The complete repair, rebuild, repaint, and v8 swap of my early model sedan

[JGood]

Got everything finished up. The interior is so much quieter now. The exhaust actually sounds louder, only because so much of the engine noise was removed. Sealing up the firewall and adding the factory dash insulation made a huge difference. All you hear is the exhaust behind you, and an overall "growl" sound from the front under load. Before, it sounded like the engine combustion was actually happening on your lap, which isn't the most pleasant sound in a street car.

I really like the grey carpet. It adds a nice contrast to the black everything else.






Need to figure this gap out. I'm guessing it's due to being a coupe seat in a sedan?

[Jean]

Nicely done ! Since the rear seat bottom from a 4 door is more rounded off in the corners and you have one from a 2door you have overhang and maybe that’s what causing the gap ?

[JGood]

My paint started looking pretty beat. I've been waxing it twice a year or so, but it hasn't been buffed since it was sprayed 7 years ago (yes, it's been 7 years... holy crap).

I've never done any type of buffing, nor do I have a buffer or D/A, nor do I want to learn on this particular paint job. So after some research, I settled on the Meguiars DA Power System. It's simply a dual action attachment that goes onto a corded drill, with a 4" pad. It doesn't spin fast enough to burn paint, but spins fast enough to remove 90% of paint damage (well, in my case anyway). Also, it's only $40.

So I went over the whole car with a clay bar, then did compound with a red pad, followed by polish with a yellow pad, then waxed it with my 10" orbital. I know none of this is high end professional level stuff, but I am VERY happy with the results. I haven't seen the gold flake shine in my paint in years, I almost forgot about it haha.








I was so excited to drive it to work the next day. Get in, passenger window won't go down. Start driving, my oil pressure gauge pegs at zero. After pulling over and confirming I have oil, and pressure, I continue on my way. Get to work, central locking is dead, have to go lock all 4 doors manually. WTF! All I did was clean the paint and everything broke.


So I tore into the central locking last night, and after a few hours of testing with inconsistent results, I determined that the ETM is wrong. Power to the central locking module actually loops through the C405 door connector like on late models, contrary to the schematics for 85's. My c405 is jacked, I already have my power window hardwired through the connector, bypassing the pins, because the connector is shot. So I spliced the power to the central locking, bypassing the door like most people do. I need to buy a new connector and repin it, which is going to be an expensive PITA. It's such an uncomfortable place to try to do wiring, and the pins are expensive as hell.

My oil pressure gauge randomly started working again, and my passenger window works after opening and closing the door (which confirms that c404 needs repinned as well, ugh.)

[JGood]

My power steering has been leaking, as they all do eventually, so I finally decided to replace the hoses and reservoir. Mine is a bit of a cobbled together setup, using male barb banjo fittings. The hoses I used for this are Gates 5/8" power steering hose 350030 (very very close to 16mm) and BMW 12mm power steering hose 32411131524. I couldn't find just a plain 16mm power steering hose from BMW, they all had a metal end crimped on, which sends them up into the $50+ range. The difference in quality between the two hoses is substantial though, the BMW hose seems much more solid.


Old leaky junk, and new junk.




Hoes:






DEI fire sleeve, since the hoses are about 1" from the drivers side exhaust manifold






Ready to go:





BMW power steering reservoirs have filters built in. Admittedly, I don't know what they should look like when new, but I can't imagine it's anything like this. I had to break it to remove it, but I took a piece and held it up to light, and could not see any light through it. How a constant flow of thick fluid got through there, I don't know.

[e30RS]

Fantastic build thread, love the paint color.

[dmjensen]

Definitely replace that reservoir. The filters in the new ones are similar to a fuel pump filter where is like a big cookie sock in the bottom of the tank. Also I don’t know how your fitment is but an e90 era reservoir has the hose barbs at a 45 degree angle instead of straight down. 32416851218

What I’ve been seeing happening to our cars is either they run out of fluid from leaking and start whining or they get so much crappy fluid in the system that they whine. I’m only assuming it’s from overheating the fluid over time but when this happens it introduces tiny metal shavings into the system. I always replace the reservoir whenever replacing other components.

[JGood]

Yeah, the reservoir in the pics is the new one, already on the car. I just took the old filter out to look at it.

And yes, cavitation wreaks havoc on pumps. I went through multiple fuel pumps on this car due to cavitation, before I finally figured it all out. Mine wasn't making any noise or showing any failure signs, which is surprising. 340k miles and 34 years of used ATF flowing through that filter... Although I have swapped many racks, pumps, etc in my 18 years and 240k miles of ownership, so it got new fluid often.

[JGood]

It's about 95 degrees here, so I figured it would be a great time to take apart all of the everything.





Just kidding, this is not what I want to be doing. My rear main seal began leaking a lot of oil. The 6 speed trans can't be removed with the engine in the car, there's no way to get to a few of the bolts. So, everything had to come out. New seal is in, and tonight the engine will go back in. Fingers crossed that this fixes it, because I do NOT want to do all of this again...

[TeXJ]

eww

[jeenyus]

DANG! i'm sorry man. I understand the feeling of only being able to go forward even though it's not what you want to do. glad you fresh at it though.

[JGood]

Got the car back together, went for a test drive, everything is dry so far.

A little more info:

The old seal was an SKF, which is OEM(ish). It was a tight press fit when I installed it 5 years/30k miles ago. When I removed it, it was loose as could be. I could literally push it straight through the housing with my fingers.

Proof:

https://www.youtube.com/watch?v=-_5bqJHJm7c

No idea what happened there. Not wanting to do this again, I ordered part number 11141436109, which is a rear main seal "kit". This comes straight from BMW with a new housing, with a seal pressed into already, in addition to the seal gasket, and hardware with gasket washers. It's $130, vs. just the $15 seal, but considering the massive labor in removing an m6x/g420 from an e30, the cost is insignificant. I had about 18 hours of labor into this, plus fluid replacement costs.






After a few days of doing some pretty significant work, which I haven't done in a few years, I have no idea how I built this car in 8 months back in 2011-2012. That was all night every night, and every weekend. I could never do that now, my body can't handle it.

[efficient]

i was wondering about this car earlier today.

[JGood]

I'm having a bit of an issue, and I could use some assistance troubleshooting.

I have a vibration, I believe from the rear of the car. It ONLY happens under throttle, at higher speeds (50+mph). Only happens in gear (any gear), under load (say, 1/2 throttle or more). The engine is silky smooth revving in neutral, and as soon as I lift off the throttle at higher speeds, all vibration stops. I would best describe the actual vibration as what a CSB that is just starting to go bad feels like, when you accelerate from a stop (obviously that isn't my symptom, just the best thing I can compare the actual vibration feeling to). You sort of get that deep muffled noise as well, the sound of something out of balance shaking the car.

Those symptoms lead me to believe the following are non-issues:

• Anything with engine/flywheel/clutch: This would be present during neutral revving as well, also not MPH dependent
• Wheel/tire issue: This would be present during off-throttle
• Wheel bearings: No noise/vibration while cornering, also would not be throttle dependent
• Brakes: Touching the brakes while full throttle does not change the vibration
• Driveshaft balance: Wouldn't be throttle dependent

I have a brand new OEM Guibo and CSB, driveshaft was rebuilt and has maybe 40k miles on it. Guibo/CSB usually only cause low-speed issues as well. I have checked them anyway, there is no play anywhere, everything is tight and looks fine (they should, OEM and maybe 3k miles).

Rear diff bolts are tight, new poly diff mount, chassis mounting tabs not torn.


My only thought is the CV joints. I have CA Tuned HD axle shafts. Can CV joints fail in a way to cause these symptoms?

[TeXJ]

I wonder if your rear diff is having issues?

[JGood]

I thought that too. So, today I swapped in my spare diff. No change. Doh!

Also, while test driving, I noticed that it doesn't even take half throttle to make it vibrate. Really, any throttle at all above 50mph causes the vibration. I *think* it smooths out, at least a bit, over 80mph. Not a lot of places I can easily test that.