What is the plug with 5\16 allen on the front of oil pan on 2003 88inch twin cam harley engine?

I cannot post you a picture but the engine oil drain plug is on the left hand front of the oil pan. It is a 5/8 inch hex plug with a 1/4 inch allen socket in its center.

Engine oil is to the front of the oil pan underneath the bike. Trans is on the right side of the pan. Both are large bolts that also have smaller allen holes in them. Do not remove the round plugs that only have allen heads! The primary drain is under the clutch cover.

I think the engine oil drain is on the bottom of the oil pan and the transmission oil drain is on the side. I'm really not positive as I work on the older models that have both drain plugs on the bottom of the pan. On my 1994 WideGlide, the drain plug in the middle of the pan is the transmission drain and the one on the front left bottom is the engine oil. Go to this site as look your bike up. Look at the Transmission picture of the housing. http://www.bikebandit.com

Good Luck
Steve

I'm not a Twin Cam mechanic but I do know that the oil tank on your Wide Glide is on the bottom of the transmission. I think it has two oil drain plugs, one on the bottom of the pan and one facing the front of the bike on the left front corner of the pan. The transmission drain is the socket head pipe plug on the front of the oil pan, I think. One of the plugs on the bottom of the engine is simply a drain for the cam chest. If you're working in that area, you can drain the oil out of it by removing the plug. It'll refill itself once you start the engine. This should be the plug directly below the pushrod tubes. I'm not sure of what the other plug you pulled was. Like I said, I'm not a Twin Cam mechanic. I work on the older models like the Panhead, Shovelhead, Evo, and Ironhead Sportys.
Go to this site and look up your bike and see what these plugs go to. http://www.bikebandit.com

Good Luck
Steve

On your Ultra, the oil pan is on the bottom of the transmission. If you pull the oil dipstick, you'll see that it goes down into the pan located under the transmission. The engine oil drain is the drain plug nearest the left front of the pan or in the middle of the pan. If the bike is on the side stand when your drain the oil, I'd pull the plug in the front so that all the oil comes out. If you pull the one in the middle, you must stand the bike up straight to get all the oil out. The transmission drain appears to be the pipe plug in the front of the oil pan. Go to www.bikebandit.com and pull up this drawing. It will show you the pan and the gasket. Notice the gasket closely, the hole down through the front of the pan looks like it goes to the transmission and the other plugs look like they are for engine oil. The plug you pulled out is the drain for the cam chest, I think. I'm not a Twin Cam mechanic but I'm pretty sure that I'm right about that particular plug. You probably didn't get any more than a couple of ounces of oil out of that area.
http://www.bikebandit.com/1999-harley-davidson-flhtcu-i/o/m1173#sch145241

Good luck
Steve

I'm not that familiar with the Twin Cam engine but from what you're saying, Harley has a drain or something in the cam chest of the Twin Cam engine. This is something new for Harley as the previous engines had no means of draining the cam chest. I would imagine that this is what the oil you saw was, oil in the cam chest waiting to be pumped back to the oil tank by the oil pump that is located in the cam chest. When you restart the engine, this area will again fill itself to the proper level.

Good Luck
Steve

I am referring to the drain pan on the Harley Davidson Twin cam 88 engine.

The engine oil drain hex bolt is located on the right side of the motorcycle (as you are seated on it) and is removed/installed horizontally.

Transmission oil drain hex bolt is located on the left side of the motorcycle (as you are seated on it) and is removed/installed vertically.

if you look under the bike you will see a long pan. On the front of that Pan are two bolts (may look like allen head bolts too). You want the one on the left side of the bike. I think its a 5/8 socket

You dont say what model bike BUT .... if its an evo.... you have to drain the oil out from the oil tank. Theres an oil drain hose. It doesnt drain thru the engine. If its a twin cam it does...Maybe you were low on oil ? Theres also oil in the filter. A quart might be about it in that case