Anyone having problems with your MCP350 pump?

Ok for starters I've read a few posts about people having problems with these pumps at start up. I've made an interesting discovery in the past few days concerning the nature of the problem. I discovered that my pump only acts up if I've recently drained my loop or have shut down the systen before getting out all of the air bubbles.

I ran many test over the past few days and I feel confident in saying that if you are having preoblems with this pump you need to try to make absolutely sure that you've gotten all the air out of your loop, especially the pump. My pump failed to start almost every time after letting air get down into it and never failed once after completely bleeding my system.

I had same exact problem with a couple of em.

I think this is a problem with a lot of pumps. With my Hydor L35, I have experienced this as well. Get it going, or get the air out, and everything is fine.

I usually have to shake it at first to get the air out then it works just fine. As long as there's no air in the pump it works perfectly. I wonder how many pumps are RMA'ed because of air bubbles. I bet the number would be pretty surprising.

laing ddc is working with me on this and this has to do with the in rush or lack of current to the pump. A new improved model will soon be out, I got it today and i will begin testing Tuesday [prototype] looks identical.

Heres my results after having to knock my pump around to get it too start and it did not have anything to do with air bubbles om my side.

1rst failure after modding the top for more flow and also noticed white residue due to cheap coolant and possibly not flushing my radiator before running it.

2nd drained system added iodine and just distilled water got 10 good starts before failure. took pump apart both times and cleaned completly.

3rd flushed system with 50% vinagar and 2 tablespoons salt for 10 minutes. Drained and flushed with clean water. Added 30% dex-cool GM antifreeze and tap water going on 10 days and no failure so far at all.

Whats different about the new ddc pump?