Bericht: Motoruberhohlung E28S M5

The next step on my ‘to-do’ list is the reconnection of the shifter mechanism. Two weeks ago, we analyzed that the gearbox rod joint caused some play in the movement of the shifter-rod in the longitude direction (yellow arrow). The play in vertical direction (purple arrow) is negligible.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img530.jpg]

Despite that the cost of this part is far from excessive, it also is not negligible so after some deliberation, I bought a new one. A comparison between both old-and new parts revealed that the hole is eccentric, i.e. the longitude play is normal. A visual comparison did not result in any differences, but for 22 Euro, I could not bother. Note the two O-rings that cannot be seen, but are not supplied with the rod-joint.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img531.jpg]

The other (lower) purple arrow shows a completely deteriorated plastic washer that fills the gap between the gearbox-rod joint and the gearbox shifting-shaft. Even though the connecting rod itself fixes the gearbox rod joint to some extent, the eccentric hole allows the rod itself some movement and without a functional washer also a slight additional movement around the vertical axis. This plastic washer prevents additional transversal load to the shift-rod seal in the gearbox. These are known to leak, even after replacement, but I sincerely doubt many workshops are aware of the plastic washer in the gearbox-rod joint. Always replace this part whilst you’re at it.

The gearbox rod-joint and the plastic washer are not the only parts in the system that need to be checked. This also applies for the bushings in the shifter arm on the gearbox. Especially on cars that have seen ‘appropriate use’ these rubber bushes can cause sloppy and inaccurate shifting-feel. The bush itself doesn’t cost much, but is very difficult to reach with the gearbox in place.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img532.jpg]

Measurements learned that the play in #231’s old bushes is about ±2mm. Since I have the entire shifting linkage out of the car, replacing the bush was easy. I cleaned the arm, added a tiny amount of lubricant and pushed the new bush in place.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img533.jpg]

The fixing clip is the reason why it is close to impossible to replace this bushing with the gearbox in place. It is located at the top of the gearbox, i.e. no working space to apply enough force to lift the clip from the alloy housing.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img534.jpg]

The following picture shows the shifter arm with the new shifter (shorter model) before these are installed.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img535.jpg]

As the bushes are the parts that wear out, the shifter-arm and the shifter-rod can be reused. Last but not least, I finished the shift-linkage with a new boot (the old one was cracked).

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img536.jpg]

Even though I cannot give driving impressions, the first tests (dry shifting) revealed a much tighter and more precise gear-change.

Work is slowly but steadily progressing. Yesterday evening, I finished the installation of the propeller-shaft to the gearbox. The hardy disk and the three M12 bolts were replaced in April 2008. As these have been used no more then 500km, I reused the hardy-disk and the bolts. The self-locking hex nuts have been replaced though. Unlike the E34S M5, the bolts are 8.8 rated. With other words, torque them at 81Nm instead of 110Nm.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img540.jpg]

The PAS-pump has been cleaned and inspected after which new brackets were fitted.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img541.jpg]

The PAS-pump back in its place; the spanner rail and idler have been replaced with new parts not only for cosmetic reasons, but also to allow easy and precise adjustment. The old parts simply were corroded to much.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img542.jpg]

Many thanks to member Miles for the pictures of #411 that he send me two days ago. I didn’t make enough pictures whilst disassembling the PAS-pump and AC-pump so his pictures were a much needed reference for the reinstallation of the PAS-pump.

The following picture shows the main-earth cable (red arrow) and the PAS-pump back in place (green arrow).

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img543.jpg]

The next item on the list is the installation of the AC-pump.

I have encountered another problem whilst installing the AC pomp. I orderded new spanner-brackets, but unfortunatelly one of them is no longer available.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img545.jpg]

This is not just a cosmetic repair as the idler-rail has been damaged beyond repair. My dealer checked the inventory-list in Holland and it is not available anymore. grrrrrrr

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img546.jpg]

I will check with some of the scrapers if they can help.

The following picture clarifies David’s point. The mounting holes of the hardy disk are directional and marked with an arrow that should point towards the respective mounting flange. I have marked the arrow by outlining it in blue.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img547.jpg]

The repair microfiche explicitly mentions this point, but for some reason, I missed the instruction whilst installing it in April 2008. Thanks Davidoli for pointing me to this. Furthermore; another member pointed me to the missing washer plates. Although it is a fact that washers prevent strain on the hardy disk itself, neither the parts catalogue nor the repair instructions mention that washers should be installed.

Next to this corrective measure, I finished some minor points like the pulley on the PAS-pump and the reconnection of the power steering hoses to the pump. The pulley still is the same part as before, but I had it sandblasted, galvanized and powder coated.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img548.jpg]

I have set a milestone for the end of October after which a temporary change in my private situation forces me to temporarily halt the work on #231. I have known this since last summer, but I have included this break in my planning Anyhow, the milestone is to finish all the required work that is needed to remove #231 from my four-column lift.

Still to do for reaching this milestone:

1: Install main heat-shield between the exhaust manifold and the right front chassis-beam.
2: Install the oil-filter head and replace its oil-pressure switch.
3: Reconnect the oil-cooler to the oil-filter head.
4: Fill engine with break-in oil (15W40 mineral) with new filter.
5: Find a new spanner-rail for the AC-pump (potential showstopper for the milestone).
6: Install the clutch-slave cylinder and the sensors on the gearbox.
7: Connect the reverse gear wiring-loom to the gearbox
8: Install the exhaust system.
9: Torque the sub-frame-and suspension bolts to specification.
10: Installation of the radiator.

I think this can be done in about two evenings.

During the last two evenings, the points on the todo list for reaching the already defined milestone were partially dealt with.

Prior to the installation of the starter engine, it has been inspected and cleaned. The brushes still have 50% life left so that is not a risk in years to come. The shaft has been cleaned and greased prior to its reassembly and reinstallation onto the engine block.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img553.jpg]

Another completed point is the water-pump-pulley. This part has been sandblasted, galvanized and powder coated, just like the PAS-pump pulley.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img551.jpg]

Before installing the oil-filter head, I had to remove the remains of the old gasket. Removing the 24year-old seal was not as straightforward as it appears. The surface of the mating area with the engine block must be flat as otherwise leaks occur. I also installed a new oil-pressure switch and a new ground-return lead (from the alternator).

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img552.jpg]

The current status of the outstanding issues in this milestone is:

Completed issues:

1: Install main heat-shield between the exhaust manifold and the right front chassis-beam => Done (yellow arrow)
2: Install the oil-filter head and replace its oil-pressure switch => Done, (see picture above)
3: Reconnect the oil-cooler to the oil-filter head => Done, (orange arrow).
4: Install the clutch-slave cylinder and the sensors on the gearbox => Done (red and purple arrows)
5: Installed one of the tensioner-bar of the AC-pump => Done (green arrow)
6: Find a new spanner-rail for the AC-pump (potential showstopper for the milestone) => Pending.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img550.jpg]

Still to do:

1: Connect the reverse gear wiring-loom to the gearbox.
2: Fill engine with break-in oil (15W40 mineral) with new filter.
3: Install the exhaust system.
4: Torque the sub-frame-and suspension bolts to specification.
5: Installation of the radiator => This point will be moved to the following milestone.

Contemplations:

1: I am contemplating the replacement of the entire engine-wiring loom with a new part. This will save me the hassle of overhauling the old wiring loom.

MENOOO!!!!! das versteht doch kein mensch ! kann das keiner übersetzen oder können hier alle so gut englisch?

Zitat von Klaus 66

MENOOO!!!!! das versteht doch kein mensch ! kann das keiner übersetzen oder können hier alle so gut englisch?

Dieses bericht wurde primar geschrieben fur m5board und ich hab entweder zeit oder lust um dies in ein andere sprache zu veroffentlichen.

Zitat von Nico/L.E.

My own car has the same color and looks almost like a twin of yours. Apart from the wheels.
And its nice to see that you take so much care of your E28 M5.

Good luck! Nico
..i bought my own E28 M5 in Amsterdam just a year ago.

Danke Niko,

Lachssilber (203) ist fur der E28 M5 der weitverbreiteste farbe. Aber ja, mit nur 588stck sind das nicht viel weniger als z.b Daytona-Violet fur dem E34 M5 3.8

Amsterdam also. Welche FGN wenn ich fragen darf. Ich weiss das #004 und #588 auch in die Niederlande sind. Zufallig sind beide auch lachssilber.

he cool! google übersetzer kannte ich noch nicht. danke oldie

I don't really want to repair the engine-wiring loom, so I bit the bullet yesterday and placed my order for a new engine-wiring loom. The system indicated a price of 462 Euro ex VAT so we didn't really expected it to be NLA. But fifteen minutes later this was confirmed by BMW Netherlands. Now I have no other choice then plan for a refurbishment of the existing wiring loom.

The good new is that the crank-sensor has become significantly cheaper and is available. The existing part has been damaged by some more-on in the past who covered-up his mistake. Not a very good idea as this causes a disruption in the shield and thus reduces the immunity against electro magnetic interference.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img341.jpg]

According to the parts catalogue the price is 209 Euro (ex VAT), but that has been reduced to 79 Euro ex VAT just recently. A no brainer if you ask me.

I was pleasantly surprized with the reduced price for a new crankshaft TDC sensor. Just 30 Euro ex VAT means a saving of roughly 180 Euro ex VAT compared to the old part. The downside is that the connector for plug-in to the engine wiring loom is not supplied. This means some hand-work.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img555.jpg]

This puts the condition of my old sensor in another perspective. I assumed it was damaged during previous engine work, but with the new knowledge in mind I can only conclude that BMW supplies the sensors without the connectors. This means you have to buy the connector-shell, the connector-pins as well. As I could not find these in teh ***, nor could my dealer the only option is to cut the old connector and reuse it.

This must have been the problem of a previous owner as well as the longitudal cut in the heat-shrinkeble tube is man-inflicted. The quality of this work is very poor. My five-year old boy does a better job if I may say so.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img341.jpg]

I cut the old wires about 7mm from the connector shell. Removing the old connector pins will only result in damage so I decided against that. I stripped the leads roughly 3mm to find out the copper standed wires were corroded to such an extent that tin-leveling was not possible. I removed the oxidation with pure alcohol and tinned the leads with plain PbSn solder during which I manually added flux-solvent. With other words, not a simple process, but mandatory for resurecting these old wires.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img556.jpg]

After preparing the old wires, I connected the wires of the new-sensor to the old connector and isolated the individual wires with heat-shrinkable tubes (1608 type 50% crimp). When that was done, I isolated the joint with heat-shrinkable tubing as well (9547 type 50% crimp). This matches the old OEM finish.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img557.jpg]

This will provide for a reliable long-term solution for years to come.

The property class of a metric (carbon) steel bolt is indicated in two numbers separated by a dot. The first number before the point indicates the maximum tensile strength expressed in hecto-Newton per square millimeters. The second figure behind the dot indicates the ratio between the minimum yield stress and the minimum tensile strength, times ten. With other words, the commonly used 8.8 property-class has a minimum tensile strength of an 8.8 bolt is 800 N/mm2 and a minimum yield strength of 640N/mm2.

In the European automotive industry, property-class 8.8 is commonly used and where necessary (e.g. high stress), 10.9 or even 12.9 is applied, but 8.8 is the minimum. This rules out the general bolts that you can find in your local hardware store; these are generally no better then 4.6 or 4.8. These are OK for general non-critical applications, but generally not suited in cars.

This also is the reason why stainless steel bolts are not used in cars. Stainless steel has a much better resistance to corrosion then surface treated carbon steel, but does not have the high tensile strength from a steel bolt. However, for non-critical applications, stainless steel bolts may be used to rule out the concerns of corrosion. One such place is the crank-sensor. It is fitted with a single M5x12 bolt that can be fastened with 6.4Nm max. But 5Nm will also suffice and this allows the use of a stainless steel bolt of A2 property class. Do not use the commonly used A1-class as these allow less then 40% of the tensile strength of an A2 class bolt. The allowed 2.4Nm simply is too low, even for a simple sensor.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img558.jpg]

I also made a start with the overhaul of the engine wiring-loom by cutting the damaged section. The plan is to make an entirely new branch to length and solder it onto the engine-wiring loom. The branch that has been cut will be kept for future reference. It is needed for properly installing the connectors for the three temperature sensors.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img560.jpg]

From each wire, I cut a section of roughly 1cm in length to determine the exact color-coding. If possible, I will source new wiring with the same color-code.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img561.jpg]

To determine the condition of the copper stands, I stripped the insulation of one wire. Apart from the expected oxidation, the conductor is pretty much OK. This is good news as there is no need to strip the wiring-loom any further in this branch.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img562.jpg]

More worrying is the insulation of the main-supply lead for the starter-relay. The insulation is ******* due to aging and conductive losses, or simply heat. Even though that the operating voltage just is 12V+20% and the required creepage distance is less then the depth of the cracks, that is no more then a layman’s approach.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img563.jpg]

In reality, the load is inductive and during switch-off, the voltage will rise according to V = L*dI/dt. Depending on inductance of the load and change of current during the switching time (dI/dt), a voltage transient rising far above the battery voltage will be induced. This transient voltage can be in excess of several hundred volts and with the insulation damage, a break down to another conductor may occur. This can eventually lead to damage of electronic parts.

In fact, these cracks were the reason for me to prefer a new engine-wiring loom, but since these are no longer available, I need to replace the conductor. This requires the entire disassembly of the middle branch, which is much more difficult then replacing the branch for the temperature senders.

My plan is to create a list of the required parts and create a schematic of the circuit before further disassembly.

Last but not least the alternator; it has been replaced in the past as it lacks the BMW part numbers. It is however a genuine Bosch part. From a technical point of view, there is no need to replace it, but I do not like the corrosion on the pulley and the blades. A new alternator is 320 Euro from BMW and 240 from a Bosch specialist (rebates excluded).

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img564.jpg]

The brushes still have enough life left in them, but they differ in length as can be seen on the following picture.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img565.jpg]

After removing of the pulley and the cooling-blade, the alternator looks pretty much OK and just needs some mild cleaning.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img566.jpg]

If the cooling bade and the pulley are available as separate parts, I will simply replace them together with the brushes and the interference suppression capacitor (22uF/100V).

As already writen in the previous post, I made the decision to reuse the alternator. BMW does sell a revision set for the rotor shaft. It contains most of the required parts. I write most Since I go one step further and also want to replace the alternator's suspension, i.e the rubber-and metal bushings, the bolts, the fan-blades and the pulley.

I started with the removal of the front-housing by removing the four bots (red arrow) and the four green screws.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img570.jpg]

Since the froont-housing is pressed into a ball-bearing, a bearing-puller is required for removal.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img571.jpg]

Just a quick look into the alternators internals. Clearly visible are the rotor and the stator with the copper windings.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img572.jpg]

A lot of parts for just the alternator. Ironically, BMW seems to have increased the MOQ values of some parts. Whilst I can live with that for simple bolts and nuts, this is rather stupid for a spanner rail (red arrow).

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img573.jpg]

After cleaning both front-and rear covers, I reassembled the alternator. Already looks much better.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img574.jpg]

I still had to press-fit the new bushings for the alternator's suspension in the front alternator housing.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img575.jpg]

With the new fan-blades and the new tensioner-rail, the alternator looks so much better. I now have to wait for the replacement pulley and the voltage regulator. I expect these to arrive later this week, after which I can install the alternator to the engine.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img576.jpg]

As I wrote in an earlier post, I didn’t really feel the need to replace the alternator as I suspected it to be much younger then the car itself. This is supported by the date code on the rear housing that proves the alternator was manufactured in weak 17 of 1996. This means that it was no more then four years old when I bought #231 in spring 2001.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img577.jpg]

Nevertheless, a Hella voltage regulator does not belong on a Bosch alternator so I simply replaced it with an appropriate device. I did not source this part from the dealer as they charge twice as much compared to a Bosch specialist (roughly 36 Euro ex VAT).

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img578.jpg]

Installation is rather straight forward, if one does not own an M70 powered BMW at least (LOL).

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img579.jpg]

As break-in oil I selected a plain mineral oil with the specifications prescribed in the M5 manual addendum (viscosity 15W40; approvals API SFCC/SFCD). I specifically selected an oil-type that is specially suited for break-in purposes. To many of you, manufacturer Eurol may be unknown, but they are located in my village and have an excellent reputation in the automotive industry.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img580.jpg]

I first filled the oil-filter house with new oil before placing the new filter. Unlike with the S38B36 and S38B38, filling the oil filter house on an M88/3 or S38B35 can cause a spill, but I’d rather fill it before cranking.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img581.jpg]

The bolt should not be torque’d with more then 30Nm as otherwise the O-ring between the oil-filter head and oil-filter house will be squeezed. Please note the hollow bolt.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img583.jpg]

The final result.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img582.jpg]

After the Sinterklaas-party at my inlaws this morning, I drove to Leeuwarden for a visit to IvoC, a fellow E28 enthusiast and parts-collector to pick up an AC-spanner and an engine wiring loom from a E28 535i. Ivo recently shoehorned a fullhouse M67D39 engine into an E28 chassis so he knows his stuff. He also maintains a stockpile of E28 parts and is able to save projects when there is no supply of new parts anymore.

The new AC-spanner. It shows no sign of any corrosion and the tooth from the idler rail is in excellent condition as well. It only needs a mild clean (degreasing) and can be used as-is.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img584.jpg]

After some deliberation I decided to repair my engine wiring loom with a donor wiring-loom with the exact color-coded wires of the engine wiring look from my M88/3 engine. I asked around at the local breakers (even BMW specialist) but got a negative answer. BL-parts in Rijssen does stock a used S38B38 wiringloom, but the expected differences between a Motronic 3.x wiring-loom and a Motronic 1.2 wiring loom that is not really practical. My best bet would be an regular M30 wiring loom from the E24/1 and E28 era. These also use the same temperature senders and the timed-switch (non-catalist version) and after a quick study in the schematic circuits of the E28 535i and E28 M5, these even have the same color-codes so......

Anyhow, Ivo did have a usable engine-wiring loom comming from an E28 535i. The branch to the fuse-box had been cut-off, but the branch to the temperature senders was intact ==> Errr, perfect!

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img585.jpg]

The plan is to transplant the branch for the temperature senders into my M88/3 wiring loom. However, as the location of these parts is different for the M30B35 compared to teh M88/3, I need to strip down the 535i wiring-loom entirely.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img586.jpg]

On a more frustrating note: Last week my dealer confirmed that the alternator pulley for these cars is NLA (already since 1998). It was meant to be a cosmetic replacement and thus not really necessarily. Instead, I dropped of the pulley with some other parts at a metal-treating company to have it bead-blasted and powder coated.

After cutting away the majority of the heat-shrinkable tubing, I managed to isolate and remove the three branches. The length seems a bit short for application in the M88/3 wiring loom, but I managed to remove some wiring with the same color codes in other parts of the E28 535i wiring-loom.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img587.jpg]

Anyhow, not much was left after I reached above objectives.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img588.jpg]

After removing the wiring from the temperature sender/sensor from the 535i's M30B35 wiring loom, I created a new branch for my M5's M88/3 wiring loom. Fortunatelly, the color coding is exactly the same so that eliminated the need for a rewiring scheme.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img589.jpg]

A close-up of the connectors. Each wire-pair is insulated by its own heat-shrinkable tubing before entering the main isolation tube (also heat shrinkable).

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img590.jpg]

The new branch is joined to the M88/3 wiring loom using plain soldering techniques. However, I used a tin-lead with a silver content for better conductivity. Each solder-joint is isolated with heat-shrinkable tube.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img591.jpg]

The solder-joints are compact, allowing the use of plain heat-shrinkable isolation tube to cover the joints.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img592.jpg]

Done.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img593.jpg]