I installed the new carteridge on kholer faucet #,k-r648-vs and very little hot water is coming, took the carteridge out and check the hot water pressure in the valve body, very little hot water coming, then check the hot water pressure at the shut off valve, hot water pressure is good, what needs to be done to solve the problem. Thanks... mark

Hi Mark

The only next logical step is to take the faucet supply tube apart from the faucet, direct it into a bucket and see how water flows from the tube (braided hose).

If water flows well out the supply tube then, by your presentation of known facts, the issue is up in the valve body and you may need to use a coat hanger to clean out the hot water port.

Let me know what you find.

Mark