PHOTO"S what does this hose do? 1962 rude 5 1/2 hp

[kodibass]

Hi'
I was wondering what actually does this hose do? what function for the engine is it performing? and does it have a name, like cylinder bypass hose, pressure loop hose etc. I have seen it there on many engines and I just don't know what it does OR what its called, please set me straight , thanks

 

[64osby]

Re: PHOTO"S what does this hose do? 1962 rude 5 1/2 hp

It's called an oil return hose. Feeds oil to the top of the motor / crank.

 

[F_R]

Re: PHOTO"S what does this hose do? 1962 rude 5 1/2 hp

Yep, pumps oil from the bottom to the upper main bearing.

 

[kodibass]

Re: PHOTO"S what does this hose do? 1962 rude 5 1/2 hp

So IT pumps oil/gas (fuel mix) coming in from the intake up to the upper main bearing? how does it do this? sorry to ask a dumb question but I want to kinda understand this because I'm going to try a rebuild on a 5 1/2 soon, and just want to have the basic idea of things once I start tearing it down. I do allot of repairs on these older engines but not much building, or internals' thanks

 

[64osby]

Re: PHOTO"S what does this hose do? 1962 rude 5 1/2 hp

My understanding is - the case has unburnt fuel/oil mix lubing the motor. The excess mix settles or gathers at the bottom of the case. There is an inlet to the bottom of the case, at the low end of the tube. Internal case pressure will pump small amounts of mix up the tube and lube the upper bearing.

I have a Gale 5hp where the tube was bad. As a temp fix I put clear tube on it. I could see the gas/oil mix pulsing up the tube. It is not a continuous flow, or at least mine wasn't.

The head on this motor is shot, (maybe that was the cause). Someone just gave me a replacement head and will hopefully get this thing running again.

 

[Mas]

Re: PHOTO"S what does this hose do? 1962 rude 5 1/2 hp

Which brings to mind...with all the talk about replacing the fuel lines as to be compatible with ethanol...it bet those return lines are overlooked and make burning up the upper bearing a real possibility???

Just thinking,

Mas

 

[jrs_diesel]

Re: PHOTO"S what does this hose do? 1962 rude 5 1/2 hp

That's an interesting thought there Mas. I have a 72 6 HP that I am rebuilding. I think I am going to replace that line now.

 

[1946Zephyr]

Re: PHOTO"S what does this hose do? 1962 rude 5 1/2 hp

Yea, it's best to make sure that that line is not cracked or broken, because you'll not only starve your upper crank bearing of oil, but you'll also make an oily mess under your hood.

 

[F_R]

Re: PHOTO"S what does this hose do? 1962 rude 5 1/2 hp

So IT pumps oil/gas (fuel mix) coming in from the intake up to the upper main bearing? how does it do this? sorry to ask a dumb question but I want to kinda understand this because I'm going to try a rebuild on a 5 1/2 soon, and just want to have the basic idea of things once I start tearing it down. I do allot of repairs on these older engines but not much building, or internals' thanks

"IT"-----well not the hose itself pumping oil. Just transporting it from the bottom to the top. All of the fuel that the motor burns passes through the crankcase on it's way to the cylinders. That is what lubricates the internal parts. Most of it goes right through, carried along with the wind (airflow). But a bit of it "rains" out or splatters up against the wall and drains down. That oil in the bottom is pumped to the top bearing. It is all accomplished by taking advantage of the different pressures in the crankcase. There is no mechanical pump like what you would find in a four-stroke. Thus, nothing to go wrong---except a busted hose.

 

[kodibass]

Re: PHOTO"S what does this hose do? 1962 rude 5 1/2 hp

64osby thanks so much, very clear for me to understand, Now I know what it does and how important it is.. shucks now I have to go look at all my other keeper motors and get to replacing them. thanks everyone!

 

[1946Zephyr]

Re: PHOTO"S what does this hose do? 1962 rude 5 1/2 hp

Yea, you can use weed whacker fuel line, that way you can actually see the fuel/oil mix moving through the line.