1985 Force Carb Flange. What is this barbed fitting on the intake under the carb?

[777funk]

My dad sent me this picture. I'd guess maybe it's a pulse for the fuel pump but am not there to see it.

 

[tg3690]

My dad sent me this picture. I'd guess maybe it's a pulse for the fuel pump but am not there to see it.

Kinda hard to tell exactly with that pic, but I believe that is part of the recirculation system.....that hose should go back to the cylinder drain cover, or "dog bone" as they call it. That system takes excess fuel from the cylinders and routes it to the intake to be burned up. If it is plugged up it can cause problems, bad idling, etc......

 

[Mc Tool]

Youd sorta have to think that hose was supposed to be on that barb .....no?

 

[777funk]

Youd sorta have to think that hose was supposed to be on that barb .....no?

Naturally, and he put it back on the barb. My Force 50 doesn't have this, so the question was, what's the purpose of the hose.

 

[Nordin]

I think the later Force suppose to have these recirculating hose going from the top cylinder side just under the flywheel and to the "dog bone" cover plate.
But I can be wrong.
As this engine block construction is from the mid 60.es (West Bend brand in the beginning) the unburned fuel as a two stroker produce has been routed in different ways.
The early engines just routed the unburned fuel from the "dog bone" into the midsection and out with the exhaust. The second way they routed the unburned fuel from the "dog bone" into the crank case just under the carb intake flange and the third way as I know is the one the hose goes from "dog bone" and up to top cylinder just under the flywheel.

 

[777funk]

I think the later Force suppose to have these recirculating hose going from the top cylinder side just under the flywheel and to the "dog bone" cover plate.
But I can be wrong.
As this engine block construction is from the mid 60.es (West Bend brand in the beginning) the unburned fuel as a two stroker produce has been routed in different ways.
The early engines just routed the unburned fuel from the "dog bone" into the midsection and out with the exhaust. The second way they routed the unburned fuel from the "dog bone" into the crank case just under the carb intake flange and the third way as I know is the one the hose goes from "dog bone" and up to top cylinder just under the flywheel.

Thanks. Learn something new everyday.
I always figured there was no unburned fuel besides the richening for lube and that everything that went into the crankcase got burned eventually.

I guess it would eventually puddle at the bottom of the engine and create an issue. I suppose chainsaws don't have this since the position moves around so much as they're run.

 

[Mc Tool]

2 stroke oil can "fall out " of the fuel mix and pool at low points inside the crankcase , usually at the lower side transfer passage area . There is often a hose going from this area up to a main bearing and the pulsing of the crankcase pressure pushes this oil up to the bearings (I have clear tubes on my Tohatsu and you can see it happening ). The dont usually feed to the bottom main bearing as either gravity or an internal passage does this . There is also often a hose from the bottom cylinder lower transfer passage that goes back to the induction just after the carb . I guess the theory is that if the oil is going to pool may as well make use of it . It does all eventually go thru the combustion chamber .
You may have noticed ( blind if you didnt) that if you gun the motor after a period of idling you get a good cloud of smoke ....this is some of that pooled oil getting stirred up and fed thru the combustion chamber and burnt .

 

[Mc Tool]

Thanks. Learn something new everyday.
I always figured there was no unburned fuel besides the richening for lube and that everything that went into the crankcase got burned eventually.

I guess it would eventually puddle at the bottom of the engine and create an issue. I suppose chainsaws don't have this since the position moves around so much as they're run.

I think this is peculiar to outboards because the motor is lying on its side with the crankshaft vertical.....gravity an all that ,

 

[Mc Tool]

2 stroke oil can "fall out " of the fuel mix and pool at low points inside the crankcase , usually at the lower side transfer passage area . There is often a hose going from this area up to a main bearing and the pulsing of the crankcase pressure pushes this oil up to the bearings (I have clear tubes on my Tohatsu and you can see it happening ). The dont usually feed to the bottom main bearing as either gravity or an internal passage does this . There is also often a hose from the bottom cylinder lower transfer passage that goes back to the induction just after the carb . I guess the theory is that if the oil is going to pool may as well make use of it . It does all eventually go thru the combustion chamber .
You may have noticed ( blind if you didnt) that if you gun the motor after a period of idling you get a good cloud of smoke ....this is some of that pooled oil getting stirred up and fed thru the combustion chamber and burnt .

Here are some pix of said tubes on my Tohatsu

Yes its the wrong decal for that model and its on backwards and the whole thing is the wrong colour but you should have seen it when I got it ....brush painted with house paint .

You can just see oil bubbles in horizontal tube just by joint in crankcase halves .

 

[Mc Tool]

Nother pic