QT50 fuel system

Tell me more about the qt50 petcock with pictures too!

Quick overview of the qt50 petcock. This is an aftermarket petcock and not the OEM one. It comes without a sediment bowl which is where bits of rust and similar things can settle out of the gas. You can always add a fuel filter which will do a better job at filtering the gas.

I had a reader send me the above picture of an OEM petcock that was missing the sediment bowl.

Here’s another picture of the same petcock and you can see that it is missing the outer tube that covers the two smaller lines inside. The OEM petcock draws from the longer tube when you have the petcock in the “on” position and the shorter tube in the “reserve” position. The outer tube/cover is probably still inside the gas tank. It is not uncommon for the outer tube to stay in the tank after you remove the petcock. You’ll want to fish around in there and rescue it.

These OEM petcocks are usually rusted or weathered beyond repair but some can be rescued. You can usually find a new petcock for $10-$15 so it may be easier just to buy a new one. You may have to shorten the length of the outer tube/cover/straw on the aftermarket petcocks. You just pull it off the petcock and shorten the end that attaches to the petcock. When you install one, do not over-tighten. If the gas tank is rusty or in poor shape, it can be easily damaged through over-tightening.