The UNOFFICIAL Brass Bleeder Screw Thread

This one's for you Bluebee. I could elaborate here but it's mostly self explanatory. Had a bleeder screw fail completely last week. Ordered these from OEMBimmerparts.com and installed today. Took about 2 minutes. Cheers!

From 2011-06-04

From 2011-06-04

From 2011-06-04

From 2011-06-04

From 2011-06-04

From 2011-06-04

From 2011-06-04

From 2011-06-04

From 2011-06-04

niceeeeeeee................but on hindsight...now that the bleeder screw is strong-er....wouldn't there be a possibiity of the PLASTIC threads on the radiator side stripping?then we'd have to make brass radiators....brass thermostat housing....brass etc etc........and finally a car made of brass.....oh those german engineers.......!

LOL yeah my indy said the same. This one is surely up for debate but I can at least sleep easy knowing my bleeder screws aren't going to fail.

I also have the brass bleeder screws. I ordered them to get free shipping on AutohouseAZ on $50+ orders, they are much stronger then the plastic ones, but then again I do not consider them an upgrade to the weak system.

As long as you don't over tighten the brass screw you won't damage the threads in the plastic. Don't know if there is a torque setting for the screw (don't really care). I just turn it until the screw just starts to compress the o-ring then another 1/4 turn.

Glad you are happy with them Mack

Thank you for your order.
Max

Just ordered a pair for my ride too. Going to be heading up Mt. Washington this weekend with few fellow Bimmer pilots and bleeder screw failure is not an option.

Originally Posted by Mack

Had a bleeder screw fail completely last week. Ordered these from OEMBimmerparts.com and installed today

This is so nice, succinct, and self-explanatory, that I say we make this thread the 'official' canonical thread on the brass bleeder screws.

That means we refer others to here for reference. And we cross reference back here with new information, over time.

Note: The intent is, for every topic, to have a 'canonical' thread to refer others to.

Which thread is canonical doesn't really matter ... you choose the thread as a good starting point - and then you make it canonical by adding the cross-linked data to it such as these (which were in that other thread):
- Post #124 in the alternator thread where the bleed screw broke
- E39 (1997 - 2003) > Broken bleed screw culprit
- E39 (1997 - 2003) > Cooling system Bleed screw locations 540i?
- Bleed Screw Busted...
- $4 brass bleeder screws
- E39 OVERHEAT... leaking from screws
- Leaking bleeder screws
etc.

BTW, one thing you've confirmed with those pretty pictures is that the length (i.e., the bite) appears to be the same (so that contention by someone that the brass 'bites' better, isn't apparently true).

As a start, I'll put this thread in the bestlinks along with the one that is already there for the brass bleeder screw:

- How to retrofit brass bleeder screws (1) (2)

Here is the complete sentence on the cooling system, to date:
- What to look for when your KTMP (1) or coolant temperature gauge indicates overheating (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) & what to look for in a perfectly normal E39 cooling system (1) & a picture of every failed part in the cooling system (1) & various techniques to properly bleed (1) (2) (3) & refill (1) & drain (1) (2) & flush (1) & what coolant to use (1) & what parts to replace (1) (2) & how to retrofit brass bleeder screws (1) (2) & what special tools to make or buy (1) & how to tell how old your cooling system is (1) (2) & how to test the cooling system auxiliary electrical fan (1) (2) (3) (4) & a DIY for replacing the auxilliary fan (1) (2) (3) & the infamous fuse 75 (1) & the aux fan relay (1) & how to diagnose lack of HVAC/IHKA heater core heat with cooling system (auxiliary pump) at idle (1) & a Behr radiator and Behr/Heat expansion tank autopsy (1) (2) & request for another Behr surge tank autopsy (1) & why new made-in-China Behr/Hella expansion tanks are DOA (1) & E39 Fan shroud removal DIY (Besian) (M54) & some of the better cooling system DIYs (cn90 1997-1998 M54TU) (cn90 V8) (aioros '99-03 M54) (Ågent99 '01 530i) (pelican 3-series) (bluebee M54B25) & tricks to replace the fan clutch nut (1) & lower-hose thermoswitch o-ring (1) & to non-destructively remove the heater hoses (1) or radiator nipple (1) or expansion tank nipple (1) (2) or Oetiker clamp (1) or misplaced thermostat wiring loom (1) or broken bleeder screw (1) & modifying the cooling system pressure cap (1), or using propanol-based zero-pressure fluids like NPG+ (1) (2) (3) (4) (5) or all-aluminum cooling system parts by Zionsville (1) (2) (3) aluminum radiators & what happens if you drive one mile too far with an overheated BMW cooling system (1).

Hm. Just did my CCV and VANOS (22 hrs of cussing) and my brass bleeder screw O-ring is similar in shape to my VANOS O-ring-that is, it's not round. Replaced the plastic screws in October, at 168,000km. Now at 173300. YMMV.

Originally Posted by bluebee

Old Faithful strikes again.

Originally Posted by oembimmerparts

Glad you are happy with them Mack

Thank you for your order.
Max

Appreciate you guys. Best price in town and lightening fast shipping!

Originally Posted by AnotherGeezer

Just ordered a pair for my ride too. Going to be heading up Mt. Washington this weekend with few fellow Bimmer pilots and bleeder screw failure is not an option.

+1!!

How did yours "fail completely"? It looks in tact in the picture.

Doh, just had a bleed screw go out on me yesterday. It went to pieces with little or no force. Temporarily replaced with a rear hub/bearing bolt shortened and wrapped in PTFE tape.

Originally Posted by moots

niceeeeeeee................but on hindsight...now that the bleeder screw is strong-er....wouldn't there be a possibiity of the PLASTIC threads on the radiator side stripping?then we'd have to make brass radiators....brass thermostat housing....brass etc etc........and finally a car made of brass.....oh those german engineers.......!

Amen. It has left me wondering how much of the other plastic junk can be replaced cheaply.

Originally Posted by BigCo540i

How did yours "fail completely"? It looks in tact in the picture.

That was the replacement my indy hooked me up with to get me back on the road. The original one (from a 6 month old expansion tank no less) broke right at the top and left the threading in the expansion tank. I couldn't get it out but my indy did fairly quickly.

Gotcha, kinda like they way my expansion nipple broke off for no reason. There is definitely something up with the type of plastic that they used for these things.

The brass should be better as long as you take your time installing it and don't ever touch it again....I'm sure the plastic threads will strip in a heartbeat.

I have an aluminum thermostat housing. It was super cheap and has a brass screw in it.

Originally Posted by 96 GGM 528I

I have an aluminum thermostat housing. It was super cheap and has a brass screw in it.

Where did you get it? The Zionsville expansion tanks are pretty pricey.

I got the thermostat housing from ECStuning. I think it was like 20 dollars. Figured it is better then that junky plastic thing. It came with a seal in it also. For the expansion tank I still have the crappy plastic one.

Oh ok I read that wrong. Yeah oddly for the 528 there are some great aluminum thermo housing options out there. Unfortunately for the M54 there are very few. I spent several days researching lately and came up empty handed so had to swap out for another stock plastic housing. I expect it to fail at another 80k like clockwork.

Originally Posted by Mack

Oh ok I read that wrong. Yeah oddly for the 528 there are some great aluminum thermo housing options out there. Unfortunately for the M54 there are very few. I spent several days researching lately and came up empty handed so had to swap out for another stock plastic housing. I expect it to fail at another 80k like clockwork.

Maybe the NPG+ allevietes this problem? I had already 3 of those electronically T-stats fail on me. I use the car as aDD, so I have to drive through lots of stop and go traffic. Numerous times the temp went up to 98°C. Since I had the NPG+ I saw sporadically a max temp of 96°C. Every time, the "electronic" part failed. Maybe with a tad lower temps, the t-stat might last longer.
I also tried different approaches (read Zionsville T-stats), but beside the unusual high price, they were not available. This made the conversion to NPG+ even more palatable. Now I wait and see how long these T-stats will last. And being a brass screw thread, yes I have both changed as well. And they fail because they are made out of lousy plastic. Maybe the upper radiator hose has a better plastic, because that was the place where one of my plastic screws desintegrated as well.

I just got the npg plus and am pretty excited to get it in there. will post on your zero pressure thread with results and initial impressions once it is in.

Originally Posted by 96 GGM 528I

I just got the npg plus and am pretty excited to get it in there. will post on your zero pressure thread with results and initial impressions once it is in.

Make sure you bleed ALL coolant - the bottom of the engine block holds almost 1/2 gallon of coolant. You need to take off the engine block plug. Also, some coolant will stay in the heater core - you need to take off one hose that goes there (on my car there were 3 hoses - at the firewall) and blow some compressed air - it will disloge it. Flush a couple times with water.

Good luck

I have brass screw envy

Originally Posted by Shires

Temporarily replaced with a rear hub/bearing bolt shortened and wrapped in PTFE tape

If this "rear hub/bearing bolt" is a good fit, it would be useful, in the future, to point others to it - for the emergency run to the stealer to replace a broken bolt.

For example, when mine broke in half, I hitched a ride with a friend instead of driving my bimmer to the stealer for the replacement. Had I known of a temporary bolt that would fit, I might have saved the now-owed favor.

But ... I'm confused by your suggestion as I don't know 'which' bolt you're talking about.

Would someone kindly post a picture or diagram pointing to this reputed near-fit for the bleeder screw for temporary fixes?

Originally Posted by bluebee

If this "rear hub/bearing bolt" is a good fit, it would be useful, in the future, to point others to it - for the emergency run to the stealer to replace a broken bolt.

For example, when mine broke in half, I hitched a ride with a friend instead of driving my bimmer to the stealer for the replacement. Had I know of a temporary bolt that would fit, I might have saved the favor.

But ... I'm confused by your suggestion as I don't know 'which' bolt you're talking about.

Would someone kindly post a picture or diagram pointing to this reputed near-fit for the bleeder screw for temporary fixes?

I used part number 3 on the below diagram. However, it's definitely not something that you want to take off your car. I had some lying around because I keep old fixings for hack jobs like this. realoem.com says this is a M10X1X31-10.9.

It works for the bleed screw at the thermostat but not on the radiator neck as the bolt head does not clear the fan shroud.