Cylinder #3 has water, hydro locked up

2000 323i E46 auto. Bought new, well cared, no abused , 90k miles, replaced tranny 2 yrs ago @ 65k miles (the infamous no reverse gear) by Century West BMW dealer for $6.5K; expansion tank ruptured 4 yrs ago; replaced couple set of valve sensors; window regulators...

This morning my wife called from work said it lost power. I got there try restart the engine: starter worked but can't turn. I guessed water inside cylinder caused locked up. I removed all spark plugs, found #3 wet with water. I then cranked to pump water out. Drove it home without #3 plug+coil, limping at 5mph since ECU retarded ignition or whatever when it detected bad #3. I plan to pull the head out to check if head gasket or cracked head. Need advice on:
1) shop near Burbank 91501 for new head + valve seats, or head machining if need
2) where to buy new head if needed+ machine shop if transfer valves from old to new.
3) link info on process to head removal

Thanks in advance
Sapote

It all sounds strange. Did your wife drive your bimmer into some pond? Also hydrolocking the engine does not cause it to "lose power", it just locks, possibly causing all kinds of engine damage.

Sapote -

I'm curious if the car lost coolant, overheated, then ruptured the head gasket. That would explain the loss of power reported by your wife. The water in the cylinder could have been coolant draining into the cylinder while it was cooling down, draining from the top of the head.

As mentioned above a hydrolock situation is exactly that - a lock. I've had a motor do this and the engine stops dead in its tracks. At the minimum, bent rods and what not.

In which case you're "lucky". As a lesser of two evils, a head gasket replacement seems a lot more acceptable than bent or broken internals.

Paolo

Originally Posted by cvx5832

Sapote -

I'm curious if the car lost coolant, overheated, then ruptured the head gasket. That would explain the loss of power reported by your wife. The water in the cylinder could have been coolant draining into the cylinder while it was cooling down, draining from the top of the head.

As mentioned above a hydrolock situation is exactly that - a lock. I've had a motor do this and the engine stops dead in its tracks. At the minimum, bent rods and what not.

In which case you're "lucky". As a lesser of two evils, a head gasket replacement seems a lot more acceptable than bent or broken internals.

Paolo

I will open the head this weekend, but I agree with you, that my wife didn't check the instrument indicator often enough while driving (only 1.5 miles from home), and I think the cooland was low, overheated head, then either cracked head or blew head gasket allowing water (small quantity) into #3, enough to cause it misfire, rough engine lead to faulty knock sensing signal, lead to ECU keep retard the ignition timing, ---> lost power (~3 to 4 mph). Parked car and pressurized water continue leak into #3 ---> hyro locked. I found it locked when I first cranked, and I stop right the way, knowing instantly what's going on. I hope the lower end have no damage, not as your case on the track.

I wish it's just the gasket blow. Even if cracked head, I'm willing to spend $2500 for the naked new head (without valve train, not even the seats or guide) since this engine was in great shape (no oil burn, not even a drop added during one year 10K miles driving). I just don't know if the block, steeel cylinder liners damaged. I fear to pump in $2500 new head and find out later the engine is toast.

Any advices?

My experience here is with the M50 motor, and I also had fluid in the #3 cylinder. I had a cracked head from an overheat (exploded radiator on a mountain road), that did not show up for several months after the event. I went out one morning, the motor cranked around one time then slammed the coolant in #3 against closed valves because it was a compression stroke.

I pulled the plugs, and coolant came out of #3 when I cranked the motor around with a socket wrench.

If the valve (#3 Exhaust) is closed when the motor stops, the crack is meaningless -- well, maybe there is meaning, but not an instant problem. If the valve is open when the engine stops, then coolant can drip from the crack into the cylinder, and then create the conditions for hydrolock on the next start cycle. My car had a crack for months that I did not appreciate the impact of. I was using small amounts of coolant that was not alarming except that I was adding a half or 3/4 of the expansion tank every three or four weeks. I had no other signs of impending doom, and the amount of coolant I was adding was not in itself a problem -- except that the frequency that I was adding it should have triggered a red flag.

In any case, I found a guy in Rancho Cordova (I think) California that repairs this and puts the head back together and ships them out. I bought a head -- complete -- for a few hundred dollars, and my mechanic put it on and shipped the core back to start the cycle over again.

The crack is almost invisible if you don't know where to look. Observe the coolant galley that is next to the #3 exhaust seat. The forward one, not the aft one. The wall of the water galley will have a tiny crack that is sealed when the valve is closed -- which odds would dictate should be most of the time.

I put a head on my car, and it gave me tens of thousands of miles before I drove it into the side of a Buick that made an illegal turn into my path. You should be okay with the motor after you put a head on.

Have fun. Live long and prosper. Drive happy.

Originally Posted by cvx5832

Sapote -

I'm curious if the car lost coolant, overheated, then ruptured the head gasket. That would explain the loss of power reported by your wife. The water in the cylinder could have been coolant draining into the cylinder while it was cooling down, draining from the top of the head.

As mentioned above a hydrolock situation is exactly that - a lock. I've had a motor do this and the engine stops dead in its tracks. At the minimum, bent rods and what not.

In which case you're "lucky". As a lesser of two evils, a head gasket replacement seems a lot more acceptable than bent or broken internals.

Paolo

Did you have the issue of the head bolds pulled away from the soft AL block? And what was the preferred fixing method?

Originally Posted by Sapote

Did you have the issue of the head bolds pulled away from the soft AL block? And what was the preferred fixing method?

My accident was not on the M54, but also an aluminum block. I don't think you'll have problems.

I'm with jdstrickland on this one. Take it apart and I think you might get away with just replacing that head. Or if you're really lucky, just a head gasket.

Paolo

Originally Posted by cvx5832

My accident was not on the M54, but also an aluminum block. I don't think you'll have problems.

I'm with jdstrickland on this one. Take it apart and I think you might get away with just replacing that head. Or if you're really lucky, just a head gasket.

Paolo

looking at the amount of cooland in the chamber, I bet the gasket must has a big gap for the water flow into; a head crack alone is just too small for this. it wasn't an overnight parking; only about 1/2 hrs after my wife parked it. could a cracked head alone fill the chamber this fast? could be both cracked head and blew gasket, but i hope only the gsket.

I also look for head bolt torque sequence or pattern, spec at 40NM, 90 deg? Also, special bmw long neck E12 torx socket, or just any e12 socket will do?

Thanks,
Sapote

Originally Posted by Sapote

looking at the amount of cooland in the chamber, I bet the gasket must has a big gap for the water flow into; a head crack alone is just too small for this. it wasn't an overnight parking; only about 1/2 hrs after my wife parked it. could a cracked head alone fill the chamber this fast? could be both cracked head and blew gasket, but i hope only the gsket.

The cooling system is pressurized during operation, so it could very well fill up with just a tiny crack or break in the gasket.

Paolo