The RB-155 carburetor repair kit, for trimmers and blowers. The metering diaphragm, black rubber, a rectangular flange, a metal center plate of five large holes around a small pin, swelling and contracting to draw fuel; the square main gasket sealing the joint between the carburetor and the body; the shaped gaskets each covering a different chamber; the spring handling the return, the needle valve cutting the fuel, and the pins and clips the locating pieces easiest to lose on a teardown. When the rubber has aged, the idle is rough, acceleration is gone, or fuel weeps under the carburetor, one teardown swaps the kit and the body keeps working. On fit, lay the old parts out and match them, fit the gaskets dry with no oil, press the diaphragm flat with no wrinkles, the spring the way it was, test the needle valve, and check the idle and the joints once running. For the RB-155 and RB-164 family carburetors, with the C1M-S series, the BG66 and BG86 checked against the old parts, and fit not guaranteed for every one.

 FAQ 

Q1: What is in this kit?

A carburetor repair kit, the metering diaphragm with a rectangular flange and metal center plate, a square main gasket, shaped gaskets, the spring, the needle valve, and the pins and clips, the worn pieces of a trimmer or blower carburetor in one pack.

Q2: Which carburetors does it fit?

The RB-155 and RB-164 family carburetors, also listed for the RB-180 and the C1M-S141 to C1M-S151 line, on machines such as the BG66 and BG86. Fit is not guaranteed for every one, so lay the pieces against your old parts and check the diaphragm and gasket shapes before ordering.

Q3: Do I need a new carburetor instead?

Usually no. What fails is the rubber and a few small metal parts, not the body. One teardown with the kit swaps the diaphragm, gaskets, spring and needle, and the body keeps working, cheaper and more durable than swapping a single piece and making do.