air pump rebuild
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c32 amg
air pump rebuild
after the air pump melted down on my brothers c320 Ive decided to rebuild the pump on my c32 before it melts. Its just a basic DC motor. Replaceing the brushes,bearings and cleaning the commutator should do the trick. Ill post the brush and bearing part #s .Any motor shop can crossreference and order these parts .Cost should be less than 50.00 .Should be a simple job and save major bucks.
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C55 AMG, 300D-T & Karmann Ghia
dead on as far as I know. A lot of people have issues with them; anything from a shrill noise to a complete meltdown-literally!
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2002 C32, 2012 S550
From my experience, the main reason the Secondary air pumps melt down is because the relays that activate them get stuck ON, thus never turn off even when you leave the car.
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c32 amg
thanks for the info on the relays.The contacts are probably welding themselves shut. Ive heard these pumps draw more than 30 amps, so they play hell on the contacts. Do you know where the relays are located? Ill definitely inspect and replace the relays if needed when I rebuild the pump motor. thanks again for the info
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From: New Zealand
Thanks for the info, sounds overly complicated. I don't think I have had a car with this sort of system before. Luckily here there is no emissions testing, you can pull out whatever emisions equipment you like including the cats, not that I would do this, I would hate to think what errors would come up.
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10 C six trizzle
spot on. The newer cars (direct injection v6's) secondary air systems use 2 relays, one is the normal style the other is solid state which prevents this from happening. Very rarely do the pumps just fail, but like any part they will wear out over time, but 95% of the time the relay sticks and melts them.
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c32 amg
I agree,no telling what codes the car would throw if you deleted the pump. I removed the two secondary cats but left the resonator on the car. The car passes emissions tests in Virginia and North Carolina with two cats and air injection.
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c32 amg
My c32 is an 03. I don't know if it has a mechanical or solid state relay. Ill probably just check brush wear in the pump motor and if OK leave it alone. Iwill convert the pump circuit over to a 12 vdc solid state relay capable of carrying the amperage. thanks for the info
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From: OC
C32
I agree with the crowd on the relay is the real issue. I say just change the relay every 30 k or so and be done with it.
I bought a couple of relays off Digikey like 5 years ago and replaced one of mine. They were like $7 but I had to pull the plastic cover off the relay and change the parallel resistor across the coil. The value in the Benz p/n relay is not available to order with the relay. It might be possible the parallel resistor is not all that critical but thought why take a chance when the $2000 ECU is driving it.
Not sure all the work was worth saving the few bucks.
I bought a couple of relays off Digikey like 5 years ago and replaced one of mine. They were like $7 but I had to pull the plastic cover off the relay and change the parallel resistor across the coil. The value in the Benz p/n relay is not available to order with the relay. It might be possible the parallel resistor is not all that critical but thought why take a chance when the $2000 ECU is driving it.
Not sure all the work was worth saving the few bucks.
