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GLK250 bad alternator. Does it sound like small brake squeal?
Had the big red battery icon popup on the dash, 10 minutes prior I noticed what sounded like very quiet brake squealing from the outside (when no brakes applied) from the passenger side. Is this the sound of bad alternator bearing? Can the voltage regulator be checked without alternator removal?
Don't know how else to describe the sound. Mercedes OEM battery replaced last year, the AUX battery (GLK250) is 9 years old so it could also be that. But would have expected an AUX battery warning.
My 13 glk 70000 miles started charging poorly. Voltage would drop. I only noticed it using a CTEK remote battery monitor and app.
Everyone told me to replace the alternator. But the cheapest are about 600 and up to 1100$ . I read the alternators last and last but the regulators go bad as brushes wear out at 110,000m. So i decided on a new set of brushes. You have to remove the alternator to change them. The way the brushes Release I would not take it apart to check the brushes. They extend to set position when installing them automatically.
The new regulator brushes fixed everything.
The old brushes were below minimum recommended length at only 70,000 miles!
New brushes and an hour work fixed it. You should polish the commutator when doing this . Use 400g sand paper cloth, I had a friend hold the alternator while spinning it with a drill and I used the 400g to clean the commutator. 600 g will work and maybe 200g but it might not be smooth.
FCP euro sells brushes for around 125$ with lifetime warranty. Charge and check your battery and get it tested first . They can be defective. You do have an AGM ?
My 13 glk 70000 miles started charging poorly. Voltage would drop. I only noticed it using a CTEK remote battery monitor and app.
Everyone told me to replace the alternator. But the cheapest are about 600 and up to 1100$ . I read the alternators last and last but the regulators go bad as brushes wear out at 110,000m. So i decided on a new set of brushes. You have to remove the alternator to change them. The way the brushes Release I would not take it apart to check the brushes. They extend to set position when installing them automatically.
The new regulator brushes fixed everything.
The old brushes were below minimum recommended length at only 70,000 miles!
New brushes and an hour work fixed it. You should polish the commutator when doing this . Use 400g sand paper cloth, I had a friend hold the alternator while spinning it with a drill and I used the 400g to clean the commutator. 600 g will work and maybe 200g but it might not be smooth.
FCP euro sells brushes for around 125$ with lifetime warranty. Charge and check your battery and get it tested first . They can be defective. You do have an AGM ?
Thanks! I bought the battery from the dealer so i assume its AGM. I'll have the garage(indy) check the brushes, but I suspect they'll try and push an alternator replacement
Before you buy a new alternator (or even brushes), spend a few (literally) bucks and get a mechanic's stethoscope. With that, you can probe the suspects and find out what's really making the noise. The cheap tool is by far the best method for finding odd mechanical noises in your engine compartment.
And FWIW, I suppose you COULD spend a whole lot on a new alternator, but quality rebuilts aren't all that spendy. Here's the selection (YMMV) for my car from RockAuto (just as a reference). Might be a lot easier than just swapping brushes.
to follow up (incase someone has similar issue). The mechanic says it's a bad negative wire which needs replacing. approx $500. That wire must be made of gold
they charged 180 for diagnosing the issue. Fair since they had to hunt for the root cause of a bad cable (not obvious)
cable was 150. Its the cable from the battery to alternator, there is a sensor in the cable which failed
180 for installing the cable. Fair enough.
they wanted $350 to top off the DEF. hell no! thats more than a dealership for pouring a bottle
GLK350 2010 Sold C63 AMG 2012 Sedan Sold GLK250 2013
Has anyone tried to swap the alternator. I’m trying to do this now and can’t find a write up. It seems like there is a significant difference between the GLK250 and GLK350. There is way more things in the way. Any help tips would be appreciated. Did you guys do it from the top or bottom. How much stuff did you have to take apart to do this.
Has anyone tried to swap the alternator. I’m trying to do this now and can’t find a write up. It seems like there is a significant difference between the GLK250 and GLK350. There is way more things in the way. Any help tips would be appreciated. Did you guys do it from the top or bottom. How much stuff did you have to take apart to do this.
Did you solve your problem? I too need to change the alternator and there are hardly any guides online for the 250
GLK350 2010 Sold C63 AMG 2012 Sedan Sold GLK250 2013
I tried to do it myself and found it to be too difficult. I took it to my mechanic and i think the book time for it was under 3 hours. The mechanic said it took him well over 3 hours. he had to lower the sub frame to get access to the lower bolts. He still charged me the quoted book time but said he will not agree to charge the book time for the next customers lol. FYI he is a Mercedes mechanic. It wasn't worth it for me to try to figure this out without a lift.
What year, I’m no mechanic but my friend who is, he and I took out my alternator and swapped out the regulator and polished the commutator in an hour with a Beer , ( I was the one with the beer ) I have a 13, no lift , all easy
What year, I’m no mechanic but my friend who is, he and I took out my alternator and swapped out the regulator and polished the commutator in an hour with a Beer , ( I was the one with the beer ) I have a 13, no lift , all easy
I See your profile says you drive a 350. I believe the previous poster has a 250 like me.
I'm devastated to hear it could be very difficult.
Can anyone tell me what voltage regulator I need to order? It seems the 13 glk250 may have had a different alternator than the 14
Not sure of your exact vin so I looked up GLK 250 204.936 and it shows two different alternators, a 150a and 175a.
I bought an inexpensive battery monitor that is useful for seeing the battery voltage in real time when driving around. The Ancel BM200. Its wireless thru an app to use on a phone. I dont think it is reliable for checking battery health or state of charge since you cant input which specific battery its being used on, unlike my other battery tester where you can input what type battery it is and the amps. But for seeing voltage its good, see what the car is doing while driving, at stop lights etc.
Just today, I used my own el-cheapo battery tester to check the health of my battery (one that came with the car, so it's kind of an unknown). It measured north of 75%, so I'm OK with leaving it for a (hopefully much) later replacement.
I also just swapped out my alternator, having seen a couple slightly concerning episodes where the "engine running voltage" dropped to just over 12 volts for no apparent reason. With over 170,000 miles, I just consider that preventative maintenance - something I'd have to do before I finally move onto my next daily driver (hopefully 100,000+ miles from now). I should add that swapping the alternator on a GLK 350 (M272 motor) is a relative breeze, with the one slightly stinky wrinkle of having the drain the cooling system to move the hose that's in the way (hey, most of us are due for a cooling system refresh anyway!).
I do monitor my battery / alternator voltage regularly, and easily using a cheap and necessary (as a USB charger) device: - a whopping $7.19 delivered... I just checked it today, and its voltage reading agreed exactly with my OBD breakout box and "good meter". Barring heavy loads on the USB ports, that makes sense...
The 250's alternator is absolutely buried. The mechanic's instructions are you remove the strut and rack in pinion steering among all the other houses, heat shields etc. I'm trying to avoid
that.
I've taken out the rad fan, belt, coolant and intercooler house. Had to remove the brackets under the steering rack to drop it in order to squeeze my small hands in tight spots. I just have the writing to remove before the alternator will slide out but I didn't recommend this job to anyone without a lift and mechanical know-how. I'm in over my head and not sure yet how I'm going to line up things going back in.
My hat's off to you, Adam... sometimes the only way to get more experience is to work yourself into a position where there's just no other viable option! ;-)
Sorry to hear that the GLK 250 is such a bear - you'd tend to think it should be easier (smaller engine) but then again, "turbo". I guess there's no way to wrangle the regulator off the back and swap it out without removing the entire alternator (then again, if you swap the alternator today and one of the main bearings goes next week, you're going to be hating life).
Is it a situation where dropping the front (engine / transmission) subframe a few inches would help?
Is it a situation where dropping the front (engine / transmission) subframe a few inches would help?
Cheers. There is no hope of changing the regulator in the vehicle . Progress is slow with so much happening in my life ATM. But I did just get it out. We'll see how the install goes..
Anyone know how to source an appropriate regulator?
Valeo 180a.
A0141543902
'13 Glk250 alternator removal without removing strut or steering rack. Difficulty high due to blind and tight access to bolts.
GLK350 2010 Sold C63 AMG 2012 Sedan Sold GLK250 2013
I found that everyone had this on heavy back order. I had ordered mine from the dealership. I had to wait 2 weeks for it to come from Germany. Seems like they keep pushing for alternator swaps rather than the regulator. Replacing the regulator totally work for me and my alternator is still in good shape. My GLK has 280,000 km.
02-12-2023, 07:34 AM
. Progress is slow with so much happening in my life ATM. But I did just get it out. We'll see how the install goes..
