Overheating issue...I searched

[defigh]

Having an overheating issue with the M3. Approximately 6000 miles ago I replaced the radiator, h20 pump, thermostat etc.

Here's the story.

1. Car running normally. On the drive home from work I notice that the temp is climbing and my OBC states that coolant is low.
2. Found that the lower radiator hose was loose on the rad side and leaking a bit of coolant. Also noticed that air was entering the system at this time.
3. Refilled system with coolant and proceeded to bleed. 1st bleed was with just ignition on and engine cold. Cabin heat was on full as well. I got a fair amount of air out of the bleeder screw. Test drove the car...still overheating.
4. Second bleed was with the car running, revving and adding coolant. Again a good amount of air came out. I stopped bleeding when just coolant, no air was coming out of the screw. While idiling, car did not overheat, but I had no heat inside the car.
5. Where I am now. I have removed the thermostat and h20 pump to check for any damage. Thermo looks good...got a new one anyway, but the water pump made me a bit suspicious. Everything moved ok, but the leading edge of the fins seemed to be damaged a bit (see pics).

At this point I am stumped. HG leak was a thought, but since I'm not getting any heat in the car, I've pretty much ruled that out (I would still get heat even if HG was toast). Is this the case of a boatload of air in the system? Is there anything else that I should check before I put everything back together and re-bleed? Thanks for the help.

[defigh]

http://i103.photobucket.com/albums/m140/defigh/Friend00358.jpg
http://i103.photobucket.com/albums/m140/defigh/Friend00357.jpg
http://i103.photobucket.com/albums/m140/defigh/Friend00355.jpg

[defigh]

Also notice wierd black deposit in pic #2. Can this pump be reused or should I buy another? Thanks

[tpb31]

are you on the original radiator? I have heard stories of people having the radiator neck crack and the pieces going everywhere.

[Gregg]

Don't mess with it. Replace your t-stat, housing, radiator, and waterpump. I did and still had to do a headgasket this weekend. Not fun.

[defigh]

New radiator. Everything seems to be fine there. I did a complete cooling system overhaul about 6k miles ago. Radiator, t-stat / housing, water pump, coolant etc

[defigh]

anyone?

[Gregg]

Replace the waterpump and see what happens.

[beatniks325]

read the understeer guide to bleeding on their waterpump guide. then do this step for step until you get hot air while the engine is at idle and also under load.

i suspect you still have air in the system based on your decription of the bleeding and then having no heat.

what is that black stuff in the second pic on the waterpump blade?
what kind of coolant are you using?

[defigh]

BMW Coolant. I'm not quite sure what that deposit is. Yeah I checked out the understeer guide a while back. I guess I'll button everythign back up and try it again. Thanks for the help.

[Gregg]

Buy a new water pump first!

[ph325is]

Your water pump is causing your problem based on the info you provided.From the looks of your pics you have a cast iron impeller. We have found that of all the aftermarket pumps this one flows the least. With the tips of the impeller being rough [like the one you have] by way of improper machining and/or a bad casting it will cause cavatation at a much lower rpm [2500 or more]. It also is a heavy impeller and will cause premature bearing failure.
I am the sales manager for EMP/Stewart Components and I am not going to push my product on you but I invite you to look at all the facts with BMW water pumps and decide for yourself. www.stewartcomponents.com (http://www.stewartcomponents.com)

Of course I am going to recommend our product, but check with Bimmer World, UUC and other support vendors about what they think of our pump. We offer a Lifetime Warranty on it for as long as you own it.

At the very least you need to buy a better pump. All your other parts radiator, thermostat if they are new then they should be ok. You can test the thermostat in a pot of water on the stove, heat it up and check the temp of the water,it will open slowly till it is at fully open, make sure the bypass plug [round plug on they end] moves away from the body. It seals off the bypass hole in the head when the thermostat opens up. Make sure there is no obstruction in the radiator, like packing peanuts...etc. Put a garden hose in one of the hose connectors and see if it runs freely and clean.

Paul Hammond
EMP/Stewart Components.

[ph325is]

I forgot to say once you have it all back together and bled properly drive it and see what you get. If it still runs hot you need to have a shop check the cylinder head and gasket. Like most cars, BMW's will not tolerate running hot and the head gasket can fail. They can warp as well so if the head has to come off be sure a machine shop checks the head for leaks and warpage.

Paul

[TheNorthWaves]

i vote that there is still air in the system

[defigh]

Thanks for all the help. I thinking new pump/etc then back together and hope for the best.

[Bassmaster]

Sounds like it needs bleeding again. Try it up on ramps.

[Badgtho is back]

make sure that your heat is on HIGH

[defigh]

Thanks again for the help. The wierd thing is that I've done all these things...tilted back, heat on high, reving 4500 rpms, etc etc.

I think I'm going to go with the Stewart pump and see how things go.

[defigh]

New Stewart H20 Pump/T-Stat/system flush/new coolant/proper bleed...and I'm happy to say that she's back and good as new. Thanks for the help.

[m3boost]

anyone?

Make sure your heater valve is open(heater on).With the car off and cool. Remove the hose clamp from the top radiator hose and pour coolant through that hose until coolant starts leaking out of the top radiator neck. Reinstall the hose and tighten the clamp..

Start the car and let it warm up..Keep an eye on the coolant level...Rev the engine to about 2500 rpms and loosen the bleed screw.. Once you start seeing coolant flow out of the bleed screw, tighten the bleed screw and check the coolant level..Add coolant if needed and place the radiator cap back on... Leave your car on for a while, while monitoring the temperature gauge.

In the morning, check your coolant level again and add if necessary..

[ZimDoc]

I would really need to be there to get a full Diag on it. I would install everything and PRESSURE TEST IT. Make sure the car still doesn't have a leak.

Also reading all of these different ways to bleeding the cooling system is so crazy and over done.

Heres mine if I didn't work as a BMW Tech and did it on the weekend.

1) Install all parts, and close up the cooling system.
2) Open radiator and bleeder screw.
3) Start filling the radiator and watch for teh air bubbles.
4) Once it seems full grab the lower Rad hose and give it some pumps.
5) Grab the upper rad hose and do the same.
6) Fill with more coolant
7) Make sure there is only coolant coming out of the bleeder screw and close up cooling system again.
8) Start the car with the heater on full and some how reduce air flow into the engine to cause it to come up to temp faster, or drink 2 beers.
9) Once the engine is warm, let it cool down. Poke Gf/wife/bf (only if your dallasfan or a girl).
10) Open just the coolant filler (NOT BLEEDER) and top off with coolant.
10.5) Close cooling system before test drive.... (Remember you had 2 beers by now, you may have forgot that.)
11) Test drive and don't go to far away from home. (Because you could get a DUI or Over Heat)
12) Come home to a cooked meal and eat.
13) Pass out because of the great day today.

SO EASY!!!!

[mobil1]

I would really need to be there to get a full Diag on it. I would install everything and PRESSURE TEST IT. Make sure the car still doesn't have a leak.

Also reading all of these different ways to bleeding the cooling system is so crazy and over done.

Heres mine if I didn't work as a BMW Tech and did it on the weekend.

1) Install all parts, and close up the cooling system.
2) Open radiator and bleeder screw.
3) Start filling the radiator and watch for teh air bubbles.
4) Once it seems full grab the lower Rad hose and give it some pumps.
5) Grab the upper rad hose and do the same.
6) Fill with more coolant
7) Make sure there is only coolant coming out of the bleeder screw and close up cooling system again.
8) Start the car with the heater on full and some how reduce air flow into the engine to cause it to come up to temp faster, or drink 2 beers.
9) Once the engine is warm, let it cool down. Poke Gf/wife/bf (only if your dallasfan or a girl).
10) Open just the coolant filler (NOT BLEEDER) and top off with coolant.
10.5) Close cooling system before test drive.... (Remember you had 2 beers by now, you may have forgot that.)
11) Test drive and don't go to far away from home. (Because you could get a DUI or Over Heat)
12) Come home to a cooked meal and eat.
13) Pass out because of the great day today.

SO EASY!!!!


Yes! And if you read a few posts back, you would know he already fixed it!!!!

Haha sorry, couldnt help myself :stickoutt

[defigh]

Yeah car is good to go now. Thanks for the info though.