Originally Posted by Senikc
I have a 99 Z3 2.5 liter 6cyl with 95000 miles, I have no history on the car, I am planning to replace the heater inlet pipe and water pipe (plastic parts) has anyone replaced them on the 6 cylinder...
At 95,000 miles, the whole cooling system should be replaced, not just those two plastic pipes. In accessing them, you have to remove so much. I have studied out replacing the cooling system on my Z3 1.9L, using RealOEM.com. You might do the same for your 2.5L, whose parts will be completely different. Put the last 7 of your VIN into RealOEM, save the link, and it will be easy to go back and navigate for your car. Here's my 1.9L. RealOEM gives typical prices and is not a store; BMW dealers are much higher, and stores like BMW South Atlanta and Bavarian Autosports will be less.
COOLING SYSTEM REBUILD Z3 1.9L
Brass bleeder screw Bav. Autosp. RBS 1
Coolant - dealer 82141467704 1
Fan shroud fasteners 17111712963 2
Radiator 17111728907 1
Gasket ring for temp. switch 32411093596 1
Radiator cap 17111742231 1
Expansion tank 17111712835 1
Gasket ring under exp. Tank 17211712965 1
Water Pump & Thermostat
Water pump 11510393338 1
O-ring for water pump 11511714519 1
Thermostat w/housing 11531743017 1
Axial gasket for thermostat 11531743179 1
Upper radiator hose - right 11531743535 1
Upper radiator hose - left 11531743295 1
Lower radiator hose 11531247261 1
Hose on top of plastic heater pipe 11531247398 1
Hose on end of plastic heater pipe 64218400295 1
Double hose on plastic @ rear head 11151247903 1
Plastic connector pipe on block 11531714738 1
O-ring for block connector 11531709157 1
Plastic Y connector on head 11531743679 1
O-ring for Y connector 11511739691 1
Lower intake manifold gasket 11611734684 1
Upper to lower intake man. gask. 11611247478 2
Block coolant drain crush ring 0 then 7119963200 1
EDIT: I don't know if a 6-cylinder even has the plastic connector on the rear of the head.
EDIT: RealOEM typical prices total to $800. A BMW dealer could be many times that, while online vendors will be less than that.