Airbox Drain Hose 82 KZ750E3

I am pretty sure I already know the answer but just want to confirm. The hose from the small nipple at the bottom of the air box , should there be a plug on it. The parts diagram does not show one and frankly I have had bikes that use a plug, and those that don't. It is to drain any oil, but it also doubles as a fuel drain since my carbs overflow back through the carb inlets (ie. no overflow tubes on the inside of the carb). If I plug this and the carbs overflow for what ever reason it is going places I don't want it to go.

So assuming that this is not supposed to be plugged at the end. It is on the clean side of the filter but there is a small foam filter that it passes through at the bottom of the air box. Can someone just confirm that no plug is needed.

Thanks

I think stock has a plug but you don't need it. Just make sure the drain hose routes to the side of the rear tire in case you get a carb overflow.

That is what I figured. Double checked the internal filter at the bottom of the cartridge filter and it does filter out any air being sucked in by that hose.

Wish they would have stuck with the internal overflow tubes vs just emptying into the air box then the crank. My CB750 has them and as much I as hate seeing fuel on the ground on occasion, better than not seeing it and it disappears into the engine. At least with no plug now it will leak on the ground.

I don't know. The diagram for the 81-82 750E doesn't show a plug & there's a drain hose shown in the diagram. I wouldn't plug it. In addition to fuel & oil, another possibility is water getting into the airbox.

Agreed.

There is actually another drain on the dirty air side at the bottom of the filter for ingested water. No hose on that one, just drains on top of the swing arm. This drain hose is more for the oil collected from the breather. On most bikes I have worked on the hose is plugged and have a clear line to see when there if is oil in it. I am guessing they decided against the plug so that the fuel could drip out on an overflow, hence the small filter that covers this drain hole. Otherwise unfiltered air would be introduced to the engine. That being said, the nipple is so small that I could not see much getting in there short of a ride through the desert.