Elektrik: Mess- und Einstellwerte Zündanlage M70

[Erich]

Ich hab mal letztes Jahr auf BB zusammengefasst, was ich selber getestet hab an meinem + an einem E31 getestet und auch was andere geschrieben haben, auch unterschiedlich M1.2 und M1.7, am E31 mit 1.7 war nur das Zuendkabel nicht richtig drauf auf Kerze 12 und es gab Probleme.:


Subject: it might start, but will go out immy Posted on: 2013-11-17

at least that was the result of our problem solving yesterday on a E31 850 with M1.7 352 Motronic, M1.2 might be different.
The problem:
engine always started for some seconds and then stopped. After checking a lot of things for the 'usual' faults, testing fuel pumps, distributors and rotors, removing fuel pumps + testing them (before we tested each fuel pump separately by giving power to the fuses with ignition off), even replacing one, testing fuel pressure etc., we found out that the ignition wire for plug no. 12 was not properly installed/attached, plugged that in and the engine was starting and did not stop. So the donut of #12 did not get any signal because the spark plug #12 did not spark.Also for me a new experience. Always something new to find on these cars '-)

comment by Johan: "AFAIK the 6 and 12 are used as an indication to sequence the injectors i.e. fire them in groups of 3. If the connection to the sensor is not there or the plug isn't firing the engine should still start, but the 1-6 and 7-12 open simultaneously instead of in groups of 3."

That is what I believed also till yesterday.

Other old - partly confusing- info collected from the net:

Just read a post from RF E31 by a rather experienced forum member Mark in SBA . He showed a service diagram for DME 1.7 indicating that:
"If plug lead 6 or 12 (the ones with the inductive pickup donuts on them) are disconnected or short, a protection circuit embedded within the Motronic will severely clip the duty cycle of the injectors for that side to protect the catalysts from being drenched in raw, unburned fuel."

Called the "Catalytic converter protection function", I wonder if my DME 1.2 may not have that function, thus I was able to pull off one or both Cam-Position-sensor plugs and the M70 can still be started. That may explain the contradicting observations. Anyone with Motronics 1.2 like to try an experiment (by pulling off a Cam-position sensor plug from front center of engine and see if engine can start?)
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Subject: results of test (simple)
Author: hairwithit Posted on: 2009-05-16

Shogun's 1988/89 750iL
well we disconnected the passenger side cylinder ID plug at front of engine.
key to position 2, EML light comes on, after a few seconds off.
engine start, runs on only 6 cylinders and rough -- NO EML or other warning!
Accelerator used, still no warning.
Reconnected and restart -- all 12 running, no warning.

Disconnected both cylinder ID plugs.
same result -- engine runs but only 6.

Used Peake and found no fault codes related to engine --ummm

Reconnected and runs like a champ. Still no warnings.
I thought the engine would stop with both disconnected but no true.
Over to you guys
----------------------

Tim Meek, U.K. board, Author: shogun : 2009-05-16......
comments on this as following: "The sensors on ignition leads 6 and 12 are not there to disrupt the injector duration, they are there to identify the camshaft position and are a direct forerunner of the camshaft sensor. The sensors are called 'cylinder identification sensors' and detect when cylinders 6 or 12 fire, they do not measure the primary circuit, how could they, they are stuck on the ignition leads! This is not part of the EML system, any failure will not light the EML indicator. It is a basic ECU input that is found on straight-6's that do not have EML as well as EML variants of both the M30 and M70.

Without the cylinder identification sensors, the ECU's do not know which of the two unique revolutions the crankshaft is on. This does not matter to the ignition as the spark is directed to the correct cylinder by the distributor. It does matter to the injection circuits which should fire every two crankshaft revolutions or every one camshaft revolution.

During cranking the only reference signal is the crankshaft sensor and 'double injection' is maintained until the ignition from cylinders 6 and 12 are detected. From this point on the ECU is aware of the correct camshaft position and can fire the injectors every two crankshaft revolutions. If the cylinder identification sensors fail to detect ignition pulses then the injectors continue to fire every crankshaft revolution but the injector duration is reduced to prevent damage to the catalytic converters."
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Subject: O2 Sensor Termal Shock recall...M70 engines
Posted on: 2009-08-26

I just got on my computer an updated copy of the TIS BMW software,in the engine alert for M70 engines there's one called "O2 Sensor termal shock" named:SI 110896164 released by BMW AG in 01/1997.

Symptom: Irregular idle and shaking when driving.

Cause: stop and go driving and short distances will cause water residues on the cat,a cold start can cause the failure of the O2 sensors caused the termal shock

Solution: O2 Sensor delayed heating with a relais...

Parts:
O2 Sensor 11781733628
Delayed heating relais 11781745829
Cables kit 12511745758
---------------------------------

here explained for Motronik 1.7 page 19
Catalytic converter protection
 http://www.e32-schrauber.de/bmw/date...me-1_7-eml.pdf
------------------------
catalytic converter protection
 Catalytic Converter Protection M70 Photo by shogun_bucket | Photobucket

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comment on the German e31 forum from someone:
with the 1.7 it is the same as with 1.2:
no big change when removing the cylinder identification plug, engine runs a bit more rough but still contnues to run according to my test.
---------------------
So I am really confused now what works or not.

[fuffi_lwl]

Aha.
Also meiner ist Nummer -352, also die neuere Motronik. Mit beiden Donuts abgeklemmt geht er aus. Starten lässt er sich wie gesagt nicht mehr danach. Geht nach kurzem Lauf einfach aus. Also ist das alles normal und ich muss mir keine Sorgen machen?

[Erich]

Das sollte mit der M1.7 352 korrekt sein, hat ja diese Funktion
Kat Protect
 Catalytic Converter Protection M70 Photo by shogun_bucket | Photobucket

[Erich]

Gestern haben wir kleine Aenderungen an einem M70 B12 mit Motronik 1.7 -352 vorgenommen.
Die Kettenraeder 11311718673 Steuertrieb-Steuerkette haben Laengsloecher
 RealOEM.com BMW E32 750iL Timing and valve train-timing chain
Gefunden haben wir diese Bilder, wo dargestellt wird, dass durch Laengung der Steuerketten sich die Ventiloeffnungs/-schliesswinkel aendern koennen. Ist relativ leicht zu korrigieren, wir haben 1 1/2 Tage gebraucht, weil ja oben alles ab muss. Und wir wollten uns Zeit lassen.
Text von 8Tech, Bilder sind von einem S70 Motor, Prozedur ist gleich:

HowTo-> Engine: Reset V12 Valve Timing.
Correct valve timing, or cam timing as some know it is very important for the smooth running of an engine and to extract the optimum performance from the engine. Just as ignition timing is set to produce the spark at the correct time, valve timing sets the valves to open and close at the correct time, both in relation to the crankshaft position.

This has become more and more important in recent years where extracting the very best efficiency from an engine has meant special timing tools for locking the engines on almost all new cars, whereas 20 years ago you set cambelt timing to the nearest tooth on the pulley/sprocket and only modified engines had adjustable aftermarket vernier pulleys to optimise the timing.

In the early 1980’s, the hot mod was to slot the cam pulleys to allow us to optimise our timing on our drag bikes and guess what the E31 V12 has? Yep, slotted sprockets.

 http://i283.photobucket.com/albums/k...w/IMG_0050.jpg
As you probably know, the crankshaft is connected to the cams through a chain and during 2 revolutions of the crank, each cam rotates once, at exactly the correct time, well almost. Assuming that the timing is exactly set correctly when the engine is assembled at the factory, as the chain stretches, the distance between the crank teeth and the cam sprocket teeth increases and this causes the valves to open and close too late due to a retarded camshaft.

Luckily, with slotted sprockets on the cams, we can rotate the cams on their sprockets to advance them back again to the correct position. To find this correct position for the cams, there is a pair of flats on each cam that is used with the appropriate cam locking tools, part nos C022 x 2 of
 http://i283.photobucket.com/albums/k...IMG_0049-1.jpg
to set them in the correct position when the crank is at Top Dead Center (TDC).

You can find TDC either with the crank locking pin inserted between the back of the block and the flywheel, or as I did, by using the TDC mark on the front pulley. Using my method, you do not need to remove the timing chain tensioner to take up the chain slack.

 http://i283.photobucket.com/albums/k...w/IMG_0041.jpg
Firstly, rotate the engine slowly using a 27mm socket on the front pulley bolt, in a clockwise (normal direction of rotation) direction.
 http://i283.photobucket.com/albums/k...w/IMG_0044.jpg
This will cause the crank to pull the cams around taking up any chain slack. Continue until the TDC mark on the pulley approaches the timing mark on the front cover, and very slowly as you approach the marks aligning.

Stop when they are aligned. If you go too far, DO NOT GO BACKWARDS to align the marks, go around another complete crank revolution. If you went backwards, the tension on the chain will be on the wrong side and the timing will be miles out.

With the crank now at TDC, slide the timing tools on the cams and see if they sit flush with the head face. If not, as seen here, the timing needs to be reset.
 http://i283.photobucket.com/albums/k...w/IMG_0042.jpg
 http://i283.photobucket.com/albums/k...w/IMG_0043.jpg
There are 6 x 10mm bolts holding each cam to its sprocket, and with the engine set as it is you can slacken off the top 3 on each cam.
 http://i283.photobucket.com/albums/k...w/IMG_0045.jpg
Now remove the timing tools and rotate the crank clockwise 1 revolution again and as before, bring the timing mark on the crank pulley to approach the timing mark on the front cover. Now refit the timing tool on the cam of cylinders 7-12 as shown. SLOWLY rotate the crank until the tool sits correctly on the head.

 http://i283.photobucket.com/albums/k...w/IMG_0040.jpg
Now slacken the top 3 bolts on the cylinder 7-12 cam so that all 6 are now loose on that cam.

SLOWLY rotate the crank BACKWARDS (anti-clockwise), watching the sprocket rotate on the locked cam until the bolts are almost at the ends of their slots. Look at the timing marks on the crank pulley and front cover and you should be to the left of the cover mark with the pulley mark.

 http://i283.photobucket.com/albums/k...IMG_0047-1.jpg
Now slowly rotate the crank as before (clockwise) until the timing marks align. With the timing marks aligned and the tool still locking the cam in position, tighten the top 3 sprocket bolts on that cam.

You can now remove the timing tool and repeat the procedure for the cyl 1-6 cam, exactly as before, locking up the top 3 sprocket bolts again
 http://i283.photobucket.com/albums/k...IMG_0046-1.jpg
Now, with the cams correctly timed, rotate the crank 1 full revolution which will expose the remaining 3 loose bolts on each sprocket which can now be tightened.

You can finally rotate the crank once more and setting the timing marks up correctly, you should be able to fit the cam timing locking plates flush with the head. If so, then your cam timing is now correct.

 http://i283.photobucket.com/albums/k...IMG_0037-1.jpg
There are a few assumptions made in this procedure and that is that the flats on the camshafts and the position of the TDC mark is accurate. For almost all cases, these are perfectly adequate for the purposes of setting cam timing but for the true perfectionist, a degree wheel would be used on the front pulley with a micrometer dial gauge used to find true TDC, and the valves would be set using a dial gauge on the cam lobes to accurately set the cam position.

NOTE: All pics taken with cam oil spray bars removed for clarity. 8Tech.
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Und so aehnlich wi in seinem Bild war auch am B12 die Zeit nicht mehr richtig gestellt, war ein Spalt beim Messen aehnlich wie hier, rechts sieht man es

[--750il--]

hab ich doch weiter vorne schon darauf hingewiesen dass nur noch die steuerkette bleibt...

wo bekommt man denn das werkzeug her?

[Erich]

Ja, ich weis, nur haben wir es jetzt gemacht und ich hab auch Bilder. Suche im net nach: BMW Nockenwellen Arretierung M40 M43 M70 M73 Werkzeug
BMW original Nummern: Nockenwellen Blockierung 11 3 190, Absteckdorn für das Schwungrad 11 2 300
Für den M70/M73 benötigt man 2x die Nockenwellen Blockierung

Gibt es zum Beispiel hier:

 BMW Nockenwellen Arretierung M40 M43 M70 M73 Werkzeug - KFZ Spezialwerkzeug und Autoteile im XXL-Automotive Onlineshop

Ich hab mir vor Jahren mal welche machen lassen
 http://www.7-forum.com/forum/24/nock...ug-105554.html
Abmessungen auf meiner Seite unter Upgrades/Fun - Tools
 Shogun's Repair Guides for BMW Seven Series

Wir haben das gestern mal ausprobiert und Vergleichsweise ein gekauftes Werkzeug dazu gehabt. Haben festgestellt, dass mein Werkzeug mit der Oeffnung von 42mm minimal zuviel Spiel hat, das andere hatte gemessene 41.6mm. Das sitzt dann richtig stramm drauf auf der Nockenwelle, aber vielleicht war die ja auch schon eingelaufen und meins hat die genaue Abmessung
Kann ja mal jemand nachmessen.

Gibt es auch massig im internet zu kaufen.

[fuffi_lwl]

Tja, in die Richtung tendiere ich ja auch, um ehrlich zu sein. Nur leider wird die ganze Sache irgendwie nicht so recht günstig zu beheben sein. Sieht bei Erich nach einer Menge Arbeit aus.

[17er Schlüssel]

Habe jetzt nicht alles mit verfolgt,aber wenn sich die Kette längt,sollte man nicht nur die Steuerzeiten über die Langlöcher korrigieren,sondern besser gleich den GESAMMTEN Steuertrieb ersetzen.
Und wer den M70 kennt,weiß das wenn sich die Kette mal gelängt hat,und die Schienen eingelaufen sind,es dabei meist nicht bleibt.
Die Korrektur der Steuerzeiten bleibt so nicht all zu lange erhalten.
Schaftdichtungen,Auslaßführungen,Schlepphebel sowie Hydros sind dann meist auch fällig,welche nicht unerheblich für den ruhigen und leistungsstarken Lauf ausschlaggebend sind.
Des weiteren sollten die Ventile und deren Sitze überarbeitet werden da bei der Laufleistung diese oft verkokt/verschmutzt sind,sowie sämtliche Dichtungen am Motor (da ausgehärtet) getauscht werden.
Habe mittlerweile schon drei M70 überholt,darunter einen B12.
Sie zeigten alle sammt immer das gleiche Verschleißbild zwischen 180 und 220 TKM.
Wenn die Steuerzeiten neu eingestellt werden,sollte dies min. zwei mal nachgeprüft werden.
Das heißt Steuerzeiten einstellen,Motor min. 3x von Hand durchdrehen,Steuerzeiten überprüfen.
Gleiche Prozedur nochmal durchlaufen.
Die Kettentrieb setzt sich noch nach,deshalb ist die Überprüfung zwingend notwendig.Sonst kann wie die Bilder zeigen,eines der Werkzeuge leicht von der Planfläche abheben,was bei Nichtbeachtung später Unruhe bringen wird.
Auch wichtig wie schon erwähnt,die Absteckwerkzeuge sollten absolut maßhaltig,und nicht "ausgelutscht" sein.
Also schön straff ohne Spiel auf die Absteckposition der Nocken gehen.
Sonst bringt das ganze Einstellen nichts.
Alex

[dansker]

Habe an meinem M70 seinerzeit beiden Nockenwellen, Schlepphebel und Hydros Gewechselt, und dann die Steuerzeiten neu Einstellen müssen!.Eigentlich sollte es ja Selbstverständlich sein, das man nach der Einstellung, die Kurbelwelle um einige Umdrehungen weiter Dreht, und dann die Steurzeiten nochmals prüft! Habe mir damals extra bei meinem Nachbar, der eine CNC-Dreherei hat, 2 Satz Blockierwerkzeuge für die Nockenwellen Anfertigen lassen, und habe einen Satz Übrig!

Gruss dansker

[17er Schlüssel]

Sollte...ja!
Wenn man aber hier im Forum so mit liest,dann fällt schnell auf
das sich auch immer mehr "unwissende" an den e32 Triebwerken versuchen.
Gruß
Alex