M52 iron engine

[Fireball1991]

Hi there!

I wondering, is it true or false...

So the statement: some of M52 engeins made by iron.

if it's true, what about the serial numbers? how can i know, is it alloy or iron? can i detect this with my block's serial number?

thanks a lot!

[ultimatetester]

American blocks should be iron to counter the high sulfur in the petrol. Others should be Aluminium

The m52tu has steel liners only

You can detect this with a magnet

[pbonsalb]

Z3 in the US had aluminum blocks so I am not sure sulpher in the gas is a problem.

[ed323i]

All European M52 engines are aluminium. One big advantage is that they weigh approx. 30kg less than the M50/M50TU or US M52 engines. That makes the car a bit more nimble, and gives a bit less understeer. You can double check with a magnet, like ultimatetester wrote, but unless your car is imported from the US, you can be certain it's aluminium.

A disadvantage is that the chances of damaging the engine block are a little bit higher. When it overheats seriously, besides the head(gasket) cracking, you might run in trouble getting the head bolts to hold.

[jmo69]

Z3 in the US had aluminum blocks so I am not sure sulpher in the gas is a problem.

High sulfur fuel reacted badly with the Nikasil alloy engines unless they had the steel liners.

[pbonsalb]

Wasn’t that an issue for early 1990s aluminum V8 blocks, and not an issue for the late 90s aluminum 6 cylinder M52 block? After all, BMW sold that aluminum M52 block in the US in Z3s. This is the first time I have read of someone saying this block has US fuel related problems.

[ultimatetester]

Wasn’t that an issue for early 1990s aluminum V8 blocks, and not an issue for the late 90s aluminum 6 cylinder M52 block? After all, BMW sold that aluminum M52 block in the US in Z3s. This is the first time I have read of someone saying this block has US fuel related problems.

It didn’t, because it had iron liners. You won’t read about those problems because the m52 are either iron and the m52tu is Aluminium but has iron liners so the issue never existed in the blocks. The reason WHY the us m52 is iron is because of the sulfur. So not surprising that there’s 0 complaints about this because bmw already took it into account when designing the us version

[pbonsalb]

The M52TU is a different motor than the M52. All M52TU have aluminum blocks. We got them in the US in E46 328i and E39 528i from about 1999-2000. Then the M54 appeared.

This discussion is about the M52, which is an older motor available in both iron and aluminum block versions. Are you saying that the aluminum Euro version is different from the US aluminum version, in that the Euro one has Nikasil sprayed liners and the US one has iron liners or sleeves.

[ultimatetester]

The M52TU is a different motor than the M52. All M52TU have aluminum blocks. We got them in the US in E46 328i and E39 538i from about 1999-2000. Then the M54 appeared.

This discussion is about the M52, which is an older motor available in both iron and aluminum block versions. Are you saying that the aluminum Euro version is different from the US aluminum version, in that the Euro one has Nikasil sprayed liners and the US one has iron liners or sleeves.

The US M52 is iron. The US M52tu was Aluminium with iron liners. That’s it.

The Euro M52 is Aluminium all the way.

The reason behind the whole redesign of the US M52 is the sulfur level of the fuel in the US.

[pbonsalb]

The M52 in the US Z3 is aluminum block, while the M52 in US E36 and E39 is iron block. Is there a difference between the aluminum M52 in the US Z3 and the aluminum M52 in European BMWs?

The M52TU is a different motor with a different block and head that is not relevant to this discussion about M52.

[ed323i]

This video explains it all.. The aluminium M52 was sold as nikasil version (outside the US) and as iron sleeved version (late versions US Z3 I think):

* Turn on the the subtitles..

So, this summarizes it all, BMW produced three different M52 blocks:
* M52 aluminium nikasil block; non-US market
* M52 iron block; US high-sulphur-gasoline market
* late M52 aluminium with iron sleeves US Z3 (seemingly also late European M52, perhaps mine also, would be nice)

[pbonsalb]

Ok. That is what I wanted to know. I wonder how much heavier the iron sleeved aluminum blocks are than the sprayed liner aluminum blocks. A few in the US have swapped the aluminum Z3 M52 into E36 to save weight, and some have also rebuilt it with M54 3.0L internals for more displacement.

[ed323i]

I seem to remember it's 30 kilograms difference. So, that's something you definitely notice. Those minus 30kg will make the car feel a little nimbler while steering, and produce less understeer in fast corners. And it improves acceleration (and also brake) times. Based on my experiences 30kg is something you can definitely feel.. Same as difference between full and half-full tank (or half full and almost-empty tank). Center of gravity of those 30kg (vertically and horizontally more or less in the center of the engine block) is not too high, but also not very low. So it also affects handling a bit. Fuel tank is at a lower point.

Update: I found a link with weights:
Here it says the M50B25TU weighs 198 kg, while the alu M52B25 weighs only 166 kg. So 32 kg difference. Assuming the US iron M52 weighs the same as the M50TU (Vanos).
This guy weighed both bare blocks, an E39 M52B28 iron block and an aluminium Z3 M52B28, and on his (not so precise) scale, he saw a difference of 52 lbs.

[Avineedsinfo.77]

All European M52 engines are aluminium. One big advantage is that they weigh approx. 30kg less than the M50/M50TU or US M52 engines. That makes the car a bit more nimble, and gives a bit less understeer. You can double check with a magnet, like ultimatetester wrote, but unless your car is imported from the US, you can be certain it's aluminium.

A disadvantage is that the chances of damaging the engine block are a little bit higher. When it overheats seriously, besides the head(gasket) cracking, you might run in trouble getting the head bolts to hold.

so a Canadian car would be an aluminium block? My example is a 1997 328i, and if it is aluminium do you know where I can find an iron block