In need of help bad!

[at12]

My Dad and I's 97 challenger 1800 has kicked our tails. We have rebuilt both motors and everything has come off of a running boat before. We have been trying to start both engines for some while now. They both have started. We hooked up a trickle battery charger to it after everytime we start it. It will start then after cutting out a couple times it will not start anymore. Then you let it sit for a couple hours or over night and it will crank right back up. We are lost, we have tried almost everything and my dad who has worked on these things for years believes its a bad connection somewhere. But we replaced the wiring harness and every connection get put in with dielectric grease. Any advice would be helpful.

 

[Andy4k6]

Need to start with the basics first

When they won't start do they turn over?
Do they have spark?
Will they run if you stick fuel mix down the carb?

Also when they do run how long do they run for?

 

[Fat Tony]

Try opening the engine hatch cover when attempting restart after running. I'm not sure if there is a fan or not on your boat for the engine bay, but you also may want to turn that on for a couple of minutes prior to restart as well. The oxygen level gets a bit low in the engine bay and needs to be bolstered. Apparently this happens to alot...