Hydrolock Anyone? NEED HELP!!! please.

[LadyFF26]

My mechanic has told me that my '02 X5 experienced what is known as a HYDROLOCK. After looking further into this issue, it looks like pre-'04 BMW x5's experience this regularly. Has this ever happened to anyone? Here is the explanation taken from a savy guy named Critter7r from bimmerforums.com...

The ambient temperature isn't the cause of the problem. The cause of the problem is not driving the vehicle for more than 30 minutes at a time.

Quick lesson: the CCV works by taking air inside the engine and separating out the oil vapor that is in that air by swirling it around (kinda like a centrifuge) inside the oil separator (or crank vent valve, or cyclone valve) and the oil sticks to the outside of the cyclone valve and drips back down into the [COLOR=blue ! important][COLOR=blue ! important]oil [COLOR=blue ! important]pan[/COLOR][/COLOR][/COLOR], and the air gets sucked back up into the intake manifold.

What happens when you jump in your car and drive 4 miles to work is this: the condensation (that is inherent in raising the temperature of the oil while the metal surfaces of the engine remain relatively cool) coagulates in the oil passages. One of those passages is the tube from the cyclone separator that goes back down to the oil pan. Over time, this repeated short trip driving causes the coagulated oil and condensation to build up inside that passage that goes from the cyclone sepatator to the oil pan. Here's the important part: Since the cyclone separator drain tube is not under pressure, it's more prone to blockage by coagulated oil and water (also known as that milky whit sludge we've all seen). Here's the REALLY important part: When enough condensation gathers in the cyclone separator after the engine is shut off and the temp is below freezing - VOILA! Hydrolock cause by oil ingestion. Because instead of the oil drining back to the oil pan (the tube is frozen shut, remember?) it gets carried back into the [COLOR=blue ! important][COLOR=blue ! important]intake [COLOR=blue ! important]manifold[/COLOR][/COLOR][/COLOR].

this explanation makes sense, but I need more details as to WHY this could happen in cold weather, especially if it's a major defect in the design....my aftermarket warranty company tells me that they will not pay for problems caused by "inclement weather"....I do not think that it's 100% because of cold weather, but I could use anyone's opinion...expert or not so I can gather ammunition to resolve an invoice that will total over $7,000 with the warranty company.

[vinuneuro]

The oil separator problem is very common with BMW engines, and unfortunately if not caught soon enough, hydrolock is the end result. Water got into your cylinders (which the pistons cannot compress). If your engine is hydrolocked, you basically need a new shortblock.

Which aftermarket warranty company? It is not caused by inclement weather. The problem is caused by what could be considered a defective design of the oil separator. It happend because you made short trips in the cold, and the condensation could not be burnt off. In the end though, it is something that should be covered by your warranty. We had an oil separator problem last winter with our X and had it covered by Warranty Direct.

[LadyFF26]

Thanks for the reply---I have VSC Premier. There is verbage in the warranty docs that state "not covered by incliment weather"...what words did you use to explain the problem w/o getting into the weather situation? It sounds like I will be researching the oil seperator issues and go from there??? I'd like to be able to completely understand what it is I need to tell these suits to make them ante up to this problem....all suggestions on what to tell them are highly valued.

[JCL]

I got your request, but I am not sure how much new information I can add to what has already been posted. To assist you in your research, I have provided a short course in the issue. In answer to your question, BMWs do not regularly experience hyraulic lock. (As an aside, call it hydraulic lock instead of hydrolock, which is slang. You mention that you are dealing with suits, so it will help. Hydrolock is like calling a transmission a tranny, or a differential a diffy)

The oil separator issue has been around for some years on BMW engines. BMW has made several design modifications to reduce the likelihood of problems, but IMO it can still happen even with the modifications. The mods consist of insulated or heated drain lines.

Short trips are bad for engines, and even more so in very cold weather. The moisture (condensation) never gets boiled off from the engine oil, and eventually makes a milky-white paste that can been seen inside the oil filler cap. The real solution is to ensure that the engine gets hot enough, if not every trip, then at regular intervals. That burns off the water, and the oil is fine. Oil doesn't freeze, only the water does.

The BMW oil separator can get clogged by this paste if it builds up, then the drain line freezes up, and the engine crankcase is then essentially pressurized instead of vented. The usual result is that oil is pushed out of gaskets and other points, causing smoking when the oil hits the exhaust manifold. The usual failure point is the valve cover gasket.

In some cases, oil or condensation can drip into the intake manifold. Any liquid that enters the cylinders can potentially cause a hydraulic lock. It takes a fair amount of liquid to do that, and it isn't by any means automatic that a hydraulic lock will happen even if liquid gets in the cylinders. It can cause a bent connecting rod. Again, that isn't automatic. A hydraulically locked engine can sometimes be repaired by removing the spark plugs, evacuating the liquid, inspecting the cylinders with a boroscope, and if all looks OK, putting it back together. If it has been determined that the connecting rods are bent, then you are looking at a major engine repair. The price you mention is conceivable, but we have no way of knowing what they are planning to do for that price.

BMW may assume some responsibility, but they are likely not required to if you are out of warranty. You could ask your dealer if they are assuming any responsibility given the history of failures. It would likely be a cost-sharing arrangement for the repair, at best. They will not pay for a repair done at other than the dealership. Any aftermarket warranty is not so much a warranty as an insurance policy. As with all insurance policies, the insurer will work to maximize sales revenue while minimizing payouts. If they have an exclusion covering weather, it seems to me that they will try to play that card. I do think that that clause should be applied to floods (as an example) rather than cold weather when you expect your vehicle to operate. At the ambient temperatures you are likely operating in, the vehicle battery starts the engine, the antifreeze is protecting the coolant from freezing, and other vehicle systems function. Suggesting that the cold, by itself, caused the problem is illogical IMO.

In summary, the oil separator problem is well known, but it by no means happens to all BMW vehicles. I had lots of trips in very cold weather in my '03 3.0, and never had a problem. Short trips makes the problem more likely. A problem with the oil separator usually results in the engine forcing oil out of the engine. It can result in the oil or condensation being forced into the intake manifold. That can potentially cause a hydraulic lock. That can result in major engine repairs. It is just that all the stars have to line up (the wrong way, in this case) for the oil separator to cause a hydraulic lock. Blaming it solely on the weather doesn't seem reasonable, but as I said above, that is how insurance companies work.

Good luck, and let us know how it turns out.

Jeff

[swissfrank]

Originally Posted by LadyFF26

...but I could use anyone's opinion...expert or not so I can gather ammunition to resolve an invoice that will total over $7,000 with the warranty company.

Lyn,

Well Jeff definitely had another very informative post, between that and the others that have contributed, I think they pretty much covered all I had to say.

Except, has the work already been done... Or is that a tentative estimate, either way, what was/or is going to be the extent of the repairs? It won't give you much ammo to fight the warranty company, but to me, I seems incredibly unlikely that you'd actually end up hydro locking the engine to the point of engine damage from condensation. You'd need a pretty substantial amount of fluid to do so, my friend ended up sucking up a lot of water after driving through a big puddle (with a CIA and on a completely different car) and ended up only bending one of the connecting rods, a big deal none the less but something to put it into perspective.

What exactly is wrong with you car? Does it run at all? Blue smoke, lots of steam? Pissing fluids out from the engine? If it's something small that isn't effecting the drivability of your car, I don't see why your mechanic couldn't use compressed air to blow out the oil passage, or you taking your car on good drive to clear up the condensation, unless of course your engine is definitely hooped... My two cents, hope that helps...

[LadyFF26]

Gentlemen,
Thank you so much for taking the time to respond---I feel like I have just been indoctrinated into hydraulic lock 101. So very informative---thanks again. I definitely will feel more educated when I talk to my mechanic tomorrow, and sooner than later my waranty co. and BMWNA, as necessary.

I live 10.08 miles away from work, and do that drive every other day, for only 2 days a week (firefighter schedule, 1 day on - 24 hrs., one day off - 24 hrs, 1 day on, 5 days off), and then I travel many miles more than that during the course of the week. To put it mildly, I bought the car with 30k miles on it 3 yrs. ago, and have put 60k on it to date. So, I am wondering if the condensation theory really applies to me, put I am going with it because I think all of the stars have aligned for before in a bad way....
SCENARIO the day it happened:
I worked the overnight, the temp. outside was about 15 degrees, the car sat for 24 hours in thie cold (usually is housed in a garage), I started it up, seemed like a rougher start than normal, and went back into the firehouse for about 1/2 hour. When I came back out, the engine was off (siezed at this point, I'm assuming), I tried to start it again, no luck, tried to jump it, no luck....had it towed to my mechanic, and Presto, I have "hydrolocked my engine". My mechanic knows a guy that worked at a local BMW dealer for years, so my car is actually with him, in his home garage getting repaired. According to this new mechanic, he is very familiar with this problem, as he has seen it before, and thinks he can fix it without further problem...the issue is the REASON for the cause of the hydraulic lock, which I think you guys have been so generous in helping me understand. So that's it in a nutshell...
Oh yes, I see that Frank asked about the extent of the repair...the mechanic mentioned that the plugs were crushed...I know that may make sense to you, but I assume that the rods (don't know how many) are completely shot, and the plugs took on a force that was obviously huge...the repair bill is not set in stone, but is in the upwards of 7k+....but the warranty cost me 4k...all of which I will loose if I'm not careful on how I present this case to the appropriate "suits". That's a total of OVER $11,000 for a problem that I couldn't anticipate OR PREVENT due to a bad seal design....hmmmm. I'm frustrated, and that's putting it mildly.

So, THANKS GUYS for ALL of your time to help me!!! I will respond back as soon as I get somewhere, whether good or bad, to give an update as to haw it all came out.

Lyn

[JCL]

Lyn:

It appears your mechanic is doing things right.

One comment would be that while you may have driven it enough to warm it up given the miles on it, idling an engine in the cold is not good for it. The engine doesn't warm up as it has no load on it. Not saying that you shouldn't be able to idle an engine in the cold, but it would be far better for the engine to drive it after starting it. That won't help you at this point, but it may help others.

Good luck

Jeff

[primetime]

Anyone have any idea, how much an oil seperator replacement costs?

[lo_jack]

Shops charge you like $1300 for a seperator job. Or you could do it yourself for $350 in dealer parts.

OP - I am assuming pulling the plugs was pursuant to checking the valves for damage?

If there was no valve damage, I see no reason why that engine should not be able to run again. You could have washed out the cylinders but it need not have occured.

I used to do a fair bit of deep fording (in my 79 Dodge) and whenever we thought we had or actually did get water into the cylinders, we shut it down, pulled the plugs and cranked it over. Do you know what the extent of the damages is at this point? I am curious to know.

The starter turns the flywheel, which turns the crank. That pushes the water out of the plug holes. That pretty much only works with V engines I suppose, but the point is water in the combustion chamber does not mean death sentence.

The CCV system on these cars is interesting. It has its upsides, but for you cold climate people it seems to be ill adapted.

[toddj]

Same issues for me... Hydro-locked X5...
Caused by the oil separator system freezing. I'm going to try and go after the dealership some. I have sent them emails with no response yet. I don't imagine I will get anywhere with them...
My mechanic is doing the plugs, plug connectors, dip stick guide tube (is this really nessasary?), improved oil separator kit, hose, gasket, etc...
The compression test seemed to be ok... so I have my fingers crossed...
But in truth... we won't know until all this work and money is spent as to the extent of the damage...
Hope it works out for all of you as well, I will update as I know more...

What are your thoughts on block heaters, oil heaters???