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

TopSpeed · 03-24-2009, 11:13 PM

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.

e30_kid89 · 03-25-2009, 01:22 AM

The crank should have a blueish color to it. That's how you know you're looking at the forged 2.8L crank.

Eurostyle · 03-25-2009, 01:38 AM

"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."

Buy from someone relable!

If they dont even know what car it came out of, what tells you how the engine ran...milage, etc etc etc...So many unknows, to save a few bucks...

TopSpeed · 03-25-2009, 07:08 AM

I am not buying a motor ... just a crank.

The thing will have to go to a machine shop anyway and to top it all off ... it's cheap! Like I mean, really cheap.

This is suppose to be a budget build ... if I was going to throw mad money on it, it would have an M30.

Bullet Ride · 03-25-2009, 08:17 AM

Well you know that the stroke is supposed to be 84mm... so measure it.
Take it to a machine shop and put it on a set of v-blocks and use a height gage to measure the distance between centers on journals that are 180 degrees apart. You should also get a the journals measured as well to see what kind of shape they are in.

simplycars · 03-25-2009, 11:35 AM

Part number on the engine corresponds to
528i 96-98 MaxSil™ 1748933 / Tefcote™ 191 hp @ 5300 rpm 206 lbft @ 3950

simplycars · 03-25-2009, 11:36 AM

OEM Number: 1714481
Manufacturer: BMW Casting #

This BMW part works for the following BMW models and certain year ranges:
1990 1991 1992 1993 1994 1995 BMW 325is 2DR ( E36 ) BMW 325i 4DR ( E36 ) BMW 325i CONV ( E36 ) BMW 525i 4DR ( E34 )

simplycars · 03-25-2009, 11:39 AM

84mm bore / stroke - 1995-1999 E39 528i - m52b28

TopSpeed · 04-06-2009, 06:42 PM

After sending the crank to a machine shop, I get the bad news ... it's a 75mm crank! Not the 84 I am after!!!

Just wondering how a block out of a 97 528i has a crank out of a 325/525! Based on part numbers alone after cross checking with RealOEM and a dealer parts guy that's what I found out.

Bullet Ride · 04-06-2009, 08:05 PM

Half-ass way to do a low compression build