86 Johnson 70HP - mystery tube

[HugoB]

While changing out the water pump I noticed this tube . Is it supposed to by lying there disconnected, it it some kind of an air intake tube? Is there supposed to be this much oil in the housing? Are these two symptoms related?

I should also mention that the VRO cover was attached using only 1 screw. I assume that's bad style??

P.S. I inherited this engine..

 

[EN2]

Re: 86 Johnson 70HP - mystery tube

That tube is to be connected to a nipple on the backside of the air box. The black part that is bolted to your carbs.

 

[HugoB]

Re: 86 Johnson 70HP - mystery tube

Sorry I am new to this, but is the air box the black plastic component on the front of the engine, prominently featured in the picture posted in the original post? What is this tube for?

Thanks for help with this. I read through the manual but I couldn't find anything on this..

 

[schematic]

Re: 86 Johnson 70HP - mystery tube

Yes, if you follow the hose back 2 inches, you will see a hose connector on the back of the black plastic housing. Yes it will make a mess if unplugged.

 

[jtexas]

Re: 86 Johnson 70HP - mystery tube

... What is this tube for?

Thanks for help with this. I read through the manual but I couldn't find anything on this..

That hose is there to scavenge the oil that collects in the air silencer cover during normal operation, and deliver it to the crankcase. Some say the lower crank bearing needs it, others have said that the #3 cylinder will fail if its missing, and I've also heard that its only purpose is to avoid making a big mess...I don't know which if any is right, I just always put it back whenever it slides off.

 

[HugoB]

Re: 86 Johnson 70HP - mystery tube

Thanks, I found it. You can't see the nipple it fits on without taking of the whole air box. It was also a ***** to put back on since it's short and the way the air box is shaped it makes it very difficult to put back on. Had to use pliers to hold the tube in place while pushing on the air box.
While checking the parts makeup for this part of the motor I noticed I was missing the air box cover gasket, so now I have to wait for that to come in. I should have done this earlier in the year so I wouldn't be missing valuable water time!

 

[jtexas]

Re: 86 Johnson 70HP - mystery tube

that airbox cover gasket is not mission critical.

Install it at your next opportunity; meanwhile, go fishing!

 

[kenmyfam]

Re: 86 Johnson 70HP - mystery tube

that airbox cover gasket is not mission critical.

Install it at your next opportunity; meanwhile, go fishing!

Agree 100%