How do I know I am looking at an M52B28 motor?

[TOPSPEED]

More importantly, I am after the crank so it is important for me to make sure it's the 84mm one.

The things I know .. motor is out of a car and seller has no idea what car it came out of. It was bought to repair a motor in his E39 98 528i.

The stamps I can see ...
Engine block has a 1748933 as well as a symbol (that looks like an OPEL logo sideways) with an 84 following it.

The crank has a part number stamp on it with 1714481.

I thought there was a place on the crank that states the stroke. I am building an M20 stroker here and don't want to be buying stuff I won't be using.

[Farbin Kaiber]

So it's not assembled? You should look for a plastic cap on the oil filter housing, as well as a plastic valve cover. If the head has not been replaced, the VIN tag on the back of the head ma also be helpful.

[TOPSPEED]

and what should those say? the oil filter housing or the valve cover ...

[Jean]

They would tell you they are plastic.

[Kerrath]

Farbin's suggestion of trying to find the tag would be your best bet, but otherwise...
I googled the # for the crank and found this:

http://data.bmrparts.com/bmwparts/7165406024872U.html

Seems to be from a B25 engine.

What farbin meant by the plastic valve cover, I know. On the engine, the valve cover should be plastic rather than aluminum if it's a B28. You'd have to take the plastic cover cover off to find out I think. Same thing with the oil filter housing, it'll have a plastic cap if its from a B28. Others had aluminum.

The # for the engine you gave appears to be a B28. This is the engine that crank is going into? Or the engine it came from?...

[lifeiskaos]

plastic valve cover and oil filter cap dont mean it's an m52b28. it could be an m52b25... find the vin and look it up

[TOPSPEED]

Farbin's suggestion of trying to find the tag would be your best bet, but otherwise...
I googled the # for the crank and found this:

http://data.bmrparts.com/bmwparts/7165406024872U.html

Seems to be from a B25 engine.

What farbin meant by the plastic valve cover, I know. On the engine, the valve cover should be plastic rather than aluminum if it's a B28. You'd have to take the plastic cover cover off to find out I think. Same thing with the oil filter housing, it'll have a plastic cap if its from a B28. Others had aluminum.

The # for the engine you gave appears to be a B28. This is the engine that crank is going into? Or the engine it came from?...

Well, and as per Bavarian Auto Recycling:

http://www.bmrparts.com/engine1a.htm

It's a 96-98 528i motor if you go by the block stampings.

The head, as far as I remember, had an aluminum valve cover. And I've also seen a stamp that had a 2.5 on it ... which confuses me even more!

The crank from this mystery engine is going into my M20 block.

[lifeiskaos]

Well, and as per Bavarian Auto Recycling:

http://www.bmrparts.com/engine1a.htm

It's a 96-98 528i motor if you go by the block stampings.

The head, as far as I remember, had an aluminum valve cover. And I've also seen a stamp that had a 2.5 on it ... which confuses me even more!

The crank from this mystery engine is going into my M20 block.

awesome... :roll:

how about i sell you my m52b28 crank? :pimp:

[TOPSPEED]

awesome... :roll:

how about i sell you my m52b28 crank? :pimp:

Does you crank have a stamp on it somewhere that says that it's an 84??? I've seen a pic of a one somewhere and forget where I've seen it.

[lifeiskaos]

i'm not sure as the crank is still in the block on my engine stand, but i can guarantee (100% money back) you it is an 84mm crank as the engine was from a 98 328i, i pulled it myself. if you want it i will take it out of the car and look up any numbers stamped on the crank for verification.

[Mitch M]

DS of block @ oil pan gasket has stamp 28 6S...28 for 2.8 liters...6 for 6 cylinder. Crank should have H84 stamped into the counter weight. If head is original, u can always run VIN...sticker on back of head.