[jeffro788]

Hey guys I have changed oil in many different types of vehicles from cars to tractors, this boat has made me feel real dumb. I thought there was a drain plug on the oil pan, but it is no where to be found. The only thing I can figure to drain the oil is to unscrew the dipstick tube from the side of the oil pan to let it drain. Any ideas?
I never thought in my lifetime I would ask about a drain plug.... it is a 4.3lx by the way.

[Dredd]

Some oil pans don't have a bunghole in boats (although my '93 4.3LX does). If that's the case you'll have to suck the oil out through the dipstick tube with a pump. That's actually the way oil is normally removed on a boat anyway. There should be threads on the top of the dipstick tube for threading the hose onto that runs to the pump.

[jeffro788]

would there be a problem unscrewing the dipstick from the oil pan to drain it?

[Dredd]

If it enters the pan at the bottom then I don't see why there'd be a problem... but I'm having trouble envisioning it entering at the lowest point.

[jeffro788]

It actually does, it goes in the side of the oil pan at the bottom, I am thinking that is where the drain plug is at on a gm 4.3 car engine.

[indykoch]

Jeffro - do you happen to have a tube laying under the engine in the bilge, attached to the oil pan, and maybe with boat's drain plug attached to the other end? Maybe someone added a thru-hull drain tube for easier (but much slower) draining of the oil. I think they usually have the boat's drain plug on the end so when you unscrew it from the stern, you're able to pull on the cable and bring the oil drain tube out with it. Makes draining the oil MUCH cleaner and easier, just have to make sure to warm up the engine very well so the oil drains faster than a trickle. I can't believe there isn't an oil drain plug somewhere.

[jeffro788]

honestly I didn't look for a hose for a quickdrain, but I am fairly certain there is not one. I looked all around the oil pan and went by feel under it and still no luck. Are they usually in the center of the pan on the 4.3's? I really would like to drain it atleast one time and maybe flush it, I just don't like the thought of sludge and anything else that builds up in there.
Also, do you know if that quicksilver 25w-40 with the blue label is synthetic?

[IowaWing]

Don't know if it wil help, but... I just checked my 94 4.3 LX and it has an oil drain plug in the bottom edge of the oil pan on the port side.

[warner0308]

just suck it out the dipstick, its much cleaner. it probally dont have a drain plug they dont want you to change your oil that way because if you spill you never can clean it all,and when you get some water in there and the billge turns on your going to pump water-oil in the water way and if epa sees or any one calls you will get a hefty fine!!

[scubydo]

My 4.3 has the drain plug on the right side of the oil pain. It made such a mess I replaced the plug with the oil drain hose that you just push out the drain hole and catch the oil in your pan. no mess at all now. I got bent over on the hose though, about 85 dollars at Marine Products. Oh well, it is painless to change the oil now.