no change in performance. Recently, I double checked for proper timing using a light, noticed the spark was sort of inconsistent this leads me to my concerns about my ignition system.

Currently I am not getting a spark from the ignition coil (it?s very hot). I would just change the coil but I?ve done that before while it was in ?stall mode? with absolutely no better result i.e. the engine would start but once in gear it would cut off. So now my concern is why are the coils burning out? Am I using the proper coils for this engine?I did purchase them from a marine supplier. In addition, if this is a 12v coil which needs an external resistance wire, then why when the resistance wire is cold it allows 12v to the coil + terminal? These 12v are in addition to the 12 coming from the slave solenoid at start up/cranking? do you need both voltages for start up with a 12v coil? Once the motor has started the resistance wire reduces the voltage going to the + side of the coil to 6 volts the boat will run for approx. 30 minutes and then shut down until cool off period ends. I think I?m burning out coils, but I don?t know why! HELP PLEASE!

Oh yeah, I have a 1976 formula 233c with a 351w engine - 2bbl. rebuilt carb. (less than 10 hours on carb. due to stalling)

Re: Still Stalling

Okay I changed both the coil and the points to a Pertronix II system. She started right up, ran good but overheated in fifteen minutes of run time? this is new. Cut off the engine, allowed to cool. Restarted - again ran good unless I tried to accelerate which would cause the carburetor to back fire and again much like the overheating this was new to my engine i.e. only started after the ignition change. But on the brighter side the engine ran continuously for over an hour smoothly unless I attempted to rapidly accelerate. Do I need to reset my timing? If so, what degree? Do I need to readjust the carburetor idle mixture? My instructions with the electronic point system did not mention any of these symptoms. In addition all this happened on muffs in the back yard!

Re: Still Stalling

If you exceeded the water flow from the hose during these hi rpm sessions, you need a new impeller to cure the overheating.

Re: Still Stalling

1) Change impeller as suggested...
2)Make sure ign wires are in proper position....
3)Timing should be 10* BTDC.....
4) Do not play with the carb....

Re: Still Stalling

The boat never over heated prior to installing the new ignition system, i more inclined toward resetting the timing. The impeller was replaced 1 year ago and i haven't put 20 hours on it due to my stalling problem.

When the original points were in the boat the timing was spec'd at 10 degrees btdc, therfore i would think that with the new Pertronix II system the timing would have to be different / higher. I just don't know what the new timing mark should register.

I also thought the new electronic points would automatically adjust the ignition timimg.

Re: Still Stalling

wilburtk said:

The boat never over heated prior to installing the new ignition system, i more inclined toward resetting the timing. The impeller was replaced 1 year ago and i haven't put 20 hours on it due to my stalling problem.

When the original points were in the boat the timing was spec'd at 10 degrees btdc, therfore i would think that with the new Pertronix II system the timing would have to be different / higher. I just don't know what the new timing mark should register.

I also thought the new electronic points would automatically adjust the ignition timimg.

Click to expand...

It's still 10* btdc, the pertronix does not/will not change that...

Re: Still Stalling

You should have 2 wires on the plus + side of the coil, one is a 12v to START only wire, & should go dead once you let go of the key to run position, the other one is your RUN (resistor) wire which should have less then 12v with the ignition on run,,, test these with a volt meter

On the negative side of the coil, it should be one for the distributor (to run), & one for the tach (usually gray)

Somewhere in there is also the wires for the shift interupt switch also, if it's a Mercruiser.

Re: Still Stalling

I reset the timing to 10* and all is well. I will launch this weekend and report back.

Thanx everyone

Wil

Re: Still Stalling

I couldn't wait till the weekend,took off work thursday to lauch the boat. The boat performed great for over two hours before the crackle of thunder rushed us back to the launch. Stalling problem resolved...Thanks all!