Bleed problems? This is the factory fix:

[genphreak]

People this is an M60 thermostat

For those that don't know the M60 is the v8 engine,
introduced after the M20, M30 and M50 in-line 6 cyl engines were well into in production.

Notice the eyelet with the hole in it hole through it at the top of the flange near the seal seat?

It allows air to escape from the engine's head/s to the cavity where the bleeder screw is located when the engine is cold, making for easier bleeding.

Otherwise you have to wait for the head to heat up and the thermostat to open. The hole does allow coolant to dribble through at other times, but very very slowly, so does not prevent operation of the thermostat to any extent worth considering.

This is perhaps why we should all be drilling the 1/8" hole here before we install our thermostats- ie that BMW realised this themselves a bit later on? I think this is why its known as the dealer mechanic's shortcut when working on our engines.

Drilling the hole worked a treat for me. I found that enough air was trapped behind the thermostat and thus the thermostat took a little longer to open than it normally would (heat does not transfer through air as well as it does through liquid) so it made for dramatic bleeding and more warmth on the engine than I expected- this would upset other novices who expect their work to be wrong and not like to see anything that looks like a too-hot condition (not that it was) directly after it and during a bleed procedure.

[Alexlind123]

Maybe i just got lucky, but i had absolutely no problems bleeding. I didnt even have to open the bleed screw for longer than 10 seconds. I did massage the upper rad hose first to release alot of air into the expansion tank. ...maybe try that next time?

[gmannino]

Bleeding can be a real pain in the ass tho. I also second the hole in the thermostat trick. Logically it makes sense.

[genphreak]

Maybe i just got lucky, but i had absolutely no problems bleeding. I didnt even have to open the bleed screw for longer than 10 seconds. I did massage the upper rad hose first to release alot of air into the expansion tank. ...maybe try that next time?

I'll be sure to give it a shot, thanks. But I think I have done it. For me it is always the air lock behing the theermostat that causes the problem.

However it seems to be different for different people and different engines; which is why it is a constant topic of consternation on the board.

My guess is if you follow the right factory flush and fill procedure (by the TIS) or happen to stumble on a similar method when you do it, it can work out to be easier... maybe Nick

[Alexlind123]

I'll be sure to give it a shot, thanks. But I think I have done it. For me it is always the air lock behing the theermostat that causes the problem.

However it seems to be different for different people and different engines; which is why it is a constant topic of consternation on the board.

My guess is if you follow the right factory flush and fill procedure (by the TIS) or happen to stumble on a similar method when you do it, it can work out to be easier... maybe Nick

I followed the method exactly, except for squeezing the air from out of rad hose. It took me maybe 4 minutes total to bleed the cooling system, and it sitll performs flawlessly~no air pockets.