Evosport Under-Drive Pulley Installation

[ELEVENS]

EVOSPORT UNDER-DRIVE PULLEY INSTALLATION ON 2003 BMW M5

DISCLAIMER: Use these instructions at your own risk, they are informational ONLY. I make no claim to their accuracy or how it might be different on your car. Do not attempt the install if you are not a very good mechanic and have proper tools. Please be safe, as working with tools and a motor can be very dangerous! I will not be responsible for any injury or property damage that might result.

Do this with a COLD engine. You will be reaching down in front of the engine A LOT, and the fan shroud is very sharp. Do your forearms a favor and put two layers of masking tape on the edge of the fan shroud.

TOOLS:
32mm open-end wrench or adjustable wrench
screwdriver
10mm, 13mm, 15mm sockets (3/8" drive)
T50 Torx socket (3/8" drive)
15mm and 24mm sockets (½" drive)
air-driven ratchet will speed things up considerably, but not required
2 ½ pound hammer
Blue LocTite
Die grinder with carbide burr, Dremmel tool, or files
3/8" ratchet wrenches and ½" drive breaker bar


Background: The coolant system remains sealed. The Air Conditioner pulley and it’s belt on the left side (facing front of engine) remains stock. Be careful not to nick the radiator with tools or parts. If you nick the radiator fins, use a tiny screwdriver and/or tweezers to realign the delicate fins.



1) Remove the MAF sensor electrical connectors (both sides).

2) Loosen the hose clamps at the intake plenum (both sides).

3) Unclasp the four stainless clips on the airbox lid(both sides).

4) Remove the ducting with airbox cover attached (both sides).

5) Stuff a CLEAN rag into the intake plenum openings or tape openings closed.

6) Using a 32mm open-end wrench (I used a big adjustable (Cresent) wrench, WHACK the
wrench handle to the right (left hand threads!). Mine popped loose easily.
7) Unscrew the fan (Righty-:Loosey), holding onto it at all times to prevent it from falling into the radiator and bending the delicate fins on the radiator.

8) Lift the fan out from the top.

9) DRAW A PICTURE or take a photograph of the drive belt routing before removal! If I had done that, it would have saved me 30 minutes. It’s not that easy to figure out.

10) Using sockets, loosen three 13mm bolts from power steering pulley, four 10mm bolts from water pump pulley, six 13mm bolts from crank pulley. The big nut in the center of the crank pulley is there only for turning the crankshaft, it does not and cannot be loosened.

11) Using the 15/16" socket, remove the nut from the alternator pulley. It has a wave washer behind it. There are at least two ways:
a. Remove the radiator and use an impact wrench
b. Use a 24mm 1/2"-drive socket on the nut, and hold it with a pipe wrench. Now go through the center of the socket with a T55 Torx bit on a 1/4" wrench to turn the alternator shaft while holding the big socket stationary h the pipe wrench.

12) Relieve tension on the belt by turning the tensioner pulley bolt to the right using the breaker bar w/ 15mm socket. Remove the belt.

13) Loosen the A/C belt using the same strategy.

14) Remove pulleys: water pump, power steering, crank, alternator.

15) Remove the pulley tensioner with the T50 Torx (under a pop-off plastic cover on the pulley, and the zinc/cadmium-plated 13mm nut and washer.

16) Remove both tensioner pulleys and grind the tensioner bracket per Evosport instructions. This is a trial-and-error process. The Evosport tensioner pulleys go on with the deep dish (lip) facing away from the motor. Test the final fit by tightening the 15mm bolt on the new tensioner pulley BEFORE putting it back on the car. MAKE SURE THE PULLEY IS NOT BINDING.

17) Reinstall the water pump, power steering, crank pulleys onto the car using LocTite on all fasteners.

18) Reinstall the A/C belt.

19) Check the Evosport alternator washer for fit onto the alternator shaft. Mine had a too-small center hole, and also was far too thin to work properly. The washer should be able to slide all the way onto the shaft, not just over the threaded area. What will happen is after tightening the nut, the pulley will move fore/aft 1/4"! - not good! Once you get the correct washer(s), tighten the nut down using LocTite using the same procedure as #11 above.

20) Now put the tensioner bracket with pulleys back on the car. It’s a tight fit between the lower tensioner pulley and the power steering pulley, you will have to use a lever to move the tensioner.

21) Reinstall the belt, making sure all groves are lined up properly on every PULLEY.

22) Remove the tape from the fan shroud.

23) Remove rags or tape from intake plenum opening (both sides).

24) Double check everything, then start the car to check that everything is OK.

25) Once convinced all is well, reinstall fan.

26) Reassemble the intake ducting and MAF connectors.

[TJB]

How Long does it take to do this whole process. I currently have my engine out and am wodering if it is worth the time and effort even with the engine out. It is out because I am painting the engine compartment.

cheers,
Tom

[Ag02M5]

Hey do you still have the instructions by chance? I picked up a set without. Would be appreciated if you could scan a copy.

Thanks.

Ryan

[TiSiBeast]

Was there a noticeable performance inncrease with this mod?