S62 E30 AWD (Formerly: Fantastic V8 swap candidate)

[Aaron]

Legitimate question. So the pump mounts to where the whole runs through the middle, underneath, picture a lower case n if you will. How does the pump take fuel from both sides once the level drops to a point where fuel is split onto both sides?

My E34 has a weird tank too, picture a capital L shape. The first 3/4 of the tank drop really quickly, the last 1/4 seemingly lasts forever. And of course they didn't tune the gauge to compensate. Weird to see miles until empty read 600, but have a 1/4 tank left after just 200.

[The Dark Side of Will]

I'm sure it didn't help the worn out subframe bushings or control arm bushings or the non-serviceable rear driveshaft U-joint, either.

But it was fun.

[The Dark Side of Will]

Legitimate question. So the pump mounts to where the whole runs through the middle, underneath, picture a lower case n if you will. How does the pump take fuel from both sides once the level drops to a point where fuel is split onto both sides?

My E34 has a weird tank too, picture a capital L shape. The first 3/4 of the tank drop really quickly, the last 1/4 seemingly lasts forever. And of course they didn't tune the gauge to compensate. Weird to see miles until empty read 600, but have a 1/4 tank left after just 200.

That's part of what went wrong.
It works similarly to the way the Pontiac 6000 works. The pump is in the right lobe of the tank and the return line comes back into the left lobe. Inside the tank, the return line enters high, the drops down to the bottom of the tank, then goes up again to go over the driveshaft hump and discharges into the "swirl chamber", which is a ~4" high circular baffle around the fuel pump.
Where the return line is low in the left lobe, it has a venturi and a hole in the side. This acts like a Bernoulli or jet pump using the velocity of the return fuel stream to pull additional fuel from the left lobe of the tank to the right.

That's the newer 63 liter tank. The older 55 liter tank has a crossover tube that goes UNDER the driveshaft. This is easily damaged and complicates driveshaft removal.

[Aaron]

Ah that makes sense. Seems like both tanks have a lot of spots for potential problems, but it wouldn't need to be a Mercedes if the tank was simple. Then again, the Fiero tank isn't much better.

[The Dark Side of Will]

Yeah, the Fiero tank is quite sensitive to fuel slosh from acceleration and braking (and cornering, for that matter).

If GM had moved the front axle 5" further forward, the Fiero would have been a MUCH better car. That would have required ditching the pop-ups, would have gotten the wheel houses out of the footwells, allowed turning the occupants to face forward, allowed enlarging the front end of the center tunnel to become a true backbone and be tied in with the front frame rails, and allowed 2-3 more gallons to be added to the gas tank.

There are a few relatively simple packaging changes to the Northstar that would have made the engine MUCH better as well.

Oh well.

[Aaron]

My problem is I've overheated the fuel on several occasions now, leaving me stranded. Never had the problem with the 2.8l, but only my 3.4. So now I try to make sure I start with a full tank when driving anywhere over a half hour or so. One of these days I'll relocate the return, but I'm not sure when I'll care enough.

[Series8217]

Yeah, the Fiero tank is quite sensitive to fuel slosh from acceleration and braking (and cornering, for that matter).

Is this really true of Fiero tanks when the baffles aren't broken or missing? I corner >1.0G on the track and have run down to less than a quarter tank, and never experienced fuel starvation.

[The Dark Side of Will]

I've only ever had problems at less than 1/4 tank.

Maybe my understanding is flawed, but I thought E30's did better than that.

[The Dark Side of Will]

Got most of the front mail seal replacement done over the weekend.
On an M20, most of the work involved in front mail seal, timing belt and waterpump is the same, so this is a combined job that ended up being 2/3 preventative.
A previous maintainer had done the timing belt and front main and intermediate shaft seals... but botched the lower timing cover reinstall, damaging the main seal in the process. He also didn't clean ANYTHING while he had it apart, so the timing covers were full of the previous belt's wear fuzz, which became a very unique type of schmutz when combined with the oil coming off the main seal. Yay.
The timing belt I removed actually looked great... almost a shame to replace it.
The previous maintainer had no idea how to route the crank sensor and oil level sensor wires, so they ended up resting on belts or pulleys and getting worn. I have a new crank sensor, but the oil level sensor wires are part of the main engine harness, so they will have to be repaired (and re-routed!)
I forgot my camera, so only have cell-phone pics.
The tensioner pulley bearing was sketchy and I didn't have a replacement on hand, so I elected to stop once the new lower cover and waterpump were installed, and order a new tensioner.

Full takedown:


Most of the stuff that has to come off the front of the car to do this job:


Timing covers as removed; The bright streak is wear from a previous timing belt snafu that almost wore through the cover:


Lower front cover, covered in horrible:


Nasty old stamped impeller vs. new cast impeller goodness:


Trigger wheel and crank sprocket:


Intermediate sprocket, full of aforementioned schmutz


This may have been why the main seal was having problems:


Mangled main seal:


Bead blasted lower front cover with new seals:


Buhhhling! (you can see an almost crack in the upper cover where the belt was previously rubbing)

[The Dark Side of Will]

I found out from www.e30tech.com that the two slotted holes in the upper cover receive clips that hold a plastic channel which keeps the crank sensor and oil level switch wiring safe. The previous maintainer either broke or lost those and didn't or couldn't get new ones. I'm not going to bother... I'd rather re-route the wires so that they're easier to access anyway.

[The Dark Side of Will]

Fired and drove the car around the block last night... temp stabilized, so I think I have the cooling system bled.
There are two bolts that hold the upper timing cover, a 6mm and an 8mm. BOTH gave up their threads as I was reinstalling the cover. The 6mm went first. My dad didn't have a 6mm helicoil set, so we had to run up to Advance to grab one. AFTER I had repaired the 6mm hole and was reinstalling the cover, the 8mm hole gave up. Sigh. Fortunately my dad had an 8mm helicoil set on hand, so that one was much easier to repair.

The car is sans power steering for now, as there is an 8x22 bolt missing from the PS pump bracket, which means that the power steering only mostly worked before I took it apart. I'll get a replacement for that bolt and a new belt this week.

All three of the rack and pinion "adjusting bars" for the belt drive are stripped. I already ordered new ones for the Alternator and PS pump last week, but discovered the A/C comp adjuster was also mangled.

I removed the compressor and unbolted the bracket from the block so I could get the oil pressure sensor and oil level switch wiring out from behind the bracket. I tried routing them over the top of the engine, but there just wasn't enough wire. I cut them and will splice in some extra to route them over the top of the engine. I also still have the O2 sensor wiring to repair, so not like I didn't already have wiring to fix.

The new main seal seems to work. My dad will be driving the car this week. I didn't bring it back to NoVA as the temp was in the teens last night and breaking down on a country road on my way from my dad's back to NoVA would have REALLY SUCKED. I'd rather put a few more miles on the car to be sure everything's reliable before I bring it back to my place.

I was very please to find that the radiator can be R&R'd *WITHOUT* removing the fan.


New tensioner vs. old:



Naked M20 timing drive:



Banged up A/C condenser, courtesy previous maintainer



Repaired as best I can via a fin comb:



A fin comb for anyone not familiar:



Almost done:

[Aaron]

That sounds like a real pain in the ass. I hate working on cars where it seems everything goes wrong, one of my 3.4s was like that in high school. Since then I've got even more of an appreciation for new cars/engines/parts. You're doing a thorough job though.

[The Dark Side of Will]

Most of the goofiness in this car is because a hack worked on it previously... after all, threads don't come out like a coil spring unless they have been grossly over torqued. Most of the problems just look like things some incompetent jackass would do with cutters and duct tape after watching The Fast and The Furious.

And thanks... being thorough now saves me ass-pain later.

[The Dark Side of Will]

OMFG, it keeps getting better.

After the car started fine for me, I left to go back to Northern VA. I expected my dad to drive it over the next week+ to figure out what the kinks were.
It wouldn't start for him. At all.

We troubleshot it today and found that the injectors are not getting +12V. WTF?

Look in the electrical manual and find that the injectors get unfused power from the main relay. There's lots of buzzing and clicking in the engine bay when I turn the key on, so I know the main relay works.

I noticed in the wiring diagrams that the injector wiring goes through C191. I followed the injector harness wiring and found an ominous looking ball of electrical tape in the middle of the harness before it joined the main engine harness. I looked at my dad's two E30's and found the 7 pin round connector that the manual calls out in that location. Uh oh.

I unwrapped the ball of electrical tape and found that all 7 wires had been "spliced" with 10 or 12 gauge brown hookup wire. The inidividual "splices" are wrapped with more electrical tape, so I don't know yet if they are twisted or soldered. I just finished putting together a list of the color codes and wire sizes for each circuit going through the connector... I guess I'll splice in the hook up wire I have that's closest to the stock color until I can either get a new BMW connector or a combination of weather packs to replace the original C191.

Is there anything on this car this guy hasn't hacked up? Is there anything he's touched he hasn't mangled?

Code: Select all

Pages in E30 1988 electrical manual

132 (connector face)
39 (Pins 1,2)
62 (Pins 3,4)
38 (Pins 5,6,7)

Pins:

Pin	Engine		Injector	Notes
1	0.5 BR/RD 	0.5 BR/RD	CTS input to DME
2	0.5 BR/OR	0.5 BR		CTS ground
3	0.5 BR		0.5 BR		Temp Sender Ground
4	0.5 BR/VI	0.5 BR/VI	Temp Sender to Gauge
5	2.5 RT/WS	2.5 RT/WS	Injector +12V supply
6	0.5 BR/WT	1.5 BR/WT	Injector 1,3,5 signal
7	0.5 BR/YL	1.5 BR/YL	Injector 2,4,6 signal

[Emc209i]

Sucks. I suppose the bright side is that there is only so much to replace before you've rebuilt the entire car.

[Emc209i]

How about some pictures of the car?

[CincinnatiFiero]

Why not say forget the wiring, and worry about wiring in the S62!?

[The Dark Side of Will]

Because I want to drive the car...

When I get the Jeep 4.0 off my engine stand (soon) I'll get the S62 on the engine stand. First order of business is to get the crossmember mocked up to the engine and figure out if I have to make my own mount arms or mount towers and take very careful measurements to be sure it will fit in the E30 engine bay.

Wiring before repair:



After (Note that I had not shrunk the shrink tube at this point):



The dregs that I removed:

[Aaron]

I'm sure it was, but was that your problem? That's so gross, it's amazing the things PO's do to cars. I don't think I've ever seen a repair, aside from a simple filter replacement, by a PO that meets the lowest standards.

[The Dark Side of Will]

As you can see above, the ends of the wires were heavily corroded. The splices were not well encapsulated. Even though they were soldered, a few came apart in my hands as I was moving the wires so that I could cut them off.

The injectors were not getting +12V due to deterioration of one of the splices on the 12 ga RD/WT wire.