MECS Pump Lifetime
 

2006 FEH.

I replaced my MECS Pump (the OEM pump) at about 50,000. This was on spec as I'd seen many entries here about that type pump failing around 50,000. I replaced it with the upgraded pump.

I'm now at 192,000 and have had no problems with it. My pump is now at about 142,000 and about 4 years of age.

Anyone out there have any info on projected lifetime of the upgraded pump?

Re: MECS Pump Lifetime
 

GPSman1 posted he got 100k out of the replacement pump.

Re: MECS Pump Lifetime
 

I just replaced original Bosch MECS pump with Dorman pump.
The main difference of the two pumps is: Bosch pump use BRUSH DC motor, Dorman pump use BRUSHLESS DC motor.
Brushless DC motor is much more reliable than brush DC motor. If you already have Dorman pump on your car, you don't need to replace it anymore.
I open the original Bosch pump, there are lot of carbon powder inside the motor and the brush worn out already.

Re: MECS Pump Lifetime
 

OK, I have 140,000+ on mine now (193,000 on my FEH since new). You're right about the projected lifetime of brushless DC motors. Probably won't need replacement any time soon. I suspect that the old design motor was configured with a start-stop feature depending on temps.

I think the new design motor is a constant run type. Along with the better motor design a continuous run would enhance lifetime. So long as the seal for the pump shaft doesn't start leaking this might be a lifetime of the car unit. (eg one of my cars now has 493,000+ & is at 21 yrs original engine)

Re: MECS Pump Lifetime
 

I didn't see any on/off control on the original pump. It's very simple structure, two pins come in from connector, then connect to two brushes and drive the motor.
And there is no shaft leak issue at least on the original pump, motor and pump blade are coupled by magnetic, they are completely separated.
I guess Dorman pump has much simpler structure(that's why it's so small), the pump blade is rotor and has magnetic on it, it must be separated from windings on the other side which act as stator. If that is the case, no leak issue as well.

Re: MECS Pump Lifetime
 

Motor on Bosch pump

Re: MECS Pump Lifetime
 

This is the other side, motor and blades are magnetically coupled

Re: MECS Pump Lifetime
 

thanks for sharing the photos. I still have the stock MECS pump at over 101,000 miles. I also carry the newer replacement pump in the vehicle.

Re: MECS Pump Lifetime
 

The on-off feature would be done elsewhere, not in the pump/motor itself.

The shaft seal thing I raised was about the new style pump, thinking that such might be the only issue for a very long life pump/motor.

This system doesn't need alot of flow, so a brushless DC motor can be quite small and low power.

So I was thinking that the new style may "run forever!"

I replaced my OEM pump/motor purely on spec since I had seen many entries about them failing at something above 50,000 miles.

Re: MECS Pump Lifetime
 

I did the same thing and my FEH seemed to go into EV mode more often afterwards.