Knocking noise what could it be

" I just got the motor started

" I just got the motor started. After a few seconds of running, I noticed it making a "knocking" noise. It appeared to be coming from the upper part of the motor.

83 Evinrude 50 hp

Any suggestions on how to clear this up? Any opinions are appreciated!

Thanks,

Jason "

" Ok, here is some more infoma

" Ok, here is some more infomation . . .
I ran the motor for a minute or so, trying to determine the general area that the knocking noise is coming from.
No knock at idle. Starts knocking after I raise the high idle lever and the RPM's come up a little.
The outer breather cover is off and I notice exhaust(?) smoke coming out, along with light sprays of fluid(gas?) spitting out of the carb throats.
The knocking noise sounds like it is coming from or near the carb area, upper half. Could be just because it's easier to hear from there, as the carb throats are there. Sounded the same from in front (while starting) and from each side.
The overheat buzzer then sounded and I shut her down immediately. I couldn't touch the motor near the plugs for even one second.
Then I noticed the water. . . .
The lower unit is in a garbage can full of water. The water is now a milky color, but is clearing after a few minutes. Feels cool to the touch, but is slightly oily.
Also, the water coming from the tale-tell holes (slots) weren't a steady stream, but constant coughs of water. I have recently replaced the impellar and housing.

Where to start now???? Am I doomed to a complete overhaul?

Thanks, all.

Jason "

" Thought of one last thing -

" Thought of one last thing - the engine noise sounds almost like a vehicle does when it is "deseiling down." Like after you turn the ignition off and the car continues to knock and sputter. That is a very similar noise.

Thanks,

Jason "

"Jason.... Fuel spitting out t

"Jason.... Fuel spitting out through the carb throat would indicate that a leaf valve would either be broken or not seating properly.

The knock? Remove the spark plugs, then insert a screwdriver or some such object into the cylinder, and have it rest on top of the piston. Do not apply pressure to the screwdriver yet. You simply want to know where the piston is.

Now, turn the flywheel by hand and get the piston to come up to dead top center, then drag it down about 1" by turning the flywheel.

Now, hold the flywheel tightly and apply pressure to that screwdriver or whatever object you're using. If you can move that piston without moving the flywheel, that indicates that there is play in either the wrist pin area or at the crankshaft to connecting rod area. Let us know what you find.

Joe "

" Did what you said - absolute

" Did what you said - absolutely zero movement. I could barely hold the flywheel still.
As far as overheating - I pulled the **** lower unit again, and sure enough, the water tube wasn't seated in the impellar housing. It was off to the side. Checked the thermostat, opens in a pot of hot water. Also, the shift shaft was orientated to the front! I reset that. I am going to measure the distance from the hole at the top of the shift shaft to the top of the housing to make sure that the distance is correct for neutral.
Is there a fix for the leaf valves or do I have to replace them? If I spray carb cleaner or some such in there, to clean them, won't that hurt the cylinders?
Just want to check, too, is it ok for the water to look like that? I had someone tell me on another posting that it was normal to look like that(a little milky and oily, but clears a little after a few minutes).

THANKS, Joe (again)! I sure do owe you a nice dinner or day of fishing for all this.

Jason "

"Jason.... Your description of

"Jason.... Your description of that knock makes me wonder if a throttle butterfly is loose on its shaft, or if the top leaf plate assy is faulty. Sorry I can't be of more help to you in that area. Let us know what you find.

Joe"

" Thanks, Joe. That is the as

" Thanks, Joe. That is the assessment that I have gotten from another posting as well. It appears that the leaf plate/reed assembly is faulty. I believe those are the same thing.
Is it possible to clean those? I'd like to if I can. Funds are low, trying to conserve whereever I can.

Thanks,

Jason "

" OK, this seems odd. After f

" OK, this seems odd. After fixing the overheating problem (water tube wasn't in impellar housing), the spitting and smoking out the carb isn't happening. Could that have fixed it? Or maybe they were gummed up from old gas and running it cleared them out?

Clueless why this isn't happening anymore . . . any idea's? I don't want to think it's fixed when it really isn't.

Thanks,

Jason "