Re: getting frustrated on recovered dunked motor

Posted by Lee (209.213.155.75) on October 26, 2003 at 07:51:54:

In Reply to: Re: getting frustrated on recovered dunked motor posted by boatman on October 26, 2003 at 05:58:52:

Your suggestions are appreciated & do make sense, but I have went thru most of them long ago.

It ran OK, (I thought) in the tank after the dunking, (7 hours total), until I took it for a fishing trip. I ususally start them with muffs the night before just to save time & wasted effort. This day was a late tide so I did the run check early AM. It would not start without cleaning the plugs & starting fluid in breather housing. OK, I got it going & it seemed to run OK. I took off for the fishing trip, had it in the water trolling within an hour or so of the start/run check. After trolling for 2 hours, it died. When I got it home, I fought it the whole next day, double & triple checking about everything & found it would run at a mid speed, but at a trolling speed, the top plug would not fire. Spark gap jumped the 7/16" on both coils. But thats when I swapped coils off the other motor just for jollies, no change.

I got frustrated & took it to a mechanic. I had replaced the L78V plugs with L77JC4s. The new L77JC4s he put in, he found that they did not seat tight on the gasket/washer. I am careful to tighten them in, but not over tighten as to not strip the threads. Apparently the L78Vs had a longer thread angle at the bottom, & carbon had built up at the bottom of the plug hole threads. He just chased the threads, put the new plugs in & was happy with how it ran.

When I got it home, I tried to start it & then started running into these other problems.

As per your suggestions;

(1) New proper plugs installed by the mechanic on his attempt, but I now have to clean them & bead-blast to remove excess oil if it sets over a few hours, before attempting to pull start it again. Electric starting it will usually start, but only after extended cranking.
(2) Exchanged ALL ignition components including timing plate & flywheel off another running engine, but left the new power pack on. Also cleaned All plug in connections & ALL the grounds under coils, PP etc. The other motor that electronics was swapped off of still runs fine.
(3) Removed & totally cleaned carburator in 1st dewatering attempt, then after getting it back from mechanic, I also tried to rebuild the fuel pump, but finally put new on, & new fuel line between FP & carb. Have not removed carb to check it the 2nd time however.
(4) Possibly a small fish had gotten into the exhaust system & be blocking it, as I removed one critter from under the carb & cowling when doing the 1st dewatering.

I even gave some thought as to a small fish got thru the carb & into the reed plate area of manifold. If I take the carb off again, I will also pull the intake manifold off & check the valve plate & reeds.

Maybe the problem lies in the LH muffler bearing being loose.