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irish44j (Forum Supporter)
irish44j (Forum Supporter) MegaDork
12/28/21 7:10 p.m.

The radiator should have lower mounts that look like this.. 

Although thinking back maybe the M42 radiator has the mounts on the sides now that I think of it. So you may want to check and see if that is the case. I've had so many engines in mind I forgot what mounts go to which engine lol

Berck
Berck New Reader
12/28/21 8:29 p.m.

In reply to irish44j (Forum Supporter) :

They might not fall out, as they'd have to bounce up to come out since the bump stop will hold them in like this, but it wouldn't take much of a bounce.  I put it on the ground with one of the hotbits springs with a rubber pad, and one of the red springs.  The red spring without the pad sits 1/4" higher.  Jumping on the springs reveals that the red one has only a very slightly lower spring rate.  I'm thinking the red ones with the pads are probably the way to go.

I'm a bit confused about spring rates on this car.  I'd have guessed that rally cars would run significantly lower spring rates than a track car.  The spring rates here seem like a lot even for a track car.  I stood on one of the front shock mounts and got as close to I could as jumping.  I'm 225 lbs, and it didn't seem like I could compress the springs by more than 1/4".  I can pull them out and measure them, but it doesn't seem like it's even in the right ballpark.

Berck
Berck New Reader
12/28/21 9:02 p.m.
irish44j (Forum Supporter) said:

That is standard operating procedure for M42 even after rebuilding and resealing. I think some of the leaking comes from the timing chain tensioner which is that little plug-shaped thing on the side. I also used to get a lot of leaks from the sensor that plugs in right above the water outlet near the top of the front. 

Really?  Yikes.  Fine German engineering!  Well, at least there's a hole at the top to add more oil.  I ordered a valve cover gasket, so I guess I'll do that and then ignore the rest.

 

irish44j (Forum Supporter)
irish44j (Forum Supporter) MegaDork
12/28/21 9:30 p.m.
Berck said:

In reply to irish44j (Forum Supporter) :

They might not fall out, as they'd have to bounce up to come out since the bump stop will hold them in like this, but it wouldn't take much of a bounce.  I put it on the ground with one of the hotbits springs with a rubber pad, and one of the red springs.  The red spring without the pad sits 1/4" higher.  Jumping on the springs reveals that the red one has only a very slightly lower spring rate.  I'm thinking the red ones with the pads are probably the way to go.

I'm a bit confused about spring rates on this car.  I'd have guessed that rally cars would run significantly lower spring rates than a track car.  The spring rates here seem like a lot even for a track car.  I stood on one of the front shock mounts and got as close to I could as jumping.  I'm 225 lbs, and it didn't seem like I could compress the springs by more than 1/4".  I can pull them out and measure them, but it doesn't seem like it's even in the right ballpark.

I run 250# linear 10" springs up front, and e36 M3 OEM springs in the rear, which are the equivalent of about 200-220# progressive at the wheel (actual rate is different since they're not mounted at the apex of the hub). I've found these rates to be about  right for a stage car with all the gear. Other guys are running similar rates.  

irish44j (Forum Supporter)
irish44j (Forum Supporter) MegaDork
12/28/21 9:33 p.m.
Berck said:
irish44j (Forum Supporter) said:

That is standard operating procedure for M42 even after rebuilding and resealing. I think some of the leaking comes from the timing chain tensioner which is that little plug-shaped thing on the side. I also used to get a lot of leaks from the sensor that plugs in right above the water outlet near the top of the front. 

Really?  Yikes.  Fine German engineering!  Well, at least there's a hole at the top to add more oil.  I ordered a valve cover gasket, so I guess I'll do that and then ignore the rest.

 

I've never noticed with the M42 (or the M50, which leaks in the same place) any real significant oil loss (at the dipstick), honestly. It gets gunky there over time for sure but I also don't really clean it much lol. I never had to "add oil" to any notable degree in 5-6 years of running the M42. For a competition car, no biggie anyhow. Your crew should check oil at service, and you'll check between events. not like you're gonna be putting 20k miles a year on it lol.

incidentally, the M42 sitting in my garage is oily and gunky as hell :) So I feel your pain. 

And yeah, it could just be the VC gasket as well. 

 

Berck
Berck New Reader
12/28/21 11:50 p.m.

With the GRM filter, that could be e36 m3 OEM springs, or E36 M3 OEM springs...

irish44j (Forum Supporter)
irish44j (Forum Supporter) MegaDork
12/29/21 10:06 a.m.
Berck said:

With the GRM filter, that could be e36 m3 OEM springs, or E36 M3 OEM springs...

Lol. I meant the actual car. E 36 m3

iansane
iansane HalfDork
12/29/21 10:23 a.m.

I wouldn't bother with the valve cover gasket unless it's leaking other places too. It's probably not leaking at the v/c junction but where the head meets the timing cover. The thin metal gasket always leaks and the only "fix" is doing a headgasket and resealing that. You could try sliding the timing cover out the bottom from underneath the head but that's a lot of work as an attempt. My girlfriends truck has been leaking there for 5 or 6 years and it's just cruddy. Swap the timing chain tensioner (or just crush washer if you're cheap) and sensor oring and that'll probably take care of the big leaks.

 

The rad mounts are halfway up the rad on the later cars like this m42. You can see one of the metal tabs sticking off the frame in the back of your picture. Should be another one on the driver side. Unless this wasn't originally an m42 car?

Berck
Berck New Reader
12/29/21 10:39 a.m.

It's a 1991 318is, which appears to be originally an M42.  I'm not seeing the tabs?  If you guys can point me to what I need to buy to properly mount the radiator, I'd be grateful.  On the other hand, the zip ties are surprisingly sturdy and it's probably been this way for awhile.

iansane
iansane HalfDork
12/29/21 10:52 a.m.

Definitely an original m42 car then.

Check this link for OE part numbers you can then google for suppliers. (Amazon actually has a lot it)

https://www.realoem.com/bmw/enUS/showparts?id=AF93-USA-11-1990-E30-BMW-318is&diagId=17_0003

 

It looks like that's the metal tab (circled in blue) that the mounts sit on. There are plastic pieces (#3,4) from the realoem link that clip in and then some rubber bushings. (#5). 

Berck
Berck New Reader
12/29/21 12:37 p.m.

Thanks!  It's not clear to me how it all goes together from those diagrams, but I'm guessing I can figure it out when I've got the parts in hand.

Berck
Berck New Reader
12/29/21 1:18 p.m.

Also looks like there's a tab in the location of Josh's photo (has a white zip tie through it), but not the metal bump to support the rubber ring.  

I ordered all the bits to mount the radiator.  And new hoses, thermostat and water pump while I'm at it.  And another radiator.  Probably overkill, but I have no idea how old some of this stuff is.  It's not any newer than 5 years old, and it might be 31 years old.

Berck
Berck New Reader
12/29/21 7:59 p.m.

I still haven't actually fixed anything, but at least I've made something less dirty.  I need to reposition the driver's seat, so when I removed it I went ahead and removed the belts and the diamond plate so that I could properly clean underneath it all and get a look at any rust.

After an hour or so with a bucket and sponge:

The line leading to the gas pedal is pretty rusty.  I can't poke through it yet, but it's a matter of time.

I went ahead and sprayed some fresh paint and I'll put it back together tomorrow. 

As far as I can tell, ARA doesn't seem to care about dates on the seats?  They are FIA seats, but were manufactured 20 years ago.  The belts, shockingly, are good through 2022.  They were new in 2017 and have all of a single event on them.

irish44j (Forum Supporter)
irish44j (Forum Supporter) MegaDork
12/29/21 9:01 p.m.
Berck said:

Also looks like there's a tab in the location of Josh's photo (has a white zip tie through it), but not the metal bump to support the rubber ring.  

I ordered all the bits to mount the radiator.  And new hoses, thermostat and water pump while I'm at it.  And another radiator.  Probably overkill, but I have no idea how old some of this stuff is.  It's not any newer than 5 years old, and it might be 31 years old.

I can see both lower mount brackets in your picture. They're just missing the cylindrical rubber pieces that sit on them. 

irish44j (Forum Supporter)
irish44j (Forum Supporter) MegaDork
12/29/21 9:04 p.m.
Berck said:

I still haven't actually fixed anything, but at least I've made something less dirty.  I need to reposition the driver's seat, so when I removed it I went ahead and removed the belts and the diamond plate so that I could properly clean underneath it all and get a look at any rust.

 

After an hour or so with a bucket and sponge:

 

The line leading to the gas pedal is pretty rusty.  I can't poke through it yet, but it's a matter of time.

I went ahead and sprayed some fresh paint and I'll put it back together tomorrow. 

 

As far as I can tell, ARA doesn't seem to care about dates on the seats?  They are FIA seats, but were manufactured 20 years ago.  The belts, shockingly, are good through 2022.  They were new in 2017 and have all of a single event on them.

The line of rust heading to the pedal is along the edge of the much thicker center chassis rail (where the transmission rear mounts are, among other things). But the rust is usually just outside the thicker metal area where it's just thing sheet metal.

Correct, ARA (and NASA, and USRF IIRC) do not have an expiration on seats, as long as they have the correct FIA certification and are have no visible cracking or damage. The Sparcos I just replaced were from like 2006 or something. However, belts do expire. Make sure you buy FIA stuff (with 5-year expiration) and NOT SFI stuff (with 2-year expiration). That includes HANS, btw. 

Berck
Berck New Reader
1/3/22 10:31 p.m.

I have a kill switch!

I'll cover the hole from the old non-connected kill switch with the required decal.

 

Far better than splicing and adding a bunch of 0AWG behind the panel.

I also found the problem with the fuel pump wiring.  The yellow one wasn't working, but after I found the break, I went ahead and cut the orange one for the other fuel pump, and I'm glad I did.

Not really sure what it was rubbing on, it's at the aft end of the door sill, presumably the same route it took when it was stock, as it runs with the big battery cable.  They were sleeved, and it wore through the sleeving too.  So now it runs in front of the cage.  I hope I don't have to worry about the battery wires back there.

Found some trunk rust and spent some time with a wire wheel.  I'll hit it with some phosphoric acid and paint...

I was stuck waiting for parts; now I have lots of parts but have to go back to work :(.

Berck
Berck New Reader
1/8/22 11:20 a.m.

ARGH.  I spent some time reading the ARA rules and found this,

"All the fuel pumps must only operate when the engine is running, except during the starting process."

So... I need to put the oil pressure relay thing back in.  Probably other ways to accomplish this, but it's as good as any.  It's a reasonable requirement, but I'm not sure it's one OEMs tend to meet?  I'm pretty sure in most modern cars, if they stall, the fuel pump is going to run.

Other rules that I'm currently in violation of: "Unless a car was manufactured before a catalytic converter was required in the U.S.A., then a functioning catalytic converter must be retained or installed."  There's no catalytic converter installed.  And I don't weld.  Sigh.

Also: "All reversing lights may only switch on by engaging reverse gear."  For reasons I do not understand, my reverse lights are wired to a toggle switch.  I wonder if that rule is worded how they actually mean it--it sounds like I could also meet the letter of the rule by simply disabling the reverse lights.

irish44j (Forum Supporter)
irish44j (Forum Supporter) MegaDork
1/8/22 5:17 p.m.

On an E30 the fuel pump only runs when the engine is running. The fuel pump relay OEM is controlled by the crank sensor as I recall. So unless the engine is spinning the fuel pump relay does not activate. In short, engine kill switch also kills the fuel pump relay. Or at least with stock wiring it does.

Berck
Berck New Reader
1/8/22 7:55 p.m.

Interesting. So you don't get fuel pressure until you crank the starter?  With two very much non-stock fuel pumps with non-stock wiring, I don't get that benefit.  I guess I could try to find that wiring, but putting back the relay that was there will do the same thing.

I somehow spent all day in the garage with not much to show for it, but this:

So now I can have an oil pressure gauge without piping oil into the cabin, just electrons. Haven't managed to wire the gauge yet--that's the wire for the fuel pump relays and warning light.

I did spend some time grinding on trunk rust.  I stripped down the rusty strut tower brace and repainted it.  This is stuff that I should probably skip, given that it's not going to make the car more reliable in the short term and the car lives in Colorado now...  The whole state is a sort of rust-delaying time warp.

irish44j (Forum Supporter)
irish44j (Forum Supporter) MegaDork
1/8/22 8:22 p.m.
Berck said:

Interesting. So you don't get fuel pressure until you crank the starter?  With two very much non-stock fuel pumps with non-stock wiring, I don't get that benefit.  I guess I could try to find that wiring, but putting back the relay that was there will do the same thing.

That's my recollection. I think it may do a quick prime of the HP pump when you turn the ignition to accessory, but I may be thinking of my Porsche. But I'm pretty sure that when diagnosing a fuel issue years ago my research turned up that the relay doesn't get power from the DME until the DME detects the engine is cranking via the crank position sensor. IDK, maybe your previous owner decided he wanted to be able to prime it or something?  In any case, I'm quite sure my fuel pump doesn't do anything in the accessory position with the engine not spinning. The signal for the fuel pump relay comes directly from the DME, not the ignition switch. 

Berck
Berck New Reader
1/9/22 9:12 p.m.

Accomplished some things.  I turned this:

Into this:

I'm guessing that the car must have been stored outdoors for that 5 years.  I drove it 20 miles or so and the rear brakes *still* looked like that.  Also caught on fire.  But that's some seriously rusted rotors.

I just replaced calipers, rotors & pads all the way around.  The front calipers were probably okay, the rears were probably rebuildable.  But the car sat for 5 years in New Hampshire, reman calipers are cheap, and I'd rather just not worry about it.  Of course, I've had terrible luck with reman calipers on Miatas, so I'm hoping the BMW situation is better.

I found a parking brake mechanism on one side.  Sort of surprising, so here's a rusty pile of freshly-removed unsprung weight:

Super-significant, I'm sure, given the ~100lbs/each that rally tire/wheel combos seem to weight.

I'm not sure if this is the right thing to do or not, but with some fresh rear spring pads of the 15mm variety, and wedging the old rear pads into the top, maybe I'll get somewhere near a rally ride height with my tallest springs:

 

Oh, also discovered that someone thought a zip tie was a good idea for CV boot attachment.  It's not:

So I get to replace that for a stupid reason.  I'm wondering how hard removing the half shafts is going to be.

adam525i
adam525i Dork
1/9/22 10:28 p.m.

Half shafts are pretty easy to pull and then pop apart to change out the boots so worth doing.

Check to see if those caliper are coated in anything or just sandblasted bare. If they are bare it's worth putting some paint on now before they turn rust orange, black rustoleum bbq paint brushed on has held up well for me on the track car.

iansane
iansane HalfDork
1/10/22 10:05 a.m.

I chased that fuel pump thing for a long time on my m42 swapped car. I'm pretty sure it does a 2 second hit to re pressurize the system but normally gets triggered from seeing engine RPM. And with an older pump, that quick prime isn't enough to get the whole system vacant of air so starting can be next to impossible. (even clutch starting down a steep driveway. Leaving your car stranded in the middle of a cul de sac. That's never happened to me or anything...)

irish44j (Forum Supporter)
irish44j (Forum Supporter) MegaDork
1/10/22 6:50 p.m.

I hope you are planning to do some kind of locking hydro brake parking brake (or does it already have something like that?) There are a lot of times you will be sitting in a line on a steep hill and you really need to get out and pee. And your co-driver will get annoyed with you if you have to shut down the car and his electronics in order to do so without the car rolling away lol

Berck
Berck New Reader
1/10/22 8:00 p.m.

Argh--It never occurred to me that reman calipers *weren't* painted.  I'll try to investigate.  But you're right, if they're not, painting them now would be probably be worth a $6 can of paint.

I definitely won't have trouble priming the fuel system:)  I'll have the start-bypass switch so it'll let me run both fuel pumps without oil pressure for starts, then I can flip the switch to make it so that a dead engine results in dead fuel pumps.  Which, when I think about it, is a sane idea even if the rules didn't require it.

I do, in fact, have a locking hydro parking brake, but I wanted to ask you guys about it.  I have this:

This works great as a parking brake.  It seems less than ideal for on-stage use, however, since you've got to push the button.  And the button is somewhat recessed, which seems very not-ideal.  I was considering a few options:

(1) Remove the ratchet mechanism and add a hydraulic parking brake.  In airplanes we use a one-way valve thing where when engaged, you put pressure in the system and it stays there until you disengage.  I'd assume there's a similar thing available for cars--I could certainly use the one I'm putting in my airplane but it's expensive, and also airplanes have totally separate left/right brakes, so it's actually two valves and I only need one.

(2) Remove the ratchet system and carry some sort of wedge to shove under the parking brake.

(3) Find some way to enable/disable the ratchet mechanism.

(4) Extend/replace the button so it's easier to push

(5) Leave it as-is. It's a rear-wheel drive car and I'm no Colin McRae; do I really need a handbrake?  As much as I enjoy unnecessary handbrake turns on the street in the snow, it's maybe just asking for trouble?  On the other hand, why did I buy a rally car if I can't do handbrake turns?  And if it's there, I'm likely to use it and then get it stuck like an idiot.

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