D5 pump stops and starts

[allen5055]

I just redid some components in my loop. I have a dual d5 pump Bay reservoir combo. After an hour of bleeding the loop one pump started making a terrible grinding noise. It would grind, then come to a complete stop, then start grinding again. It was running fine two hours ago. I noticed some black flecks in one of my quick disconnects and the bottom of the reservoir. Is something stuck in the pump? What should I do? If I run it on a slower setting it doesn't come to a complete stop and the noise isn't as bad.

I kinda think something is stuck in it and making it spin off balance. This is worse at higher speeds which makes it grind to a complete stop. At setting one it is actually OK.

 

[Skripka]

grinding means a bad bearing or machining...that pump is probably toast or nearly dead. Fortunately you have a backup. I'd clean the loop pull the bad pump and flush like hell your rads and blocks to prevent any of that crap from chewing up your good pump.