1993 BMW E36 Street and Track Build - Refurbishing Parts
Well, there are lots of parts on a car, not all can be replaced with new parts and still be within budget. So, parts need to be refurbished in order to keep a project feasable. Follow along and check out the progress on parts refurbishing!
The engine purchased from the previous owner at a claimed 75,000 miles, and then pulled from the green E36 5,000 miles after installation, making this engine a young 80,000 mile engine. The previous owner of the red E36 actually purchases BMW cars and ships them overseas, where foreign countries drive them until 500,000 miles. How does this happen? Well, in other countries, cars are maintained better, and things are fixed as preventative maintenance rather than waiting for failure to replace something, which could mean it’s too late to repair. Anyway, this engine has PLENTY of life left in it. As a preventative measure, the oil pan gasket was replaced, idler pulley and tensioner, AC and accessory belt, cooling hoses, fuel lines, and vacuum lines. All parts were replaced with OEM manufactured parts. If you are looking for an OEM provider, check out Advance Auto Parts, and ask to order your parts from WorldPac. They have EVERYTHING for your BMW. I even ordered an OEM shift boot and wheel center caps from them!
One common problem on the M50 motors is an oil leak from the oil filter housing, both between the housing and the engine block as well as two coolant blocking caps that were for optional cooling on other cars, such as the M3. The gasket that was removed had lost any attributes of rubber, and was almost plastic feeling. The o-rings that were behind the caps were similar, so all rubber was replaced here.
This is the oil filter housing reinstalled, along with a new belt tensioner.
After pulling the engine from the red E36, the engine bay was definitely in need of a bath. The car has 105,000 miles, and is 23 years old now, so you can safely assume that some cleaning would be necessary!
The front suspension from the green car was torn down and cleaned up. The front control arms are Meyle heavy duty pieces, and only have around 10,000 miles, so they can be reused. The bearings are Timken and have about 15,000 miles. The sway bar has around 500 miles, and the Bilstein struts and springs have around 30,000 miles, but drive just as well now as they did when new. The subframe knuckles have 150,000 miles to my knowledge and have plenty of life left. The steering column may have the same age as knuckles and subframe, but after a little pressure washing, you’d never know!
The front control arms were degreased and then painted gloss black to keep them looking new for years to come.
The front subframe and control arms were then painted gloss black to keep them looking new, and ease the cleaning process in the future.
A pile of parts were ordered for the rebuild. Almost everything is OEM. Of course, much more parts were ordered after this picture was taken as well.
After tearing into the steering rack, which already has very new inner and outer tie rods, it is evident that this has plenty of life left. All of the internals were very clean. New boots and clamps were installed to keep the elements out, and it was cleaned up and ready to be put back into service.
Some high pressure water and Simple Green can really clean a dirty engine bay up quickly! Here is the engine bay after a little pressure washing.
The E36 seldom was equipped with a limited slip differential (LSD). However, certain earlier models (1996 and older) came with LSDs in 325is cars with a winter package, meaning they have seat warmers. Well, the red car had seat warmers, and was, indeed, a 325is. To my surprise, it actually has an LSD!! For those that do not know, and LSD allows the power from the driveshaft to be driven to both rear wheels rather than one, in a standard car with an open differential. However, and LSD has a clutch pack, allowing your outer wheel to still spin faster than your inner wheel on a turn. Now, with that said, the red car came equipped with an automatic transmission, which come with a 3.91:1 final drive differential, where as a manual car would come with a 3.15:1. This means the engine will be spinning faster than with the proper ratio with the same tire size. This means more power off the line, but possible lower fuel mileage, and lower top speed. Top speed does not concern me, however fuel mileage does. If this gearing decreases fuel economy greatly, I will use the LSD and swap it into my 3.15:1 differential to retain stock gearing, yet have the features of the LSD as well.
One thing I wanted to keep from my old differential is the poly bushings I installed not long ago. A simple differential cover swap took care of this right away. The differential cover doubles as a differential mounting bracket.
If you own an E36, your rear shock bump stops are most likely an orange dust attached somewhere between the shock boot and the shock mount. Mine was no different, so new shock bump stops were installed. The factory rear shock mounts were retained, because they seem to be fit to perform their task.
The rear differential was painted, because it was so ugly, and it was reinstalled along with all the rear suspension components.