01-17-2013, 05:34 PM
Join Date: Jun 2011
Location: Brisbane, Australia
My Ride: 2007 MX-5
| Well, a few test drives around the suburb this morning through all the streets and no problems. Covered 6 km of twisty bits now and it works like a bought one - leak checked all okay. The missus has taken the Bimmer to the shops now so there's confidence for you.
The reservoir started off slightly over filled but, after the first test run of 1.6 km, it was down to just touching the dip stick - close to taking in air again. So I reckon what happened on the failed attempt on 16 Jan was that the reservoir got very low and the system took in a gutfull of air that I couldn't remove.
I guess I got it out with yesterday's "extreme" flush i.e removal of pump and reservoir, fix pump, refit everything, refill, go slowly on the bleeding process (drink a few beers) and keep an eagle eye on the reservoir fluid level.
I won't be happy until we've covered a few hundred km. I'll keep the new pump just in case but it may be for sale at a bargain price in a few months.
1. Get the front wheels off the ground if you can prior to running the engine and initially exercise the steering wheel just a half turn each way s-l-o-w-l-y. I couldn't do that as the car was out in the carport on a 1:6 slope with the front wheels on 100 mm of wood so I could get under the front of the car- see pic. I recommend 150 mm elevation to get just a bit easier access. I couldn't put the car in the single garage (the only piece of flat ground for miles) because that's being repaired and painted after hail storms in December.
2. Check the fluid level in the reservoir frequently during the bleed process and just take it a little bit at a time. Be patient - something I'm not good at.
3. If you want to flush the system, don't be a pussy and mess around with turkey basters etc. Undo the two connections at the pump and drain the oil. Then plug the pump delivery line (rubber hose), remove the airbox (easy to do but plenty of DIYs out there), and remove the reservoir. Put a plastic sheet and lots of rags over the alternator when you do this - you don't want to replace the alternator at $$$ because it got filled with ATF do you? Wipe out the reservoir with lint free clean rag, put everything back on and do the bleeding process.
4. The BMW "only use once" hose clamps do not have to be broken off or cut off. You can just unclip them by using a thin blade screwdriver under the claw of the clip - see pic. Replace them with jubilee clamps and do not over tighten - you'll need three clamps (one for pump and two for the reservoir) if the car is original.