Kayser Bypass Valve
Posted: Sun Aug 17, 2025 3:05 pm
I bought a new factory-style bypass valve this week. I discovered in the process that the OEM Bosch unit is no longer available, or at least I couldn't find one at any of the usual online stores. Dealers still sell them, but for $200 or so. So, I threw the dice and bought the Kayser valve now offered at places like Pelican and AutohausAZ, etc. Turns out Kayer (pronounced like Kaiser Hospital) is a family-owned German company. I mention that because this valve is a dead ringer for the original Bosch unit. They are either amazingly good at replicating parts or, as I suspect, they are using Bosch's tooling to make it. It even has the same stamp mark where the Bosch logo went, except it's left blank on the Kayser. Same rubber bladder inside too. Works fine so far too... At least on initial review, it seems like the quality alternative to the Bosch unit.