sjc246

I bought a complete set of the billet aluminum pulleys (a lot of places sell them, I'm not sure who actually makes them) for my E55. The set I received has identical pulleys for both belt tensioners (the two large smooth pulleys), however, the OEM pulleys are different sizes: the main belt tensioner pulley is thinner and a larger diameter. The image in the instructions as well as all of the pictures I find online appear to have two different size pulleys matching the stock sizes. I assumed I had received the wrong pulley and contacted the seller (fabtech), however, they have informed me that I am incorrect and that both pulleys should be the same size (unlike the factory pulleys and the appearance in the pictures). I believe (very strongly) that they are wrong and sent me the wrong pulley, but I wanted to confirm that with someone who has the same set before I make a big deal about it. So: should the aluminum tensioner pulleys be identical to eachother or should they be the same size as OEM?

Thanks for your help!

cmpcpro

I don't know but wouldn't think it would matter as it's just the smooth one so it's just there for tension and the tensioner will adjust to correct the difference.

sjc246

Anyone else?

Thanks for the response.

It might work, but if the pulley is, in fact, supposed to match the OE one, I'd rather not settle for something that might cause problems. I didn't actually run it, but I did bolt the pulley on the tensioner before I decided to keep it off for now. With a washer behind it, it didn't quite rub on the tensioner, but it is VERY close (because it's wider than the OE pulley). Also, because it's much smaller, I'm worried that the tensioner will be at or very near the end of its travel and will not adequately tension the belt (I didn't actually try it, though, so I could be wrong).

tw2

Is this the 5 pulley replacement set? I think UPD makes them. Here is the link to their website with a picture if it helps... http://ultimatepd.com/2003-2007-m113...idler-kit.html

I don't know which pulleys go where but it looks like there are two smooth pulleys the same size and a much smaller one.

tw2

And the link to shardul's set which I believe is UPD also https://mbworld.org/forums/e55-amg-w...idler-kit.html

shardul

iTrader: (1)

Both the tensioner idler pulleys are the same size in the after market it. The tensioner assemble for the accessory will accommodate for the different size.

MACEDON

That's why I didn't gamble on them and went with Shardul. I think they're manufactured by ASP? At any rate, top notch in the game. Hopefully he can chime in.

shardul

iTrader: (1)

Most of our items are made by ASP
We have exclusive on some of the items made by ASP that is why they have to bought through UPD

sjc246

Thanks, everyone, for the replies. My question has been thoroughly answered. I guess it was just the angle of the picture that made them look like different sizes to me.

tw2

Let us know how the install goes, I plan on picking up a set from Shardul in the next few months.

carguyshu

make sure you buy some spare bearings. mine are shot after only a couple thousand miles.

tw2

The new ones that came installed in the billet pulley kit? I assumed they used new oem ones?

carguyshu

they are new bearings in the pulleys & im not the only one who has had a problem with their longevity

MACEDON

Do you have a BWK? It can make things worse for those bearings.

They're nachi bearings, same stuff that goes on the SC pulley.

These cars are heavy duty, unfortunately they eat through a lot of resources.

carguyshu

i have a BWK, but am yet to install it. the double idler set should see no additional stress even if there was a BWK and those are the bearings that have gone bad on mine (I'm not sure if its the front idler, rear idler or both that's making the noise). I need to get the bearings swapped before something catastrophic occurs.

cmpcpro

Actually the double idler that is just a bolt going into the motor is now braced with a belt wrap kit so I'd say it's considerably stronger.

new55

same here.. bearing squeak - oem bearings are better but these actual pullies are nicer. i had a bwk on mine and took it off - i thought that may have caused premature wear on the bearing because the belt was an extremely tight fit - apparently they may be a lower nachi grade than really needed

MACEDON

That's not necessarily true. You're putting a lot more tension on the belt by wrapping it and eliminating most of the slip. The whole tensioner will see a lot more stress overall. As will the crank, AND the supercharger pulley.

Do understand that a mod like that will add a lot of variables to a system that was designed, tested, and manufactured with tolerances mandated by the manufacturer, anything we (the modders) do is guesswork.

I wonder if pulleys need re-sitting after installation, you put them in but heat expansion has a mind of its own and might throw things off balance- just speculating.

carguyshu

The double idler is on the left. The BWK pulley is on the right. Sure it is going to put a different load on the supercharger and crank pulley than the stock config, but its not going to change the load direction or amount on the double idler on the left. Even if it did it would only be putting stress on 1 of the 2 idler pulleys and not both since only one of those pulleys deals with the supercharger belt.

If you've installed them you would see there is nothing to reseat or nothing that can be changed once they are on there regardless of any expansion cycles. They are just crappy bearings that are put in the pulleys.

cmpcpro

Just the support bar connecting the double to the new one which is then connected to the new rear bracket on the motor has strengthened the double considerably.

carguyshu

i don't know about that. The bolt still goes through it and the bar connects to another bolt on another pulley that the way the belt is routed is pulling that bar the same direction that the tension is being put on the double idler. At best it is probably a push and it could be argued that this bar is actually hurting things since it is pulling the double idler even more the same direction the belt is putting pressure on it.

tw2

So what would you guys recommend - the billet set as is, new oem pulleys or billet set and then forking out even more for oem bearings? Some of my pulleys are rusty which is why I would like to replace them sometime.