Comet 0205.0059 Connecting Rod for MC25 Pump (2 pieces)

Comet 0205.0059 Connecting Rod Kit (2 Pieces)

The genuine Comet connecting rod assembly kit for MC20 and MC25 diaphragm pumps. The connecting rods link the eccentric shaft to the pistons, converting the shaft's rotation into the piston strokes that flex the diaphragms. This kit includes two rods, one for each of the pump's two pistons. Replace them if they're worn, scored, rusted or damaged, typically after a pump has run with water in the crankcase or has developed a knock.

Specifications

Related Crankcase Parts

From the Comet MC20/MC25 parts breakdown. Call us at 602-371-1993 to order any of these.

Frequently Asked Questions

Why do connecting rods fail?
The most common cause is water in the crankcase from a broken diaphragm. Water displaces the oil and lets the internal parts rust. Comet's manual says that if you find water in the oil and can't rebuild the pump right away, drain the water and add oil (even used oil) to stop internal parts from rusting. A knocking sound or excess play while running also points to worn rods.

Should I replace anything else while the crankcase is open?
Inspect the connecting rod rings and washer, the pistons and sleeves, and the eccentric shaft for wear or rust. If the rods failed because of a broken diaphragm, replace the diaphragms too, and refill with fresh oil after flushing out any water.

How do I prevent this?
Check the oil regularly. Milky or watery oil means a diaphragm has failed, so stop the pump and repair it right away. Comet recommends checking diaphragms at the end of every season, and replacing them every year when using strong chemicals.

Related Products

• Comet 0003.0011 MC25 Pressure Accumulator
• All Comet MC25 Pump & Parts
• All Comet Diaphragm Pumps

Downloads

Download Comet MC20/MC25 Parts Breakdown

Download Comet Diaphragm Pump Instruction Manual