Help! Is this a M52 Crank?

[E30-TourZing]

Hello All!

I received a free motor over a year ago that I was told to be a M52B28. I kept this motor on the back burner and then rushed to get the crank and rods removed before I moved to another home. I gave all other parts away and sent the remaining to the metal recycle without inspecting the block #'s to confirm if its a 2.8L. Rookie of the year move...

Anywho, I am going to bring my block to the machine shop next week and I want to confirm that my crank is 100% an 2.8L crank.

I have been looking all morning to line up the casting numbers and the painted numbers without a solid result.

Pictures from other M52 crank ID threads have not given me a lot of confidence either.

I am fairly confident I can guarantee its forged.

Here is the Painted number on the Crank - 171 198

Cast # on Crank - 143 2274

Is this a M50 Crank or M52?



Any help from this wonderful community would be much appreciated.

Thank you!

Jan -

[e30sh]

M20's have a 75 or 81 on them to identify stroke. Does it have an 84 somewhere?

[digger]

Measure the stroke it can be done with steel rule and square with blocks of dressed unwarped timber noting that you don't need absolute precision to within a mm to differentiate between the various cranks

[ForcedFirebird]

m50 cranks won't have the reluctor ring bolted to the back of it - that at least tells you if it's an OBD2 crank or not (CPS is in the block on them, not the timing cover - unless it's a Euro market early m52).

As e30sh said, the m20/m50 cranks have "hub75" (or 81) cast into them.

I just went out to the storage area and looked at an 84mm crank and it has 143 2277 cast into it, but I have never had luck with the casting numbers as identification.

[SkiFree]

Casting numbers can be used to identify the stroke. I have the dubious privilege of identifying hundreds of 6-cylinder M20/M5x/S5x cranks over the years and made a spread sheet correlating the casting number to the stroke. Unfortunately I left that digital paperwork at Ireland Engineering, but will try to see if they'll send it back over.

For US cars the following holds true in regards to 84mm stroke cranks:
crank #1748751, (E36 328i, and E34 528i ).
crank #1432277, ( E46 323i and E39 528i's ).

[ForcedFirebird]

Casting numbers can be used to identify the stroke. I have the dubious privilege of identifying hundreds of 6-cylinder M20/M5x/S5x cranks over the years and made a spread sheet correlating the casting number to the stroke. Unfortunately I left that digital paperwork at Ireland Engineering, but will try to see if they'll send it back over.

For US cars the following holds true in regards to 84mm stroke cranks:
crank #1748751, (E36 328i, and E34 528i ).
crank #1432277, ( E46 323i and E39 528i's ).

e34 528i? Also, wasn't the e46 323 a 2.5l?

I bet members here wouldn't mind if you shared said spreadsheet. ;)

[E30-TourZing]

Thank you all for your help. Unfortunately... the stamp 'Hub 75' is imbedded into the crank. It did have a reluctor ring attached, that I have removed way back when, but the ID number do not come together with what has been listed above. I also cannot seem to line up the numbers with other searches online, so my guess is the crank I have is from an M50.

Thank you all for your help. I will now scramble to find the correct crank shaft to complete my 3.0L M20.

[ForcedFirebird]

If it had the reluctor, it's an m52 crank, but an m52b25, not b28.

[E30-TourZing]

Hello all! I have been struggling to buy a E36 M52B28 crank.

I have found two options of E46 M52B28 TU crank. Will that work for my M20? It should be a direct swap from my understanding, but I just wanted to get expert opinion before I go ahead and buy a motor to swap the parts from.

Thank you all in advance!

[zaq123]

e34 528i? Also, wasn't the e46 323 a 2.5l?

I bet members here wouldn't mind if you shared said spreadsheet. ;)

I think 323 was a typo on his part

here is1432277 crank, 84mm stroke

[digger]

Hello all! I have been struggling to buy a E36 M52B28 crank.

I have found two options of E46 M52B28 TU crank. Will that work for my M20? It should be a direct swap from my understanding, but I just wanted to get expert opinion before I go ahead and buy a motor to swap the parts from.

Thank you all in advance!

Yes it does work but some mods are required possibly depending what rods and Pistons

[shawshankNG]

I think 323 was a typo on his part

here is1432277 crank, 84mm stroke

I love this forum.

[hasa]

I had to turn some amount off from the counterweights when installing a 84mm M52B28TU crank to M20 block. Counterweights touched block and pistons. And of course crank needed balancing after machining.

[shawshankNG]

Looks like the most popular M52 2.8L crankshaft casting numbers are:
1) 1432277
2) 2242898
Although there is a diesel M51D25 and S50 2.5L engine crankshaft with this same 2242898 casting number so you probably need to ask what engine the crank came from if you find one with this number.

Now to my question. I got two M52B28 single VANOS engines with the following block ID stamps and crankshaft numbers:

Engine A:
31358497
28 6S 1
2242898, C38 (crankshaft cast numbers)

Engine B:
33851209
28 6S 1
1439413, NC38 (crankshaft cast numbers)

I have not come across this second 1439413 casting number anywhere on the internet and it does have some physical differences with the popular 2242898 one pictured side by side here. I am 100% sure this is from a 2.8L M52 single VANOS because I removed them myself on the same day.

Question 1: Is it possible for the counterweights to be different in shape/placement but have the same 84mm stroke?

Question 2: Is the condition of the first crankshaft good enough to reuse?


Engine A block


Engine B block


Engine A crankshaft


Engine B crankshaft

Both crankshafts side by side. 2242898 on top.

[digger]

there are different versions it looks like your Crank A does not have the moninting for trigger wheel so this might be the smaller counterweight version which is the one to use