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FCP Euro Service Kits

FCP Euro Kits

This morning my BMW X5 3.0i was making a rattling noise with a light screech from the engine bay. The outside temp gauge read 23 degrees fahrenheit and as my engine started, so did the noise. My car has the updated style hydraulic drive belt (alternator) tensioner installed from the factory, but with 80,000 miles it isn't sounding very good anymore. Time for some new parts.

It is likely to have a worn bearing

The common suspects of this noise are the belt tensioner hydraulic piston, tensioner pulley, and deflection (idler) pulley. You can get a tensioner repair kit or replace parts individually. Me? I like to tackle everything at once. I highly recommend replacement of the belt while you are in there as well. Once the tensioner starts making noise it is likely to have a worn bearing, and when the bearing wears it will cause the belt to rub into the pulleys and begin to wear the edges. Worn edges increase noise and shorten the life of the belt. If that happens you may be left stranded when the belt snaps.

m54 hydraulic belt tensionerWhat if your BMW doesn't have the updated hydraulic tensioner installed? You're in luck - the updated kit can be retrofitted to the following vehicles:

  • E39 5-Series
  • E36 Z3
  • E60 5-Series
  • E83 X3,
  • E53 X5 (to 5/04)
  • E46 3-Series (to 5/04)

 

Upgrade/Replacement Instructions:

  • open-uri20141003-14657-1vpn3np.Remove the reverse-threaded fan clutch from the water pump (AT only)
    • (Use fan clutch tool or 32mm socket)
  • Remove the engine fan shroud and pull the fan clutch up with it
    • If the fan clutch is leaking hydraulic fluid it should be replaced to prevent an overheat situation
  • Remove the A/C belt, rotate the tensioner clockwise, and pull the belt off
  • Remove the drive (alternator) belt, rotate the tensioner clockwise, and pull the belt off
    • This is a great time to check the water pump for play. Grab the threaded portion in front of the pulley and pull up and down. If it moves, it's junk. If it doesn't, then try spinning the water pump pulley. If you feel any resistance, it's time for a new one.
    • Spin the pulleys with the belt off. Audible grinding noises or ahigh pitched whistle indicate bearing failure. Replace.
  • Remove the upper deflection pulley 16mm bolt
  • Remove the two 13mm bolts from the mechanical drive belt tensioner and remove it. There will be three 13mm bolts if you have the hydraulic style.
  • Place the new hydraulic tensioner on the engine. It is held in place by 3 bolts and washers. Upper bolt #11 w/washer #12, lower bolt #10 w/washer #12 and left side bolt #13 w/washer #14
  • Now install the pulley (#6) placing the mud washer (#20) between the tensioner face and pulley with mud washer dish portion frontwards, then bolt (#7) the pulley to tensioner.
  • Install the upper deflection pulley.
  • Install the drive belt, A/C belt, fan shroud and fan clutch.
  • Tighten the fan clutch (reverse thread).

 

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Written by :
Jerry Sarno

Jerry is a Master BMW technician from Boston, MA with 10 years of automotive experience. He currently owns a BMW X5 3.0i, 540i, and a bass boat. During the week he spends his time in the shop fixing BMWs and likes fresh water fishing on the weekends.


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