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2000 maxum w/ mercruiser 4.3l - oil change question

newb197

Contributing Member
Here's a silly question..
Can anyone tell me where the oil drain plug is on this motor. Can't quite get my head under it(very tight quarters) barely my arm, and due to the molded bottom on the pan is very hard to make any distinctions. I can see where the dipstick inlet is, is that the plug to drain. Don't quite seem right?

Any help is much appreciated!
 
Can anyone tell me where the oil drain plug is on this motor.

If there isn't a remote drain hose that is pulled out thru the transom drain plug--the hose will be attached to the transom plug w/a chain/wire--then the oil is sucked out of the oil dipstick tube. If it has a pan drain plug it is on the backside of the pan. Leave it alone unless you install a remote drain hose.
 
This one does not have a drain hose set up. If it did the dipstick would be relocated to the starboard side, yes?
As far as the drain plug, you say its on the back side of the pan, but in every parts diagram I inspect I see no such plug/bolt etc. but Its def possible I overlooked it.
I was thinking that the dipstick tube must be removed at the base to fully drain, of course I hope I am wrong.(very tight area here).
And in my case either way, the oil must come out through the bottom as it sucked up a mouthful of water while tubing last week. Boat hydrolocked momentarily while trying to throttle back up(from an abrupt stop) and died out. Started back up and ran normal after a minute or two. No limp home either.
 
there should be a garden hose type threaded end on the dipstick tube.the hand pump threads on to suck the oil out.
 
I would if I could, but this will not completely suck the water out. This must drain for aleast 2 days before my current course of action is taken.
which is:
1. drain oil 2 days though bilge, boat tilted. 2. change filter, add marvel mystery oil(1qt) diesel fuel (1qt) and 5w or 10w/30 (2.5qts). Rn 30 seconds, drain one more full day. 3. change filter, add another mixture of light oil and marvel mystery(1qt) and run for a couple hours under load/way, 4. finally, hopefully all is looking good and I can finally (change filter) put merc oil in and be done.

Of course I must find the root cause also, I believe my first check to be to check the flappers for detioration. Do I have to take the elbows off to get the pipe out of the way?(super tight quarters), I tried like heXX the other day t take the down pipe off and was unsuccessful..close, but unsuccessful just the same.

Any thought/suggestions on my plans (good/bad/ugly) are welcome and appreciated.

I am a new tech, most of my training was in outboards only 12/60weeks were sterndrive product, and only 6 of them were mercruiser. So this is my first water ingestion case in the field. Thanks for any help in advance.

 
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Do what the Bt Doctor says. You are loosing time. That engine is building up rust. If you can't find a hand pump/tank combo at a marine shop then try an auto parts or hardware store and buy a drill pump ASAP! Attach it to any drill and stick the long suction tube down the dipstick hole. The other end has a short dump hose that goes to a large container.

I had an older 4.3L and the oil pan drain plug is in the rear. It's a bitch to get it out; you may even break it off trying. Draining oil out via the bilge will be a dang mess! Below shows where the shutters are on a 1998 model.

http://www.mercruiserparts.com/Show_Pictures3.asp?dnbr=80996998&ivar=images/COMMON/14055.png&inbr=2694&bnbr=270&bdesc=Exhaust+System%28Use+With+Two+Piece+Manifold%29
 
I mean no disrespect to the good doctor. The mercruiser dealership/manager I frequent told me to do this. I had the pump in my hand and he advised me that it would not get out all the contamination. That I must drain it thoroughly through the bottom, and through the bilge was the best way possible because of the low clearance.
He has always been very helpful and on key in the past is all I'm saying.

That being said, I originally was just going to suck out the oil (via the dipstick)and change the oil/filter maybe 2-3 times. I also understand the timeline here... just want to do it correctly, and do right by the customer.

So ok, I go buy the pump (need to get one anyway) then pump it out. Whats next, how do I clean the inside out?
Thanks again, nb
 
Pump out what you can via the dipstick. If you want to check for a drain plug get down and feel for it and try to remove it. If you are successful removing it then put a large diaper or hospital bed pad under the drain. It will contain the small amount of residual pan oil and water. Excess water will run out of the bilge drain. Then follow the dealer's instructions. I personally would also add 8 ounces of WD-40 w/the fresh oil mixture the first time or two.

If the total liquid volume that you pump out after the initial 30 second run is equal to the same amount as you installed, just change the filter, refill w/the oil mixture and repeat the process right away but run the engine at idle for 5 minutes. Each time you do the process extend the idle time 5 minutes so the hot engine oil mixture will disipate residual moisture. It may take 4-6 times until the moisture is dispersed. The final run should be like the dealer recommends. JMHO
 
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