slk32amg coolant pump

[purenrg]

I have been on a long drive over the easter weekend in my slk32amg and its started to display the coolant pump problem, just revs and reduced power surge. I had the same problem with the car 7 years ago and got a pump replacement from Mercedes and it has lasted approx 30,000 miles. I have checked the fuses and it has blown fuse 23 which is the fuse for the pump. My question is has anyone had any experience of using an ATV chargecooler pump as a replacement for factory part? The pump is an upgraded Bosch pump and is at least 50% cheaper than the price I paid for other pump.

Mike.

[SLacKer]

Is the fuse 5 amp? If so swap for a 7.5 amp fuse as fitted to the C32 and give it another go.

[slk 32]

I used a Johnson CM30 Marine pump. these have an increased flow rate and are a lot more reliable than the Bosch which tends to break down as the plastic impeller degrades

you can pick one up from a specialist for around £120-£130 ( avoid the e bay ones referring to mercedes - even though these are genuine Johnson ones they do tend to charge a premium)

Edited by slk 32 on Tuesday 2nd April 13:15

[purenrg]

Thank you for your comments I have fitted fuse and will try for warp speed in the morning and if no luck will go for the pump as recommended.

mike.

[slk 32]

No worries- let me know how you get on- I have a spare pump you can test with if necessary

[purenrg]

Good news for me, the car is going like a rocket and the 7.5 amp fuse seems to have done the trick. I would like to thank you both for the excellent advice and kind offer. I have located a Johnson SC30 pump from Mack Engineering in Glasgow circa £160 inc vat and postage so if the pump does go I will get one. Looking forward to another good blast at the weekend!

thanks again

Mike.

[slk 32]

Can't fault Mack engineering- that's where I got mine from - they seem surprised when I mentioned that it was going in a a car though!