How the Frankenmotor Became an S50

[FredK]

Where'd you get the rings, just curious?

[triggrhaapi]

What rings are you using, Schoettle, Deves or something else?

OEM so I would imagine they are Mahle or something of that kind. I'll post a picture when I get them later today.

[FredK]

What rings are you using, Schoettle, Deves or something else?

[triggrhaapi]

Didn't get parts yesterday, so I prepped the chassis!!! Hooray for me and Joe!!


Here are a few shots of the cleaned up engine bay.




Here's a shot of the freshly installed IX brake booster and master cylinder.


Here's the shot that shows the mounting bolts and nuts for the IX booster. Pain in the motherfucking ass to get to. Joe had to contort and fold himself into Samus' Ball form to get them undone and redone.


Here's some shots of some of the new leather ///M stitched goodies I got...




One more shot with some foreshadowing. I hear that makes the story more interesting.

[triggrhaapi]

Still waiting to get upper rod bearing shells and piston rings, along with other essential engine parts. Until then, I've installed the crank and torqued the main bearings.

First, you need to install the oil squirters back into the upper bearing in the crankcase. This is how they look installed:



In case you're wondering, this is what they look like when not installed. They are about ten bucks each and hard to find so I recommend not losing them.


Here's the freshly polished crankshaft. It will soon be covered in grease and not pretty, so I thought I'd take a shot of it in it's glorious state.


Here is the block, now turned on my engine stand so I can drop in the crankshaft. On it you will see the as yet unopened bearing shell set for the main bearings.


First we lubricate the bearing shells and then press them in. The ones for the upper bearings have two holes and can only be lined up one way. The thrust bearings, the larger two bearings, go on the second bearing from the back of the motor, between cylinders 6 and 5. They can ONLY be placed here, as the crankshaft only has thrust bearing surfaces on this bearing.


Next we place the crankshaft into the block and lubricate it, turning it once 180 degrees and lubricating it again with assembly lube. We also install and lubricate the lower bearing shells keeping in mind that there is a specific thrust bearing cap. Once these are all done, place them and thread the appropriate bolts. In my install, there is no pickup tube support bracket, but there is for E36 versions of this motor, you can ignore this bracket if building for an E34 or E30, as the pickup tube is shorter and needs no bracket.


Now we need to torque down the main bearing caps. Just so all of you know, this is NOT covered in the bentley manual. I had to go searching to find the appropriate torque specification. Torquing is two stages, the first is 20 nm, then a torque angle of 50 degrees. This means that you torque it first to an initial spec and then turn the bolt an additional 50 degrees.

We're done for now. Hopefully the parts will be in and the build can continue as planned today. I will be covering piston to rod installation, as well as piston and rod install to block, oil pump to block and crankshaft, and time permitting, cylinder head to block installations. I'll be covering this whole motor build documented every step from parts to completion.

[triggrhaapi]

M50 block was tapered, so I decided to bore it out and use S50 pistons and just make the damn thing an S50. I got my S50 pistons as a mix and match set for around $400, far cheaper than $1000 for JE or factory oversize M50 pistons, which wouldn't have fixed the taper anyhow.


Let the glamor shots begin!


Oh and that's the red devil himself minus one M20 motor. Bimmerfest or BUST!!!


That used to be an M50 block, once upon a time, but now, it's an S50 block, and those pistons didn't used to match either. I had them balanced and the wristpins polished.


More automotive porn.


One more shot with my dirty garage couch, on which I smoke hookah and/or store parts. One day it will be a porch couch, but that will have to wait until I'm sure the rainy season is over.

/Porn. More to come soon, with assembly and some more shots of the little red E30 hooptie!!