318ti overheat and Radiator leak

[zoner]

Originally Posted by AyseOne

want to change the water pump but cant get it out of the block, seized, seems to work though.

It's not easy to remove if it's been in there awhile. Not the recommended procedure, but I used the claw end of a claw hammer and a fulcrum to get it out- didn't care if I trashed the WP on the way out (which I didn't, BTW) because a new one was going in. Just be careful not to destroy anything else in the process.

If someone has a better, recommended procedure on WP removal, please share.

[AyseOne]

thanks zoner,

that's exactly what i tried to do after i broke the casted threaded holes on the water pump which your supposed to use to press it out with 2 bolts. just shattered, totally brittle.

i tried to leverage out the water pump with a 4 foot pipe actually using a claw hammer as the fulcrum against the block. soaked it with penetrating oil too. couldn't get it to budge.

thinking about making some kind of custom puller. unfortunately the only place to pull from is there you mount the pulley. hope its strong enough.

any suggestions would be appreciated.

[cooljess76]

DO NOT, I repeat DO NOT, pry on the water pump or anything attached to the aluminum timing cover. If you crack that timing cover or mar the edges where the water pump housing mates up to it, you're in a world of sh!t. The timing cover isn't something you want to replace. Unless you just feel like raising the engine, removing the oil pan, removing the valve cover, removing the timing sprockets, removing the crank pulley(this requires a 4ft breaker bar to break loose the M16 stretch bolt which is torqued to over 250ft lbs and will need to be replaced with a new one and torqued with a monster of a torque wrench), remove about a dozen bolts holding the timing cover on, then you get to replace the timing cover gasket, valve cover gasket, oil pan gasket, front crank seal, reinstall the timing sprockets, time the cams(which requires BMW special tools), loctite and torqueing everything as you go and hope you didn't miss a step and nothing leaks, do an oil change, add coolant and bleed the system and reinstall everything else you had to remove to get access to the timing cover ie; radiator, alternator, power steering pump & reservior, fan, airbox and anything else I left out.

The water pump gets stuck in the block because the o-ring is really thick and compresses to give a good tight seal. You need to lube it with silicon grease prior to installation and you could imagine that after 10 years of heat/cooling cycles the grease dries out. You end up with a water pump siezed into the block. No worries though. The extraction bolt method usually never works successfully and results in a shattered water pump housing. It's better than a shattered timing cover though!

The best way I've found to remove a stuck water pump is to remove the fan(gives you a little more room to work), remove the water pump pulley and all of the mounting bolts, Then take a big ass pair of channel lock pliers and grip the entire water pump housing. Gently rotate it side to side while slowly working it forward out of the engine block. Once you think it's ready to come out, take extra care not to let it slip and slam into the radiator. Replace it with a new one and a fresh o-ring. Lube the heck out of the new o-ring with silicon grease prior to installation.

[zoner]

Like I said- I knew it wasn't the recommended procedure, but I took my time and did my best not to put too much pressure on the timing cover because I was aware of the potentially disastrous consequences. Once I felt that I had broken the seal slightly, I took several minutes working it out the rest of the way.

[AyseOne]

Good advice cooljess.
I'll be sure to treat that timing cover with care.
The suggestion to use rotational force rather than prying is much appreciated.
I will get after it with some big ass channel locks or maybe a chain vice grip.
I'll let you know how it goes.

[cooljess76]

I've shattered more than one waterpump housing trying to remove them with the extraction bolt method. In hindsight, I think that method would yeild a higher success rate if the manuals incorporated a step which involved gripping the pump housing with some rubber-lined pliers and rotate it side to side a couple of times to break it loose prior to threading down the extraction bolts.

[zoner]

Originally Posted by cooljess76

I've shattered more than one waterpump housing trying to remove them with the extraction bolt method. In hindsight, I think that method would yeild a higher success rate if the manuals incorporated a step which involved gripping the pump housing with some rubber-lined pliers and rotate it side to side a couple of times to break it loose prior to threading down the extraction bolts.

Agreed. The extraction bolt method did absolutely zero for me when I was trying to remove mine. I think I ended up breaking one of the ears off in the process.

Pelican's DIY makes it sound a little easier than it actually is:

http://www.pelicanparts.com/bmw/tech...water-pump.htm

[AyseOne]

So here is the update on my cooling system issues.
I replaced the thermostat and the radiator (which was leaking below the expansion tank).
I still want to replace the water pump as i can hear the bearings clicking away, but have shelved this for a moment after the difficulty removing it as i try to diagnose other issues. It seems to be circulating coolant adequately.
With the new parts I have done my best to bleed the system of air as described in many threads on this site. Here is the problem:
I can run the engine at idle with the bleeder screw and the radiator cap off without issue. The coolant circulates, the engine does not overheat (needle steady top center), and the heater is blowing warm/hot. Not super hot, but on its best day this car never has.
Now, when i replace the bleeder cap the expansion tank level starts to quickly rise and will overflow if i do not remove the bleeder screw or quickly cap the radiator. If i remove the screw it geysers out air and water from the bleed hole and the expansion tank level goes back down. If I cap the radiator pressure builds up and it vents out the cap. I am worried that this will crack the new radiator so i don't push it too far.
Airlock seems to be evident despite my repeating of the procedure for bleeding the system. My growing concern is that the air is actually combustion gas getting in the system from a blown head gasket in the overheating event. Hence why I cant bleed it out. Big bummer if the case.
So I performed the block test for combustion gas in the system. Fluid stayed blue, good sign. However, I was forced to run the test with the bleed screw out or I would have overflowed the expansion tank making the test impossible. Maybe this compromised the test by allowing the gas to escape through the bleed hole and not the tank where the tester was.
A compression test will be next to again try to assess the head gasket, block, and head for leaks into the cooling system. I also plan to run some radiator cleaner through the system to try and break up any debris that might be causing airlock, such as in the heater core.
Any advice is appreciated. Hope i can save the ti.
Thanks!

[cooljess76]

try doing it while the engine is still cold. When you add coolant to the expansion tank, make sure the bleed screw is out and fill the expansion tank all the way to the top of the filler neck to just before coolant starts to overflow out of the tank. I'm assuming you're getting a geyser because the coolant temp is already at or near boiling. The whole bleeding process shouldn't take more than a minute.

[AyseOne]

cooljess76, thanks for pointing out what should have been more obvious to me. I was running pure water because I was still working on the whole cooling system and wanted to flush it out a couple times anyway. Clearly water has a lower boiling point that 50/50, lowered even further by not being pressurized. Hence the air was from boiling water, not combustion gas. Now I have it all back together with 50/50 coolant and water wetter too. Now the cooling system is running fine so I gave up on the water pump replacement plans. Just seemed like too much of a risk for preventative maintenance. It I really destroyed it or damaged the timing case like you said, id be a lot deeper in it.

Here's my new problem, and blame rests fully on me for this one. I still wanted to feel confident about the health of the engine overall after overheating so I decided to run a compression test. I followed the directions on the tester and watched a couple videos on line, felt comfortable with the procedure. I got consistent numbers from all cylinders so I felt good. The spark plugs also looked good and they all went back to the same cylinders. I went to the bentley manual afterward to see if it listed the normal specs for compression. It did, and I came out well over. It also listed another important detail, that the DME relay and fuel pump relay should be removed before running this test. DOH! I didn't see that anywhere else. Should have checked the book first! Now I have a cylinder 3 misfire (P0303). The engine is running rough and lacks power, and is jumping around on its mounts so that's definitely the case. I also got codes for the crankshaft position sensor (P0340), and an evap system large leak (P0455). The camshaft code was coming and going for a while before this. The Bentley book says it is possible to damage the engine control module (DME) by not removing the relay.

So what do you think? Did I damage the DME, the injectors, or something else? Getting ready to give myself the old dope slap for this one. Thanks!

[AyseOne]

Just a follow up for anyone interested.
The misfire turned out to be from a bad ignition coil. Somehow the compression test was to blame. I got one used from Robert x on bimmerforums and if fired up great. Glad it wasn't the computer, bentley book had me scared.
After flushing the cooling system and burping it properly a couple times the heat is even blowing hot for once.
Thanks for the help.

[Kaliimc]

I was hoping to hear a better solution to the "bottom of the expansion tank" leak since that's what mine is doing; albeit slowly.

No overheating, new Behr radiator, pretty new thermostat, hot hoses up and down excellent heat although very rarely used in Hawaii. . .

Anyone have other bits of knowledge and experience in this area?

[Kaliimc]

Originally Posted by Kaliimc

I was hoping to hear a better solution to the "bottom of the expansion tank" leak since that's what mine is doing; albeit slowly.

No overheating, new Behr radiator, pretty new thermostat, hot hoses up and down excellent heat although very rarely used in Hawaii. . .

Anyone have other bits of knowledge and experience in this area?

Checking in on this again; anyone experience the issue where coolant leaks from the bottom of the expansion tank where it joins the plastic parts of the radiator? This is still a fairly new radiator.

[rennerb]

Mine was a cracked recptacle where the resevoir bottle seats near the hose connection

[DDubbs]

Try replacing the 0-ring and needle gaskets. I read some forum entries where that solved the oveflow tank leak. Here's the realoem exploded view of the part.

Start small with the gaskets and work up to the bigger stuff. They're rubber too and wear out over time.