Documenting my experience with ARX(stuck rings?)

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Black smoke is excess fuel richness or possibly carbon.
But you have all sorts of problems.
That low compression is scary, but if it is even, maybe the cam timing is off.
 
Originally Posted By: mrclam
Latest data:
1) The bang last night and the subsequent ticking was caused by a failed spark plug. The electrode in the center blew out of its mounting point in the center and was basically spinning freely separate of the four prongs.


Let me take a guess; you are NOT using NGK spark plugs? How about Bosch? Or E3 or Spitfire??

- Vikas
 
Originally Posted By: Vikas
Originally Posted By: mrclam
Latest data:
1) The bang last night and the subsequent ticking was caused by a failed spark plug. The electrode in the center blew out of its mounting point in the center and was basically spinning freely separate of the four prongs.


Let me take a guess; you are NOT using NGK spark plugs? How about Bosch? Or E3 or Spitfire??

- Vikas

Bosch
 
Originally Posted By: oilboy123
Well the compression sure came up fast, that's for sure.


Could have been a bad meter the first time, we really won't ever know
frown.gif
 
Originally Posted By: mrclam
Originally Posted By: oilboy123
Well the compression sure came up fast, that's for sure.


Could have been a bad meter the first time, we really won't ever know
frown.gif



Years ago I remember a POS compression gauge that had a rubber like cork with a hole in it which was shoved into the cylinder. Then you'd crank the engine and read the meter, it was a 2 man job. The readings were not accurate at all. A good compression gauge threads into the cylinder. It could have been a bad meter as you said.
 
OP Did you do the compression test with all spark plugs removed and WOT while cranking? One of the issues with Alusil M blocks is higher rpm when not up to operating temp,they will pass oil past the rings like mad (this is built into the design because of the non use of sleeves and relief hole in the pistons in the ring area).

Is your engine reaching operating temps?Thermostat issues can be the root cause oil burning in these engines.Repairing the cause will usually immediately bring the issue into normal consumption parameters.

Edit Are are dealing with a U.S. spec car and not a Euro spec that may have a late Nikasil block?
 
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Originally Posted By: Trav
OP Did you do the compression test with all spark plugs removed and WOT while cranking? One of the issues with Alusil M blocks is higher rpm when not up to operating temp,they will pass oil past the rings like mad (this is built into the design because of the non use of sleeves and relief hole in the pistons in the ring area).

Is your engine reaching operating temps?Thermostat issues can be the root cause oil burning in these engines.Repairing the cause will usually immediately bring the issue into normal consumption parameters.

Edit Are are dealing with a U.S. spec car and not a Euro spec that may have a late Nikasil block?


Hi Trav,
I did crank the motor at wot with all of the plugs removed. However, I do admit the car was not at operating temperature(i had driven it 2 miles prior to the test). I don't know if the engine is hitting operating temperature(gauges show coolant temp, but not oil temp). Dealing with a US car. I will be getting a leakdown test tomorrow.
 
Check the crankcase ventilation pressure regulating valve,common failure and cost around $90.Some of the failures related to this valve are..

Failure to separate the oil from the gases, instead sending motor oil into the intake. This will cause excessive oil consumption, smoky exhaust, fouled spark plugs, poor running, oily intake, etc.
Air leak - allowing excess, un-metered air into the intake. This can cause a lean condition, misfires due to lean condition,etc.

These things were known for thermostat issues in these years and IIRC was updated,it may be reasonable to swap it out for a upgraded OEM part if the engine still has the original.

1 ltr per 1-1500km is not uncommon in these engines,many people report lower consumption with BMW 10w-60 AKA Castrol RS and later Edge(Euro not U.S. Edge)

Proper ring seal cannot be expected on these engines without being close to operating temperature.A leak down test will probably show results what may seem unacceptable,again the rings need to be sealed so the engine should be close to operating temp.Operating temp can only be achieved with a properly operating thermostat.
 
I have no idea if your car came with OEM Bosch spark plugs. If it did not, you should seriously consider switching to NGK.

The "four prong" Bosch (and E3 and Spitfire) are gimmick spark plugs; stick with quality spark plugs.

- Vikas
 
Originally Posted By: Trav
Check the crankcase ventilation pressure regulating valve,common failure and cost around $90.Some of the failures related to this valve are..

Failure to separate the oil from the gases, instead sending motor oil into the intake. This will cause excessive oil consumption, smoky exhaust, fouled spark plugs, poor running, oily intake, etc.
Air leak - allowing excess, un-metered air into the intake. This can cause a lean condition, misfires due to lean condition,etc.

These things were known for thermostat issues in these years and IIRC was updated,it may be reasonable to swap it out for a upgraded OEM part if the engine still has the original.

1 ltr per 1-1500km is not uncommon in these engines,many people report lower consumption with BMW 10w-60 AKA Castrol RS and later Edge(Euro not U.S. Edge)

Proper ring seal cannot be expected on these engines without being close to operating temperature.A leak down test will probably show results what may seem unacceptable,again the rings need to be sealed so the engine should be close to operating temp.Operating temp can only be achieved with a properly operating thermostat.


Is that valve the PCV valve(oil separator)? Symptoms sound like it would be, changed that out about 1k miles ago. Do you have any more information on the thermostats? I haven't heard anything about bad thermostats on these cars, but its definitely something I'll look into.
 
Originally Posted By: Vikas
I have no idea if your car came with OEM Bosch spark plugs. If it did not, you should seriously consider switching to NGK.

The "four prong" Bosch (and E3 and Spitfire) are gimmick spark plugs; stick with quality spark plugs.

- Vikas

Interesting, I ran NGKs on my last M3, but my mechanic put in the 4 prong Boschs and didn't bother questioning it. What kind of problems or issues would you see from a 4-prong vs a better one?
 
Number 2 in this diagram.I will try to find more info on the thermostat,i remember doing a 90,s M car and was told by the dealer they had changed the part.
Even if you don't change it make sure it is opening at the specified temp.I will look for old documentation and part#
I don't recall any issues with Bosch plugs in BMW engines,they are OEM and designed for that engine i have also seen Beru ulta X being used in M engines with no complaint.

bmww.jpg
 
Can't see the picture right now(must be blocked by the work firewall), but will check it out when I get home. Got the leakdown done today, numbers from 5-12 for 5 cylinders, and 22-30 on the last one(depending on the threaded connectiong used to plug into the spark plug hole). My mechanic diagnosed a piston ring as the culprit, and told me that a stuck ring is very unlikely in this case. Incidentally, the weak cylinder is the same one that destroyed the plug.
 
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He would know a lot more then we would he is on the ground so to speak.Broken rings in the alusil and nikasil blocks many times tear the wall up and require a new block,genie in a bottle isn't going to fix it if they are in fact broken.Good luck with this problem i hope you find a solution that doesn't break the bank to hard.
 
Originally Posted By: Trav
He would know a lot more then we would he is on the ground so to speak.Broken rings in the alusil and nikasil blocks many times tear the wall up and require a new block,genie in a bottle isn't going to fix it if they are in fact broken.Good luck with this problem i hope you find a solution that doesn't break the bank to hard.


His recommendation = new motor :)

rebuilding the block would cost easily in the 4-5k range, whereas I can pick up a used one for 2-3k or so, and drop it in for 1.5k, and sell off the parts on the used one. I'll drive this one while it still holds up, and start looking for its replacement.

I'll keep updating what happens with the auto-rx in the meanwhile and see if there are any appreciable gains in the near future.
 
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Originally Posted By: sprintman
How many bottles of RX do you have in the sump?


1.5
 
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