notes on 2003 VANOS change

Allan in Athens

New member
Used the pry bar on the water pump to pry the sheetmetal crossmember about 3mm and the VANOS rotated and slipped right out. I also loosened the 4 bolts on that crossmember before prying.

- I got oil all over the top of the engine despite furiously dobbing with 6 cotton t-shirts as rags. Got oil and coolant on my belts- but it didn't seem to hurt them.

- on my '03 Z4, I had to disconnect the lower radiator hose and it's 2 electrical connectors to allow the VANOS clearance.

-I had to remove my windshield washer tank to allow access to the solenoid electrical connectors.

- the thin metal gaskets on the VANOS will cut you.

-one of the 10mm nuts holding the VANOS on is above/next to the thermostat. If you don't have magnetic sockets, use a dab of RTV or form-a-gasket on the nut so that it sticks in the socket and doesn't fall down into the engine. It takes several tries to get that nut back on to that stud.




I followed and used this as a guide:

"I've done more than 30 VANOS and several were Z4 (I'm helping Beisan System here in the west cost and helping with the launch of the products in Italy). The bigger problem with Z4 is the clearance between the VANOS unit and the front cross member. The TIS is useless: information are generic and gives little insight on how to do it on the Z4 (as a matter of fact is the same exact procedure regardless the car). The Beisan procedure is far better: http://www.beisansystems.com/procedu..._procedure.htm

Some advice.
1) you'll need a pry bar similar to this one Harbor Freight Pry Bar



Once you're ready to remove the VANOS unit, remove the 4 bolts on top of the cross memeber, put the pry bar on the waterpump shaft and push back on the cross member while you remove the VANOS from the studds. I find it best to have someone helping. I also have pix at home on how to do this. I just moved and I'm not sure I'll be able to upload them tonight, but I'll try.

2) you'll need a 90 deg angle long nose pliers to remove the orange caps in front of the bearing. The straight pliers won't fit.

3) between the nuts #1 and #2 from the right (facing the engine) holding the VANOS to the head there's a bolt holding the thermostat. Since you won't see what you're turning, pay particular attention.

4) On earlyer Z4 the temp sensor is at the exit of the thermostat and will be in your way of removing the VANOS: you'll have to remove the upper connection (connected to the thermostat) of the lower coolant hose. Some coolant will drip out, but won't bee to bad. If that's the case for you, make sure you check the coolant level, fill it up, and blead it.

3) when removing the 2 caps in front of the VANOS piston (8mm allen) you'll need a traditional 8mm 90 deg allen wrench and you'll have to use an pipe to break it loose. A torque wrench won't fit there.

None of this is on the TIS: in some sections it actually assumes you have the engine removed form the car. It also say you need to lock the timing: this IS NOT necessary on double VANOS cars and timing WILL NOT be affected."

Allan
 
wow... this is a soon to be done task for me on my 03 so I thanks for the words of experience! I'm not looking forward to it - I was going to drop the engine a little is there a reason you tried to pry instead?
 
So today was my day to do my vanos on my 2003 3.0. I wanted to reply incase anyone in the future has a go.
Couple of things, firstly it wasn't that messy, I had a towel and my vacuum pump on hand for drips but there wasn't a lot. My vanos seals were hard as anything after the 100k on my engine.

But the main thing was my vanos unit came straight out, no bolts undone or moving of anything, it just tilted out. so was a lot easier!
 
Just a follow up incase anyone searches. I did my vanos and then did a 1300 miles round trip around Scotland. My average mpg was 34... I had some sedate 50mph but then also did give chase to the gumball 3000 Z4 at one point which might have been at speeds over 65mph.... before I did my vanos I didn't get anything over 30 no matter how I drove.
It certainly makes a massive difference!
 
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