BMW COOLING SYSTEMS ANGER ME!!!

[DueceMcCracken]

I need some troubleshooting tips. here's whats up

New Rad
New water pump
New T stat
New plastic block coolant connectors
A few new rad hoses

Apparently the previous owner's mechanic did not retrieve all of the broken propeller pieces of the old water pump.

My car will drive fine some times then other times do the following

No hot air through heater.
Top rad hose hot bottom cold
Coolant bubbles out rad cap at normal operating temp as well.

I am thinking these three things are what I should do.

Undo coolant hoses and tstat in order to backflush the water jacket in a attempt to remove plastic pieces.

Check tstat for proper function

replace rad cap.

Should I remove the water pump for the flushing? Or do you think I can knock the crap out with just the open tstat mounting area.

I have performed a coolant flush already but it was just draining out the block drain and rad drain.

I figure if I disconnect the main rad hoses I can get the piece or whatever out.

HELP!!!

[cooljess76]

Your cooling system has whats called an "Air-Lock". You need to bleed the air out of your cooling system. This involves parking the car on a hill or incline with the nose elevated. On a cold engine, start the car and turn the heater on full blast. Remove the radiator cap and bleed screw next to it. Slowly add coolant/water until it starts flowing out of the bleed hole. Allow all of the air bubbles to escape from the bleed hole, gently massaging the radiator hoses while pouring coolant into the expansion tank. Once a steady stream of coolant free of air bubbles starts to flow from the bleed hole, cap it off and replace the radiator cap. Drive the car around the block a few times. Repeat process as needed. It might take a couple tries to get all of the air out, but you will notice an increase in heat from your heater if the process is performed correctly and your system is functioning properly. Of course wait until the engine has fully cooled before you attempt to remove the radiator cap and bleed screw.

BE SURE TO HOSE YOUR DRIVEWAY DOWN! so no dogs or cats can consume the coolant and become poisoned.

[DueceMcCracken]

I have bled the shiznit outta my cooling system. I keep bleeding it. The car is fine most of the time. Then all of a sudden it's overheating. Even when doing 50 mph in 5th it will just start overheating once and awhile. It's crazy. Would an air bubble cause this? I understand what would happen. Would it be that inconssistent though?

It's not a fan issue. I have my fan sensor jumped to have it run on high whenever the key is in run. Which works flawlessly.

Maybe my rad cap is just bad and isn't holding the pressure, it does leak coolant when the engines warm. I'm not sure if it's really bad or theres some blockage causing the overheat which causes the cap to vent. Its a tough call. Im going to replace it though to eliminate a variable.

Airlock is sounding more and more like the problem but I'm leaning towards the rad cap as the cause of the air. I take my time bleeding the system. Massaging all hoses. Till shes good. Then re-bleeding after a few heating cycles. I'm a very capable recreational mechanic.

What do you guys think of that?

Any other suggestions?

[aceyx]

Are your belts okay?

[DueceMcCracken]

Yes my belts are fine, both the serp and the A/c.

Could the rad cap affect my cooling system like this?

It's getting ridiculous.

Unless my HG is blown... Which would suck. I had some plugs out though and drained the coolant saturday with no signs of blown Hg (knocks on wood).

[aceyx]

If coolant is getting out of the cap, air is probably getting in. Under load (50mph) you're building up a fair amount of pressure in the system. I may be wrong (haven't looked at that part in a while) but you may be able to replace just the o-ring.

The reason I ask about the belt is that it could cause the issue to arise intermittently--if something on that belt is binding up it could cause the water pump to slow down. Don't know if anything on the same belt is clutched though.

[DueceMcCracken]

I also forgot to mention that the top of my rad is ice cold when I'm overheating, while the top rad hose is super hot.

I'm going to check out the T-stat. It's new though, but I thought I read something about there being a crapload of faulty t-stats floating around.

F this crap.

[pnosker]

You need to fully bleed your system. There's definitely air bubbles in it. Bring it to a mechanic and let him bleed it if you're having this much trouble. My system didn't bleed properly for several days where I had to stop at the side of the road and let my car cool down. It was a mess. Then my uncle touched the car, and it was back to normal. Well, he bled it himself... put it on an incline with the radiator cap off, all of a sudden tons of bubbles came out... filled it up and it was good to go.

[DueceMcCracken]

Well I just placed a new order for parts.

Valve cover gasket
NGK platinum 4 electrode plugs
Dual temp coolant sensor guy
New o2 sensor
3-3watt instrument cluster light bulbs
So other odds and ends

I have come to the conclusion that it may just be bad bleeding.
I'm still having a hard time with believing this is all just air bubbles.
I've bleed the system before and it was fine. This time around I had probs.
Hmmm. I will be replacing the rad cap and pull apart the colling system and totally flush it for peace of mind, then doing the most hardcore of all bleedings in all of time.

I will report my findings.

Thanks for the input.

[cooljess76]

Duece, Are you losing coolant at all?

I had a hairline crack on my radiator and for a long time I kept losing coolant. I never seen any residual coolant in the engine bay and the car drove just fine. Numerous people kept saying that I had a blown headgasket and I knew otherwise because it was losing coolant for thousands of miles. I just kept adding and it continued to run fine.

I'd imagine that if I drove it long enough without adding coolant, it would probably have overheated, but I paid close attention to it and never had problems. I also bled the system EVERY TIME I added coolant, so no air-lock problems for me.

Finally one day I decided to pressure check my radiator. I borrowed my buddy's pressure tester and pumped the cooling system up to about 20psi. I heard a hissing coming from the seam where the expansion tank meets the radiator. I then placed my finger over the area where the hiss was coming from and the tone changed. I knew I found the leak.

I guess the leak was so small, the coolant would evaporate as it dripped down the side of the hot radiator. Replaced the radiator with a Behr radiator purchased on ebay for 125 bucks along with a new water pump and thermostat. Took about 4 tries but I finally got the system bled completely and haven't needed to add coolant since.

So my question remains, are you losing coolant? If so, I'd recommend pressure testing your radiator and perhaps listen for leaks around the hoses as well while you have the system pressurized. I live in a quiet neighborhood, but if necessary you might want to do it inside of a garage. Good Luck man, hope you get everything sorted out.

[DueceMcCracken]

So my cooling system has been properly bled!!!

YEY!!

The bad news is my HG is blown.

I checked my oil and its a foamy mess.

So I'm F-ed.

I am now starting a new thread about my current "ness"

[cooljess76]

Bummer Duece, sorry to hear that, but actually you can still help my curiosity. AutoZone sells this stuff that claims to seal blown headgaskets, in fact they sell a couple different brands, but the one I seen was in a clear/opaque(like a milk jug) bottle and the liquid looked kinda blue. Since you have nothing to lose at this point, you should try it out. Heck, maybe you'll get another week out of your motor. I'm just curious because I don't see how it could possibly work, but it's worth a shot and you could post your results.

[pnosker]

Wow that sucks man. A head gasket job is a big one. Try the stuff cooljess is suggesting... it can't hurt.

[aceyx]

A very recent thread on the same subject from my other forum.

http://www.apriliaforum.com/forums/s...d.php?t=150802

Take into account *when* this should be used (essentially a last-ditch effort on a dying beast).