I've been rebuilding a M50 that I plan on putting in my E30. I'm in the process of measuring the bearing clearance for the main and rod journals. As far as I know, main bolts and rod bolts are TTY and I seemed to have lost/thrown out the old bolts. If I use new bolts to check the clearances, can they still be used in assembly? Do I need to fully torque down the bolts to get accurate measurements? Any help would be greatly appreciated.
M50 Rebuild: Bearing Clearances
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I've been rebuilding a M50 that I plan on putting in my E30. I'm in the process of measuring the bearing clearance for the main and rod journals. As far as I know, main bolts and rod bolts are TTY and I seemed to have lost/thrown out the old bolts. If I use new bolts to check the clearances, can they still be used in assembly? Do I need to fully torque down the bolts to get accurate measurements? Any help would be greatly appreciated.
I'd see if there's someone willing to send you a set of old bolts, or find a yard and pull all those bolts out, or just buy a full 2nd set. -
Damn, I was hoping to avoid that as they are $150 for each full set. I have another complete M50, but I didn't want to take it apart until I got this one back together. Since they sell both bolts individually, I think I'll buy two extra of each and sacrifice them to get the measurements one by one. That would work right? Regardless, thanks for the feedback.Originally posted by MelonEngine work takes patience and finesse.
Suspension work takes anger, a big fucking hammer, and a torch.Comment
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Damn, I was hoping to avoid that as they are $150 for each full set. I have another complete M50, but I didn't want to take it apart until I got this one back together. Since they sell both bolts individually, I think I'll buy two extra of each and sacrifice them to get the measurements one by one. That would work right? Regardless, thanks for the feedback.Comment
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And you could also use regular m10x1,5x75 grade 10.9 bolts that can be get from any bolt store.Comment
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A regular m10 grade 10.9 might be usable, but I'm not sure I would trust the quality compared to oem. Maybe I'm just paranoid.Comment
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I'm looking into this actually as well.
I've found the rod bolts for ~3.50 each on autohausaz.com, but the main bolts are ~7ish each. Are the M54 main and rod bolts the same as the m50?Comment
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I don't know where you're finding those prices, but send me a link! Good looking out with those main bolts though. Do you know how ARP head bolts are? I guess I could use the M10 10.9 bolts to get the measurements but I wouldn't put them in the engine. (I'm paranoid too.)Originally posted by MelonEngine work takes patience and finesse.
Suspension work takes anger, a big fucking hammer, and a torch.Comment
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Dunno where you bought the main bolts from but the best price I found was $7.50 per bolt x14 = $105 for the set. First I've heard of the distortion.. good to know.
A regular m10 grade 10.9 might be usable, but I'm not sure I would trust the quality compared to oem. Maybe I'm just paranoid.
Did you check the bearing clearnces with the arp specified torque? I have heard that it's quite common.
And the oem main bolts are just regular bolts. So you can get those from bolt store. Just make sure those aren't some cheap chinese ones where the grade is ofter totally different than it should be. The rod bolts are bit special so those need to be oem.Comment
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I order my parts from bmw part stores at germany.
Did you check the bearing clearnces with the arp specified torque? I have heard that it's quite common.
And the oem main bolts are just regular bolts. So you can get those from bolt store. Just make sure those aren't some cheap chinese ones where the grade is ofter totally different than it should be. The rod bolts are bit special so those need to be oem.
I didn't do the ARP mains in my build so I didn't measure with them.
Again, good to know about the oem mains being able to use a quality m10 10.9 bolt. For anyone looking for a good source, you can order from mcmaster carr, m10x75mm (assuming 1.5 thread pitch) is $10 for 10 bolts. Belmetric also has assorted sizes and grades, their m10x75 10.9s are $1.29 ea https://www.belmetric.com/10x15-coar...io1l9bdgbdjs76Comment
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Maybe Offtopic but I'm not aware if there is problem of ordering stuff from germany to US. At least the shipping from US to europe is quite reasonable priced. And many sellers offer world wide shipping.Comment
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Ahh just saw you're in Finland. I guess ordering from BMW parts stores in Germany is cheaper? Lucky you!
I didn't do the ARP mains in my build so I didn't measure with them.
Again, good to know about the oem mains being able to use a quality m10 10.9 bolt. For anyone looking for a good source, you can order from mcmaster carr, m10x75mm (assuming 1.5 thread pitch) is $10 for 10 bolts. Belmetric also has assorted sizes and grades, their m10x75 10.9s are $1.29 ea https://www.belmetric.com/10x15-coar...io1l9bdgbdjs76
Possibly. Apparently the M50 uses two different types of rod bolts, one of which is used on the M54. Its part#11241739728 which is where I think you're getting the $3.50 from. Unfortunately, I need the ones that are $7.50 each (part#11241713342).Originally posted by MelonEngine work takes patience and finesse.
Suspension work takes anger, a big fucking hammer, and a torch.Comment
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:shock: Yeah, I did the same thing with the lifters in my M50. I'm sure there are other things that are supposed to retain their placement as well but I've come to the conclusion that it'll be fine.Originally posted by MelonEngine work takes patience and finesse.
Suspension work takes anger, a big fucking hammer, and a torch.Comment
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