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Lovely car , Raymond and a deserved spot on Exhibition. I have read Your threads with interest as I love the E28 M5 . Since selling my E34 touring (regretted that many times ) I have "a spot open" for a hobby car.
Hence slightly off topic; I have had on and off discussions With an E28 M5 owner for over 10 years now about me buying that car.
I have mailed you (via M5board) and sent PM without receiving a responce. I understand that you are a busy man , but the questions I have are quite "simple" , mostly about value, as I don`t wish to come up with an offer that is offending. If you wish to answer the questions I have, we could PM about them?

With best regards
Sakke
 

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And also I have to Express my admiration , You are very focused and systematic in the restoration Project. The best part is that you take the time to document everything in detail AND share it With rest of the community!!!!


Best regards
Sakke

(thanks for the PM - mail sent)
 

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Discussion Starter #204 (Edited)
Six years have passed since the engine of #231 has been rebuild. In total, a little over 15000 kilometres were added, meaning that an inspection II service was due for this year. Just prior to the summer holiday season, I used #231 for a driving tour with ‘BMW Klassiek’, one of the official BMW clubs in the Netherlands which I joined as a member some time ago.



This driving tour took us from the Rotterdam area alongside the Dutch river-delta towards Zeist, in the center of the Netherlands. The character of this event is more leisure driving, but to be honest, most of the Netherlands has a level of congestion that doesn’t allow for spirited driving anyhow. There simply is too much traffic at any time of the day, especially in the Randstad area. This trip went uneventful and #231 performed flawlessly.



During my holidays in Austria, I defined the Bill of Materials for #231’s inspection II service submitted this as purchase order to the BMW dealer of my choice. All these parts were stock items and delivered within a single day.



The high level scope of an inspection II service entails the following:

1. Replacement of the engine oil (including oil filter)
2. Replacement of the coolant
3. Replacement of the gearbox oil
4. Valve adjustment
5. Replacement of the fuel filter
6. Replacement of the air-intake filter
7. Replacement of the spark plugs
8. Replacement of V-belts

Because we replaced the engine oil less than a year ago and the current fill has covered a mere 1642km, I considered this done. I then started with the removal of the six spark plugs.



If one takes a closer look to all six of them, their spark plug image does not differ that much from each other; in fact, they are nearly identical. Judging the black sediment around the ground-strap, the engine runs on an excess of fuel, but this is normal for an M88/3, let alone one that operates on an Air to Fuel Ration of circa fourteen to one. The same applies to the brownish coloration off the porcelain insulator, which points towards an enriched Air to Fuel Ratio under load, which also is expected.



We then removed the valve cover for the mandatory check of the valve-clearances. All twelve of the intake valves were spot on (0,30mm), but four of the twelve exhaust valves needed some minor correction, which given the fact that there are subject to a high thermal stress is normal, even after a mere 15000 kilometres.



Suffice to say that we also replaced the gaskets of the valve cover. Even though the old gaskets were a mere 15000 kilometres old, the valve cover was opened for a few times during the running-in phase so their replacement was overdue anyhow.



The air-filter also needed replacement, not also because of its service life, but also because the foam circumference has dried out because of its fifteen years of age .



At that time, I had to reposition #231 before my two column lift for which I had to start her, however despite a few attempts she cranked but did not start. This came as quite a surprize as before the holidays, she ran like a clockwork. We then checked the basic parameters (ignition, fuel, compression and air). Ignition turned out to be OK, as well as the engines compression and air so we had to check the fuel supply for which I connected the fuel-pressure gauge.



Warning: Measuring the fuel pressure on an M30/S38 engine requires disconnecting the high pressure fuel supply from the fuel bar and inserting the adapter-set with the Schreader valve. Without proper measures, chances are that fuel will leak. Always keep a fire extinguisher nearby just in case fuel escapes and gets into contact with hot engine parts (e.g. exhaust).

In order to measure the fuel-pressure, we bypassed the fuel-pump relay. This allows the pump to operate without cranking the engine. The outcome of this test was that in open-loop, the fuel pressure was 0,5bar maximum. This is way too low because the Fuel Pressure Regulator maintains a constant pressure of the fuel-rail of 3.0bar referenced against the pressure of the intake system.

When the fuel pressure is too low, the car won’t start, yet there may be two causes. First, a broken fuel-pump (the E28 has two) or second, a broken Fuel Pressure Regulator. Since the fuel pressure exceeded six bar with the fuel rail blocked, both fuel pumps are considered to be OK.



After repeating the fuel pressure tests for verification, we came to the conclusion that the fuel-pressure regulator broke down. This wasn’t really expected because this part was a mere twelve years and 17000 kilometres old, yet it is not unknown that they fail suddenly. Maybe it is the aggressive nature of modern fuels that is to blame…. I just don’t know but didn’t expect this.



So we had to order a new one from the stealer and again there was a little catch. Whereas I bought a new FPR for a mere 48 Euro’s in 2005, these things now list for 162 Euro. One might say that the dealer is to blame, yet I found out that the list price from manufacturer Bosch is even higher (192 Euro). I can see the rationale, yet this is something we have to live with.



The replacement of the FPR did resolve the difficult starting, yet did not resolve the stalling and dying engine after a few minutes of running. We again check the fuel pressure, but with 3.0bar this was now spot-on, so we checked the ignition again for which we first performed a visual check of the leads and the distributor.



The silent observer already has spotted the ionized contact for the supply lead connection. We checked the impedance of the contacts, which had turned into a high (capacitive) impedance rather that a low (resistive) impedance.



Since I always keep a spare distributer, I reinstalled one and replaced the supply line from the ignition coil to the distributor with an old item from my E34S M5. This allowed the engine to start and run correctly. There is no need to replace the entire High Voltage wiring loom; we can do with the replacement of just the supply lead. The PO for the required parts has been sent out. They will arrive within the next few days.



Again suffice to say that we replaced the fuel-filter as well, which sits underneath the car next to the second high pressure fuel-pump.



I use a special type of (low nitrate) coolant (Eurol XL36) that has a yellow coloration. We drained circa 9,5 litres from the engine and flushed it with plain water afterwards. However before draining the old coolant, I put the tip of member “bmwdirtracer” to test for electrolysis of the coolant into practice (refer to this thread for more details).



The old coolant (six years and less than 13000 kilometres) measured a voltage potential of circa 85mVDC between the coolant and the engine ground. According to the criteria of member “bmwdirtracer” this is nowhere near being critical (200mVDC), yet the manufacturer of the coolant recommends a replacement interval of no more than five years so there may be some inconvenient truth. For comparison, I performed the same test on my E34S M5 of which the coolant is still less than two years. This resulted in a measured voltage of circa 25mVDC. After filling the coolant system of #231 with new coolant, the potential between the coolant in the reservoir and the engine-ground was less than 10mVDC.



And to be honest, I have proof of the effects of Electrolysis on the Lampredi Twin-cam turbo engine (same as used on the Lancia Delta HF Integrale) of my father’s Fiat Croma turbo i.e that we recommissioned into service after being stored and forgotten since 2002. The only plausible explanation for the damage on its cylinder head shown by the above picture is Electrolysis and yes, the coolant has never been replaced since the car was delivered new to my father in 1988!



We had to rebuild the Lampredi Twin-cam, which shares some design elements with the S38/M88 engine family. In fact, the Fiat group holds a patent on the valve train design with removable shim-plates.



Back to #231; in the meantime, we also replaced the V-belts. We are only waiting for the parts to resolve the failed connectors of the ignition systems supply-wire. Remains the exchange of the gearbox fluid for which I have yet to order some Redline MTL.
 

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Discussion Starter #205
Reinstated the URL's to the pictures for a second time; this time following a critical issue in my photobucket account, which photobucket acknowledged, but could not resolve.

Please note that this also applies to all my previous postings that date back to 2004 or so. I will repair the links, but this may set me back for about at least a year.
 

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Since you seemed to thoroughly enjoy the rebuild process on your M88/3 would like to do the same to mine, I wont charge you , I'll even pay for shipping :)(y). Fantastic job.
 
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