Evirude 175 cooling delima

"When I go back out to the boa

"When I go back out to the boat this week I will check those deflectors again as suggested.

I am also going to get new carb jets.
Do I need both idle and hs jets, or just change the idle jets to see if that rids the lean pop?

I should have #33's right now for idle jets, .033", and based on what u said about bore size, maybe I should try #38, .038" for the idle jets in #1/2 cyl (since these 2 cyls are now 3.564"), and change #3-6 cyl's to #35, .035. (since they are all 3.530")?

Or maybe I should drill the idle jets out one step at a time until I get the lean pop to cease..I do have the drilling capabilities "

"while you have the heads off

"while you have the heads off checking the deflectors, look for a build up of crud in the water passages as well. take your time a clean them out the best you can. a wire brush attachment that comes in a small bore firearm cleaning kit works well."

"Here's the story from thi

"Here's the story from this Friday.
Changed all idle jets to bigger ones, .037 in the top carb and .035 in other 2 carbs. Idle problem did not go away.

Pulled heads to inspect deflectors, all were fine. Found one small piece of gasket on port side, but it would ot have caused a blockage.

#1 piston was damaged again, as top of piston crown was partially gone, with little spots of aluminum appeared to be melted to the top sides of the piston, and the piston was real sloppy (the bearings, piston pin and piston were all new). Did not run again to test the overheat problem because I am done spending $$ on this engine.
Almost $1k into the rebuild and troubleshooting and it appears there is some mechanical issue going on that cannot be seen.

Evinrude 1, Me 0 Time to wait on a new engine!"

"Piston dome gone again usuall

"Piston dome gone again usually indicates that steel was imbedded in the cylinder head from the previous failure. This steel would glow like a glow plug in a model airplane engine and would result in pre-ignition. Damaged cylinder heads must be replaced.

If the above is not the case (reusing damaged head), pre-ignition can also be caused by a slightly fouled carburetor which would make that cylinder run lean. And of course, spark advance timing being set too high would also do it."