4.3 no spark, 3 days later and spark.

[loganlaker]

Hi guys. I havee a '95 Maxum 1800 SR with a 4.3LX and Alpha 1. The other day we were out on the lake for he 1st trip of the year, boat was running good and we just finished a tube run and was idle up to the beach when it stalled and wouldn t start. I did some basic checks and found no spark. So i got a tow and took boat home. After 3 days i looked at boat and it fired right up on muffs. I did some research on the thunderbolt 4 ignition before i started it andwas leaning towards the sensor kn the dist.or the module. But now, how do I fix it if it ain't broke. Has any body seen this before?. I am wondering what to do as i do not want to bestranded again. If i had to guess i would say module???
It was 35 degrees celcius that day, engine temp was 150F and oil pressure was good.
Thanks for any help or insite,

Brian

 

[Don S]

Re: 4.3 no spark, 3 days later and spark.

It may have been vapor lock since it was really hot that day. Opening the engine hatch a little can help to let the hot air out of the engine compartment on those really warm one.

View attachment Vapor lock.pdf

 

[alldodge]

Re: 4.3 no spark, 3 days later and spark.

Welcome to the forum

These are rough to determine. If it is heat related it could be many things, but I would think coil, module, breaker or connection. Need a volt meter with you the next time it happens to see where your loosing it. You could go a throw money at it and as I'm sure your aware it is like rolling the dice. Need to find someone else with a boat to go with if you can.

 

[Don S]

Re: 4.3 no spark, 3 days later and spark.

Next time it doesn't run (Yes, you will have to check the problem when it's not working) simply check to see if you have spark.

No spark you have an ignition problem.

Pull the flame arrestor off and pump the throttle and see if the accelerator pump pumps fuel or not.

No fuel, probably a vapor lock. Let it cool down with the hatch open for a while and it should run.

Print this out and take it with you along with a meter and some tools to do the tests.

 

[loganlaker]

Re: 4.3 no spark, 3 days later and spark.

Thanks for the input guys. I will have the troubleshooting tree with me as well as my meter and spark tester next trip.

Thanks again

Brian