Nikasil problem on 328 and 528 M52???

[Bruno]

They have the nikasil linings, but I didn't know if they had problems with high sulfur gas like the M60 engines.

[632 Regal]

They have the nikasil linings, but I didn't know if they had problems with high sulfur gas like the M60 engines.

[DueyT]

Yup, somw M52's had the problem as well...


Only the M60 and the European M52 are affected.
The M60 is easy – it was fitted to all the E34 530i and 540i V8 cars. It was not fitted to the earlier E28 5-series or the later E39 5-series. Also the early E34 3.0 cars (pre-1991) were M30 6-cylinder cars and were not affected.

The M52 is not as easy. The E36s (3-series), E34s (5-series) and E39 (5-series) are affected. E30s, E46s, E28s are not. But not all the 6-cylinder cars are affected either. The early ones had the M50 (no VANOS) engine, and late ones had the M54 (double VANOS) motor. It is only the single VANOS M52 units that were affected (and then not even all of them). The effect of VANOS is to lower the revs at which peak torque is produced. On the M50, peak torque is produced at 4,700 rpm (2.0 and 2.5 litre). On the M52, maximum torque is produced at 4,200 rpm (2.0 litre) or 3,950 rpm (2.5 and 2.8 litre). On the M54, peak torque is produced at 3,500 rpm (2.0, 2.5 and 2.8 litre). Look at the peak torque figures in the Owner’s Handbook and your question is answered.

Once one has established that the engine is an M52, the next stage is to work out whether it has Nikasil liners or not. Steel liners were introduced into production at Week 10 in 1998, i.e. March 1998. Cars built before then will have Nikasil liners; but that is not the same thing as saying that cars sold after then will have steel liners - cars can sit around for a while, and it is the build date that is critical, not the date on which the vehicle is put into service. Contrary to certain information, the engine code change from "S6 3" to "S6 4" did not coincide with the move to steel liners and therefore not all "S6 3" cars are Nikasil. Whilst it is probably safe to assume that any car sold during 1999 or later is safe from the Nikasil issue, my advice (to be on the safe side) has to be to be very wary of any M52 and check the block material with BMW before buying it.

Also affected are the 7-series with the M52 and M60 engines, and the 8-series with the M60 engine. The Z8 with the M52 engine is not affected as all these cars received the "American" iron block (because they were built in the USA)."

[Kamil]

Yup, somw M52's had the problem as well...

Can anyone tell what is the damage that actually/physically occours, this Nikasil thing has has piqued (sp?) my mind.

Yes, I know, it's due to sulfur in the gasoline, and that's why it's also a geographical issue... does the "Nikasil problem" occour in other parts of the world, or is it more or less specifically a U.S. problem?

The engine is checked with a leak-down test. As far as I can remember (it's been some time), a leak-down test can detect a weak head-gasket, or bent valves, or bad oil rings... essentially, anywhere where air can escape from the cylinder (w/ all valves closed), will be shown.

Now, my main question.... what is the actuall damage that occours to Nikasil blocks once they are "bad"?

Thanks,
-Kamil, nikasil free :)


P.S. I've read that nikasil is used in the block of the Porsche GT.

[632 Regal]

the sulpher as it combusts in the cylinder reacts with the moisture and turns into sulphuric acid which in turn eats the Nikasil coating on the top of the cylinder bore causing the rings to leak at TDC. This in turn lowers the static compression and when real bad can cause a bad idle to a non start condition.

Neither me or Duey believes this old wives tale but there are people that swear by it.

I personally like the smell of Nikasil in the morning where all the Alusil people simply miss out on such a phenominal event.

[Sweetwater]

BMW policy checks compression first, then performs a leak down test if compression results indicate a potential problem.

Sulfur is element #16 on the periodic chart, oxygen is just above it, chloride is next to it. It is an anion with a negative charge of two. It is quite reactive and will form acidic products in combination with water. H2SO4 is hydrogen sulfide as I recall. It has been an evironmental issue in gasoline exhaust and industrial polution for decades. It is the principle culprit in acid rain and regulations have been effected to control it's production.

The nickel-aluminum-silicon liners proved to be quite susceptible to these acids in spite of the fact that they have been used long term in BMW motorcycles with no problems. Due to the manufacturing process used, there is some significant probability that many of the failed blocks did not get the amount of lining needed and that the problem lies there.

The fact remains that the majority of the nikasil blocks did not need replacement and are out on the roads. I think it's alot of noise about a smaller problem and the cars I looked at while shopping ran without problems.

Old wives tale or not, you decide......

[Kamil]

Thanks sweetwater!!!
Nice explonation. :)








BTW, I dunno, but when I see your screen-name I wanna say "sweaterwearer" :) No, i dunno why... yea, I'm a lil weird :p

[winfred]

i just went through this with a customer, they hook the car to the computer and it looks at the ignition burn time across the whole motor and decides if the motor needs to be torn down and inspected, this is not a entirely accurate way to tell the condition of the motor, without a tear down. the dealer told a customer of mine that their 94 740il's 150k nic motor was toast, on further inspection by me the motor had less then 12% leak down cold so i looked into the dealer procedure, and laughed, the whole problem with the car was a dieing fuel pump and the computer over compensated and made the car run bad till the computer had it's memory wiped and started fresh then it ran fine (till you put it under load then the fuel pump would show it's self)


BMW policy checks compression first, then performs a leak down test if compression results indicate a potential problem

[Bruno]

They have the nikasil linings, but I didn't know if they had problems with high sulfur gas like the M60 engines.

It looks like the US market received a cast iron M52 engine and the rest of the world an Aluminum Block with nikasil treatment.

That would explain why you hear about M52 nikasil only in UK message boards.

Seems like I am safe and I can invest into a M52 where I will pull the head out and install my M50 head...

If I can get the wiring and DME, I might even retrofit the Vanos.... SWEEEEET

[Sweetwater]

i just went through this with a customer, they hook the car to the computer and it looks at the ignition burn time across the whole motor and decides if the motor needs to be torn down and inspected, this is not a entirely accurate way to tell the condition of the motor, without a tear down. the dealer told a customer of mine that their 94 740il's 150k nic motor was toast, on further inspection by me the motor had less then 12% leak down cold so i looked into the dealer procedure, and laughed, the whole problem with the car was a dieing fuel pump and the computer over compensated and made the car run bad till the computer had it's memory wiped and started fresh then it ran fine (till you put it under load then the fuel pump would show it's self)

You sound like a very good mechanic. Kudos

[632 Regal]

:d

[DueyT]

the sulpher as it combusts in the cylinder reacts with the moisture and turns into sulphuric acid which in turn eats the Nikasil coating on the top of the cylinder bore causing the rings to leak at TDC. This in turn lowers the static compression and when real bad can cause a bad idle to a non start condition.

Neither me or Duey believes this old wives tale but there are people that swear by it.

I personally like the smell of Nikasil in the morning where all the Alusil people simply miss out on such a phenominal event.
Bang on, Jeff! If someone wanted to, they could get a borescope and look inside a cylinder through an intake (or exhaust valve) and look at the uppermost portion of the cylinder wall to verify its condition. As Jeff noted (and Sweetwater), the hydrogen sulphide (H2S) mixing with water vapour turns into sulphuric acid, H2SO4, and pits the upper portion of the cylinder wall (that doesn't get a protective sweep of oil below the rings...)

I think the problem wasn't as apparent on the Beamer bikes since most riders used higher octane gas with a generally higher-refinement / lower sulphur level.

Duey