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booneylander

Secondary Air Injection Pump

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My 451 was making a horrendous noise on cold starts. Traced it back to a loud Secondary Air Injection Pump. I've removed and disassembled the pump and confirmed that the shaft support bearings are bad. 

I was wondering if anyone has had any luck "servicing" the air pump motor. Or do I just pony up and order one from M-B? 

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I do not think I have ever read of anyone rebuilding the pump.  Mine stopped functioning a year or two ago, no emissions testing here so I have no plans to replace it.

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I wouldn't have even noticed if it had quit, but unfortunately it still works, just makes a terrible racket.

I suppose it would be easy enough to open the circuit in the motor and put it back in. No CEL with the failed pump?

For now I grabbed a pump from the other car and have put it in, still functional and quiet, but I'll need a solution for the other car when it's ready to get back on the road.

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