filter in pressure line?

[Monkey Wrench]

Just got back from the LHS (glow plugs) and asked the guy there what he thought. He suggested trying a sphincter valve to avoid the leaning condition as the fuel runs out of the tank.

Just passing along information...

 

[Revo Rancher]

Did he offer you his sphincter valve? WTF was he talking about?!?

 

[4u2nv]

my sphincter valve is clogged..

 

[Monkey Wrench]

Think about it, Rancher...

 

[Revo Rancher]

And I repeat...

Did he offer you his sphincter valve?

I knew it was a joke, but I can only imagine someone at a LHS actually convincing someone of this. "Muffler bearing, anyone?"

 

[godale03]

heee heee heee.... he said sphincter!!!


Telling someone that is like telling a newbie PC user that in order to find his forgotten password they need to type format c: at his DOS prompt. Funny stuff man!

 

[neobart]

my sphincter valve is clogged..

I heard the best way to unclog a sphincter valve is to blow in it.:OMG:

 

[Plaidfish]

I heard the best way to unclog a sphincter valve is to blow in it.:OMG:

Um don't you mean OUT????

 

[McoupeRS4EVO]

haha this reminds me of a story,,.

in high school auto shop years ago..

We had a 396BB out of a vette or something.

and my buddies girlfriend was all like i took auto for 3 years I know all about engines.. I wad like ok you douche( I hated this woman) ( hated her with a passion) So I was like fine point out the systolic motivator.

My buddy played it off like it was a real part.. and after checking with him and making sure i wasn't messing around with her. she started pointing at things.. she pointed to every part. and i was like and you took auto for how many years. and we kinda just left the class and laughed our asses off on how the flavour of the week was a fiddlesticking poop popsicle with a bullshit center.

 

[jetmechG550]

Easy coup, last comment was a little heavy for this area.

 

[supersavage]

So to get back on track, tell me if my logic is messed up...

Adding a longer pressure line from the exhaust to the tank would essentially have more of a leaning effect on the first half tank than a richening on the second half???

Longer hose - more restriction - less pressure in tank - leaner carb...

As tank empties - more volume - less pressure in tank...

If this is way off, how does it work?

 

[hugo]

I think it's the ion sensor

 

[Revo Rancher]

SS, that sounds about right. The slight restrictiveness of the filter accomplishes the same thing. In some cases there is not enough room to add more fuel line. Adding fuel line is more popular as it also extends the tim eyour rig can sit upsidedown on it's lid idling before it runs out of fuel.

 

[SuperMaxx83]

so what were trying to say is if your 1st half of the tank is leaner then so will your 2nd half and that means when you tune it it stays that way for the whole tank and you dont have to worry half way throught the race about your temps

 

[supersavage]

Woo hoo, I think I may understand...

 

[kx250ryder]

I thought installing a fuel filter was to prevent a lean bogging condition that occurs when the tank is full as explained in this article (about two thirds the way down the page titled "The Dreaded Full Tank Lean Bog"):

http://www.rchobbies.org/engine-tuning.htm

 

[Jeep]

kx,
that's interesting reading, thanks for the link.

Jeep

 

[kx250ryder]

I had a problem with the lean bogging mentioned in that article, so I bought the biggest fuel filter I could find (happened to be a blue anodized OFNA unit) and used that. I never even made the loops of fuel line like they said, but it still worked. I don't get as wild of temperature fluctuations from beginning to end of tank anymore, and the car doesn't hesitate when I re-fill it.

My take on it is that the fuel will collect inside the hollowed out filter, but the large space will allow the air to move around it keeping the line from being clogged.

Here is my buggy with the setup:
https://www.rcnitrotalk.com/forum/showpost.php?p=385140&postcount=108

 

[Jeep]

Thanks kx,
that article made alot of sense, most folks don't realize that when an engine is running high rpm and then the throttle is suddenly shut off there is a tremendous vacuum created in the intake(be it a 4 stroke, 2 stroke, or these little nitro burning 2 strokes) and in the time that the engine winds down, that vacuum is transferred into the combustion chamber, and then transferred to the exhaust, and if there is fuel sloshed up by the pressure line, it will see that vacuum and be sucked into the "normally" pressurized line.
I'll be getting a reserviour on my next parts order.

Jeep