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kstumpenhorst
06-24-2011, 12:25 AM
I own a 2000 maristar 230 vrs and last year while winterizing I noticed where my knock sensor was looked a little corroded. This was my first year winterizing and I don't think whoever did it last made sure the plug was in all the way and it got a little rusty where the water was dripping out. Now I bought a new plug and it won't thread. What can I do, orndo I need to run a tap through? Also how do I drain my oil. Where can I run the drain hose too? Thanks a lot

mtajpa
06-24-2011, 12:53 AM
You might try poking a screwdriver into the hole and try to clean out any rust that has plugged up the hole. then try a small wire brush to clean the threads. If that doesn't work you will have to run a pipe tap into it to clean the threads.

You oil drain hose should go out the rear drain plug hole. Mine has about 8 inches once it is thru the rear drain plug hole.

kstumpenhorst
06-24-2011, 06:41 PM
Thanks mtajpa! I tried the screw driver and was going to go to a pipe tap next but will try the wired brush first. Where is my back plug. I don't see it anywhere. I must be blind. Lol

mtajpa
06-24-2011, 08:18 PM
It is the rear drain plug located in the back of the boat between the exhaust flaps. I assume you would have one but maybe I am mistaken.

here's a pic of mine. The guy in the middle has his right hand also on it. Right above the rudder.

JimN
06-24-2011, 09:40 PM
Thanks mtajpa! I tried the screw driver and was going to go to a pipe tap next but will try the wired brush first. Where is my back plug. I don't see it anywhere. I must be blind. Lol

Don't use pipe tape- it decreases the sensitivity of the sensor to the frequencies it's supposed to pick up. The best thing to do is use a thread chaser to clean out the hole and if it still won't thread in, re-tap it. If that still leaks, drill it out, to fit a brass fitting that will match the sensor and make sure the sensor is mounted directly into metal.

Make sure you're looking at the side of the engine with the starter.

kstumpenhorst
07-24-2011, 03:22 PM
Thanks everyone. Got it all figured out. Ran a pipe tap through it and am enjoying the water