How does a fuel tank work?

Mostly with continuous pressure from the muffler, and a clunk that flops with the fuel.

Nitro engines use a vent @ the crankcase typically, and no vent @ th

tank, but gasoline engines do. Gas engines have a pump diaphram to pul fuel into the carb and a regulator to control the amount of fuel via vacuum signal. Nitro engines use a pressure system (exhaust pressure) to help the engine run. The exhaust pressure hinda acts like regulator; as rpm's or engine load increases so does the exhaus pressure proportionally

-- freddy warbir

----------------------------------------------------------------------- freddy warbird's Profile:

Ah, but sometimes it does foam and form bubbles, like when you don't properly cushion the fuel tank and the engine's vibration shakes the daylights out of it! Usually, though, a klunk on the end of a flexible tube flops around enough to keep the end down in the fuel.

Morris

Ahaa! Finally I grok the klunk. Thankyou. - LH

Morris Lee wrote: ...> Ah, but sometimes it does foam and form bubbles, like when you don't

Grok. Aint heard that in a while!

Someone just dated themselves!! Heinlein Lives!!!

I didn't think he was from the back country. ;^) Oh and Oscar Gordon said to tell everyone to quit whining and get on with living.

Usually, though, a klunk on the end of a flexible tube

Oops, I or someone in this group should've defined klunk. You got it right -- it's a relatively large cylindrical piece of metal (usually brass) on the end of the fuel line inside the tank that keeps the fuel line submerged in the fuel. Probably got its name from the sound it makes when it hits the side of the tank.

Morris (another Heinlein fan)

freddy warbird Apr 7, 9:05 pm show options

Newsgroups: rec.models.rc.air From: freddy warbird >Nitro engines use a vent @ the crankcase typically, and no >>vent @ the tank

Ahhh...no. Two-stroke engine crankcases must be sealed. There is typically a pressure tap on the muffler, which is connected to the tank. This provides a slight amount of positive pressure in the tank, but not enough to "pump" fuel. The 2-stroke engines suck. The upward stroke of the piston creates a lower pressure area in the crankcase. The differential pressure between the fuel tank (higher) and the crankcase (lower) draws fuel through the carburetor into the crankcase.

Only 4-stroke glow engines have vented crankcases.

Dr.1

freddy warbird Apr 7, 9:05 pm show options

Newsgroups: rec.models.rc.air From: freddy warbird >Nitro engines use a vent @ the crankcase typically, and no >>vent @ the tank

Ahhh...no. Two-stroke engine crankcases must be sealed. There is typically a pressure tap on the muffler, which is connected to the tank. This provides a slight amount of positive pressure in the tank, but not enough to "pump" fuel. The 2-stroke engines suck. The upward stroke of the piston creates a lower pressure area in the crankcase. The differential pressure between the fuel tank (higher) and the crankcase (lower) draws fuel through the carburetor into the crankcase.

Only 4-stroke glow engines have vented crankcases.

Dr.1

freddy warbird Apr 7, 9:05 pm show options

Newsgroups: rec.models.rc.air From: freddy warbird >Nitro engines use a vent @ the crankcase typically, and no >>vent @ the tank

Ahhh...no. Two-stroke engine crankcases must be sealed. There is typically a pressure tap on the muffler, which is connected to the tank. This provides a slight amount of positive pressure in the tank, but not enough to "pump" fuel. The 2-stroke engines suck. The upward stroke of the piston creates a lower pressure area in the crankcase. The differential pressure between the fuel tank (higher) and the crankcase (lower) draws fuel through the carburetor into the crankcase.

Only 4-stroke glow engines have vented crankcases.

Dr.1

Ahhhhh yaaa! But read carefully. I said nitro engines typically. Anyway, I had Saito on the brain when I wrote this. :D