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97,000 kilometers on the first set (installed at 145,000 kilometers) and ~44,000 kilometers on the second set (installed at 242,000 kilometers).
I only run pulleys, bearings, and belts for a maximum of 60,000 miles, then replace whether needed or not. I tend to be preventive maintenance inclined rather that wait for a failure on the side of the road. I regularly take a road trip of 850 kilometers one-way and at one point the nearest Mercedes parts suppliers are literally 290 kilometers behind me and 290 kilometers in front of me. That would not be a good place to break down, especially during a winter ice storm (last one I made the mistake of driving in it took me 7 hours to cover 120 miles and I counted 27 vehicles in the ditches before I just gave up and sought shelter)
First set was a Dayco serpentine belt tensioner (89335) and Febi supercharger belt tensioner (36981). Serpentine belt idler pulley was a Febi 36931. Dayco supercharger idler pulley was a 89012 (should have used the 89130) plus the NSK 6203ZZC3.
Second set installed at 150K miles: serpentine belt using a Febi 15875 tensioner plus Febi 44977 idler pulley. Supercharger drive belt was a Dayco 89130 plus the 6203ZZC3 bearing in the idler pulley plus Febi 36981 tensioner pulley ($220 from FCP Euro).
Using the Dayco 89130 plus the new bearing only cost me about $25. I'll rework the supercharger idler pulley again at 338,000 km rather than spend hundreds of dollars on a replacement. Don't cheap out on the bearing; only go for a quality one as the $3 cheap bearings will throw out the grease within days.
I see no reason you cannot find a Febi equivalent to the Dayco 89130. Those specifications are:
-diameter 90mm
-width 26.2 mm
-flange yes
-belt width 6-rib
-bearing ID 17mm
In fact, going by these measurements i think the gates 38019 is the direct equivelent of the Dayco 89130
I replaced the complete febi unit on my SL55 last year, so trying to avoid spending another £200+ if possible. The plastic has now broken on the G55, so planning on rebuilding the old SL55 one which I kept.
I'm leaning towards just buying the metal one listed on amazon by ACDelco. Will replace the 6203ZZC3 bearings also. $50usd gamble.
Does anyone know how to separate the 2 pulleys?
The pulleys just slide apart off of the bolt and spacer. Be sure to photograph how it disassembles so you can ensure you put it back together correctly.
The pulleys just slide apart off of the bolt and spacer. Be sure to photograph how it disassembles so you can ensure you put it back together correctly.
Thanks. Stupid question, the bolt at the top seems to be attached to the same spindle (?), how do i loosen the bolt to separate the two pulleys?
There are only one bolt holding the double pulley? T50, I used a bit and a spanner due to lack of space. Once of there are nothing holding them together so you just pull them apart.
Download the .pdf attachment in the first post. It has photos of disassembly.
So I managed to pull it apart and knock the bearing out. However my bearing seems to be slightly wider than the ones recommended in the thread
(Left the one mentioned in this thread, right the existing bearing)
Using the inspiration of the thread starter @bbirdwell on replacing the bearing on the Super Charger (SC) double idler pulley and buying an aftermarket regular pulley for the second pulley of that double, I recently replaced all my pulley’s – idlers and tensioners, on my 60K mile 55 as follows. In update I did not repeat everything already posted in the thread, but have added what more I did. I hope this is helpful.
The approach I have assumed is that both tensioners are in good shape and all that is needed is an update to the pulley bearings. You should make sure the tensioner has a consistent tension as you lever it through its arc of range. Any noise, catches, roughness, or change in the smoothness of the arc is reason to replace the entire tensioner.
The engine has two serpentine belts - a regular belt that drives the alternator, A/C compressor, PS pump, and all the other components except the SC. The SC belt only drives the SC. That belt is wider than the typical and the regular serpentine belt.
The current cost of the tensioners and idlers from MB is more than $1,400. If you order them from a MB online dealer you can get that cost down by about 25% or so (down to about $1,100). Aftermarket components are a much lower cost option and if you follow these steps you can keep the cost below $75.
There are two tensioners. The regular belt tension has a plastic pulley so replacing the bearing in that pulley is not an option as the bearing is made into the pulley. But, that pulley is separately available.
The SC tensioner pulley was not readily available after a search. This pulley is steel and of a clam shell design. It has two halves with the bearing sandwiched between the halves. Machine rivets hold the two halves together and relatively easy to grind off the rivet protrusion (there are five rivets), once grind off drive the rivet out of the mounting hole, and then the two halves can be separated. Tap the bearing out and slide the new bearing in (use the heat/freeze method if need be). I used 5mm diameter x 10mm length class 10.9 allen head screws with nylon lock nuts torque to 120 in-lb to put the two halves back together.
Here is the breakdown of each pulley/bearing/hardware used. Bearings were sourced on eBay, pulleys on RockAuto, and the hardware locally.
We also have all the idlers in billet with "Nachi bearings in stock at all times. Black anodized or silver. Some of the OEM idlers are one time press style only, that means if plastic, the tolerances do no bode well with a second bearing press. Also as you can see by the knurling on the oem SC bearing posted above, this can also make a second bearing press less stable. Just depends if you are looking for a quick fix or long term sleep well at night fix. http://ultimatepd.com/2003-2007-m113...r-kit-179.html
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E63 Biturbo, UPD Cold Air induction kit, UPD performance crank pulley and UPD adjustable rear suspension with ride height adjustment.
Using the inspiration of the thread starter @bbirdwell on replacing the bearing on the Super Charger (SC) double idler pulley and buying an aftermarket regular pulley for the second pulley of that double, I recently replaced all my pulley’s – idlers and tensioners, on my 60K mile 55 as follows. In update I did not repeat everything already posted in the thread, but have added what more I did. I hope this is helpful.
The approach I have assumed is that both tensioners are in good shape and all that is needed is an update to the pulley bearings. You should make sure the tensioner has a consistent tension as you lever it through its arc of range. Any noise, catches, roughness, or change in the smoothness of the arc is reason to replace the entire tensioner.
The engine has two serpentine belts - a regular belt that drives the alternator, A/C compressor, PS pump, and all the other components except the SC. The SC belt only drives the SC. That belt is wider than the typical and the regular serpentine belt.
The current cost of the tensioners and idlers from MB is more than $1,400. If you order them from a MB online dealer you can get that cost down by about 25% or so (down to about $1,100). Aftermarket components are a much lower cost option and if you follow these steps you can keep the cost below $75.
There are two tensioners. The regular belt tension has a plastic pulley so replacing the bearing in that pulley is not an option as the bearing is made into the pulley. But, that pulley is separately available.
The SC tensioner pulley was not readily available after a search. This pulley is steel and of a clam shell design. It has two halves with the bearing sandwiched between the halves. Machine rivets hold the two halves together and relatively easy to grind off the rivet protrusion (there are five rivets), once grind off drive the rivet out of the mounting hole, and then the two halves can be separated. Tap the bearing out and slide the new bearing in (use the heat/freeze method if need be). I used 5mm diameter x 10mm length class 10.9 allen head screws with nylon lock nuts torque to 120 in-lb to put the two halves back together.
Here is the breakdown of each pulley/bearing/hardware used. Bearings were sourced on eBay, pulleys on RockAuto, and the hardware locally.
Formatting of the above chart failed so PDF file attached.
Thanks, I have replaced the serpentine tensioner with the Uro part despite people bashing the brand. They used an NTN bearing so it should be okay. I have also bought an idler pulley from Autozone, and ordered the other Dayco tensioner which I will install when it arrives. There is a Vaico part that you could order instead of 1122000970P which is V300237 but it costs about $15.00 more.
Is the torque spec on the idler pulleys bolt really 68Nm? Seems a bit high
Straight out of WIS. Seemed high to me also and it is a PITA to put a torque wrench on it. Do what you can. Personally, I was afraid I was going to strip out the threads...
If in doubt, use thread lock but reduce torque a bit to account for the lubricity of the liquid thread lock. FWIW and I am not a professional mechanic; just an amateur wrench turner.
Most the idler bolts are really hard to get an accurate torque on for the DYI er. Bolt heads may have been worn over the last 15 plus years (changing TQ accuracy of wrench) and if you do not have a recently calibrated wrench, then things can go wrong. If you have turned a few wrenches over the years, then going by feel and blue locktight works for most. *
When torquing, you do need a quality wrench, calibrated and no extensions can be used either.
When torquing, you do need a quality wrench, calibrated and no extensions can be used either.
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E63 Biturbo, UPD Cold Air induction kit, UPD performance crank pulley and UPD adjustable rear suspension with ride height adjustment.
06-08-2020, 06:10 PM
