Has anyone had to replace the Aux. coolant pump? It is a small pump on the drivers side underneath the front end just behind the radiator, and mine is whineing something fierce... just wondered if anyone else has tackled this job.

I think I may do that, the MECS Pump, and flush both coolant systems and refill, since I have 51K on the vehicle and both pumps require losing fluid and replacing...

Whatcha think? What's the process for the flush and should I buy a flush fluid and follow some process to properly clean it all out? Can you get everything out afterward?

 

did you have anyproblesm with the stop safely now light or was this preventative work. i am trying to fix my 06 MMH i have changed mecs pump, water pump, thermostat and head temp sensor and all to no avail. the mechanic has told me that this auxiliary pump is coming on i wonder if that not the cause of all my problems.

 

does anyone have a part number for the other auxiliary pump i cant find it anywhere and my 06 MMH has been giving me some SSN problems. i have changed the mecs pump believing it was that, completely unrelated. ended up being the temperature gauge. in the process i changed out the water pump and thermostat. the only thing i can find that isnt working is that small auxiliary pump on the drivers side but cant find any info on it.

 

https://www.greenhybrid.com/discuss/...er-pump-23750/

 

That other pump is for the interior cabin heat. It pumps the engine coolant through the cabin heater core when stopped in EV mode so you continue to get interior cabin heat when the ICE is shut down. I just replaced mine a couple of months ago so my feet could stop freezing at stop lights.
I'm pretty sure this is the part you are looking for:
http://www.fordparts.com/Commerce/Pa...&model=Mariner

 

thanks guys but the part is working fine for me not the problem. vehicle stills cuts off above 3000 rpm. new mecs pump thermostat working water pump fine new temperature sensor.... any suggestions would be greatly appreciated.

 

i was under my 2008 suv and theres 2 mecs pumps from what i saw one is for the main engind and its located on the driverside infront of the electric motor, i might be wrong but thats just me i DIY everything on my hybrid

 

John, I'm having the same SSN issues with my 06 FEH. MECS pump is good on mine and I'm putting in new HVBP fans in a week, but I'm wondering about the temperature gauge you mentioned. Can you be more specific? Are you referring to the engine temp sensor btwn spark plugs 2 and 3, or something else? A part number would be very very helpful. Thanks!

 

I know I'm late to this discussion, but I'm pretty sure Ford has issued a recall for these failing MECS pumps.

http://www.autoblog.com/2014/09/12/f...hybrid-recall/

I had the SSN problem a few years back. I replaced the MECS pump myself. After the recall was issued, I was able to get a refund from the dealer for my costs to buy the replacement pump. Hope this helps.

 

I replaced my OEM MECS pump at about 51,000 miles on spec since I was seeing entries in here about it failing. Ford has a new design pump. If you order one (~$180 several years ago) you should get the new design one. Ford just sent out another recall to replace the original OEM pump. So you may be able to get a Ford Dealer to replace yours as part of the recall.