Engine loses power then dies

[purplerain810485]

Well, this is part 2 of a thread I made in May 2005, almost a year ago. If you scan through that real quick, you will see what advice and all I got then. I finally got around to rebuilding the carb. And today I took it out for a little test run. I started out very powerfull and then lost power, then got it all back, then lost it, then completely lost it all. At WOT it was below idle, then it died and wouldn't restart. Remembering what was told to me in that previous thread, I tested the following things when I was acting up.<br />1. Pumped primer bulb - no change<br />2. Put my finger on engine - held for 4 or 5 sec.<br /><br />I don't think it's the fuel system, and I'm not very confident in my overheating test, becuase I'm not even sure if my finger was on the right part. Actually, I think overheating is what is causing the problems. Should I get some temp sticks or an infrared temp gun to see what the temp really is? How would I fix it if it is overheating? Impeller? The impeller was replaced in June of 2000. How often do they need to be replaced? Here's some things you should know:<br />1. Carb is freshly rebuilt, and engine is lubed and greased<br />2. New sparkplugs<br />3. Engine is run in dark saltwater.<br />4. fuel tank and line are new<br />5. I have a service manual<br /><br />Thanks for any help,<br />Daniel

 

[fireman57]

Re: Engine loses power then dies

Take a timing light and a buddy with you next trip and have him check fo spark on each cylinder when it loses power. I would suspect a coil but don't go out and buy one until you do this. You can also try it on muffs or a barrel and use a hair dryer on high to heat the coils up and see if you can duplicate the power loss. I also know that you flush this engine throughly after each run in the brine.

 

[purplerain810485]

Re: Engine loses power then dies

Alright thanks, again. I'll try that tomorrow or monday. And yes, I do flush it after each run.

 

[purplerain810485]

Re: Engine loses power then dies

Hey,<br />Today I tried to run it again and it ran like complete crap. Died in a minute or two. I took it off of boat and put in my test tank. It started but would barely stay running at WOT. I pulled one spark plug wire, no change. Replaced it and pulled the other and it died. So obviously that cylinder isn't firing and I need a new coil(s?). Should I replace both or only one? Thanks

 

[RPJS]

Re: Engine loses power then dies

Change both coils, if 1 has gone the other probably isn't far behind, I would also change the plug wires and caps, use copper cored plug wire. <br />While you have the flywheel off clean and regap the points 0.020" also clean all of the ground wire conections.

 

[Walker]

Re: Engine loses power then dies

You need to do a "real" spark test before you start buying coils. Do a search for "Spark Test" you will find a lot of info

 

[Paul Moir]

Re: Engine loses power then dies

Exactly. A healthy ignition system will make sparks 3/8" long or longer. It sounds like you've got an ignition coil failing under load, which is very common for those engines. <br /><br />Here's a good site that will help you out:<br /> Click here. <br /><br />Always replace the ignition coils as pairs. As you can see, they fail by having their insulation crack due to age. So diagnosing a bad coil is usually as simple as haveing a good look at it. If one's gone the next isn't far behind. Iboats sells them cheap anyway (~$15 each, p/n 18-5181).<br /><br />Other possibilities: Cracked spark plug wires, dirty points, leaking top crank seal spraying oil everywhere, faulty kill switch or kill switch wiring.

 

[perkdp]

Re: Engine loses power then dies

condenser maybe