Bericht: Motoruberhohlung E28S M5

About two weeks ago, a small parcel, containing six pistons, twelve intake valves and twelve exhaust valves arrived at my dealer.

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The six boxes with pistons. To reduce the damage risk, I only unpacked one to make some detailed pictures.

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The inscriptions on top. With a 93,60mm bore, the piston to cylinder wall clearance will return to 0,05mm (the last 0,005mm is for the honing pattern). Please note the S38 inscription; it appears that BMW does not distint the M88/3 from the S38 anymore. Judging from the date code, these pistons have been manufactured 12 years ago. By the time I enquired about the availability, BMW had an inventory of twenty-three of these pistons; now just 17.

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Comparison between one of the new-and one of the old pistons.

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The piston crown!

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The bill.

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One of the intake valves.

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One of the exhaust valves.

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Whilst we are waiting for the cylinder head being returned from the metalurgist, the engine shop started with the engine block. The bores have been enlarged to 93,60mm to obtain a clearance of 0,05mm with the new pistons. In the mean time, the bores have been honed as well.

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An important part of a bottom end overhaul is the selection of the bearings. These are available in standard size (60,00mm) and three oversizes (59,75mm, 59,50mm and 59,25mm) in case the crankshaft needs to be machined. As this is not the case with my engine, the recorded measuremets determine the required bearing size.

However, the bearings are avalable in two color codes (red or blue). This is a classification that depends on the production tolerance from crankshaft and crank-case. With other words, a cranshaft is supplied with matching bearings. This is determined by the colored dots on the crankshaft that in this case is red.

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Fortunatelly, the colored dots were still visible on this particular crankshaft. If they weren't the BMW repair instructions state that the crank-case determine the required bearings type. In my case, the crank case has red dots as well, thus matching those on the crankshaft.

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With other words, the main-bearing selection is unambiguously determined by the crankcase, cranshaft, but also the markings on the old bearings. This is a bit more difficult for the piston rods. As clearly can be seen, these have red color dots as well. However, matching bearings are not available anymore.

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Only rod-bearings with the yellow color code can be bought. This is worrying, but I don't have a choice so I have to do with these. Given the fact that the tolerance of these bearings is less then 1/1000 of a millimeter and the recorded journal diameters indicate the clearance ending up within specification, plastigage measurements must provide the empirical proof.

In the mean time, I have ordered all the parts that are needed to finish the short engine block. This includes the gasket sets, sprockets, guides, timing chain, bearings and all the bolts and nuts to complete the short engine. I also am preparing three scientific documents that decribe the failure mode analyses and the rebuild with underlying proof of all the choices that have been made, including the overhaul proces.

After boring and honing the short-engine in the week before, the machine shop removed the water-channel coverlids and cleaned the engine thoroughly, after which it received a finish with application specific black paint. In the mean time, my dealer received the three separate batches of parts that I ordered for the assembly of the short engine.

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To manage this project successfully, I have decided to separate the parts ordering to match the different rebuild stages. This not only gives a better overview of the deliveries, but also reduces the risk of mixing up parts between the few stages. Fortunately, BMW still offers gasket sets for the M88/S38 engine family. Two sets are required; one for the cylinder head and one for the short engine. The gasket set for the short engine is relatively cheap. The stealer wants ~65 Euro ex VAT for it which is a bargain if one considers that both crankshaft seals are included.

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Much more expensive is the cylinder head gasket seat that retails for around 320 Euro ex VAT. But it contains all the required gaskets including the cylinder head gasket (120 Euro ex VAT) and the valve stem seals (45 Euro ex VAT).

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Clearly visible are the two valve stem seal repair kits. In total the cylinder head gasket contains 62 separate parts. Many of the O-rings have a minimum order quantity (MOQ) when ordered as single parts so the gasket set makes a lot of sense.

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The sump has been cleaned and painted in application specific silver paint.

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The same applies for the timing chain cover. Clearly visible is the front crankshaft seal.

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The new pistons have already been installed on the piston rods awaiting the delivery of the new bearings shells.

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All the timing chain related parts will be replaced with new parts. The following picture shows the new crankshaft sprocket for the timing chain and the oil-pump chain.

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The following picture shows the rear crankshaft seal. It is mounted in an alloy cover that is bolted to the short engine. The bolts and washer plates are replaced as well.

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I ordered a new hub as well. The old one contained a small groove, that could be removed by machining, but who bothers at 75 Euro ex VAT. Actually, this is an obligatory part when performing a full engine-rebuild.

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The remaining parts needed for assembly of the short engine have arrived at the dealer today. Monday morning, the engine shop will continue with the assembly of the short engine. The cylinder head has not yet been returned from the metallurgist. The expected delivery time will be three weeks, thus the second week of July. This delay means that I won’t be able to install the engine before my summer holidays at the end of July.

The following picture shows the old and new chain guide-rail (tensioner side). The upper part is the original part, presumably 23-24years old. The lower parts shows the replacement part. Clearly visible are the wear patterns caused by the timing chain.

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A close up of the cracks in the rubber lining.

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The old crankshaft sprocket (left) with the replacement part (tight). I now see that the hub-side of the old sprocket appears to have some damage, but I am not sure about this as the picture only shows a 2D perspective.

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The old parts will be kept for the time being. Clearly visible are the dismissed main crankshaft seal (flywheel side), the old chainguides and the timing chain.

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One of the old main-bearing shells with a date code that prooves that they were manufactured before #231 left the assembly line at the Preussenstrasse in 1985. This also prooves that the crankshaft still is the original part (new crank comes with new bearings). This unlike a statement from a BMW representative who doubted that this was the case for this particular car.

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Suffice to say that the chain tensioner will be sourced from the S50B32 as is described in this reference article.

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With teh arrival of the last missisng parts such as the rod bearing shells, the short engine is now in the middle of the reassembly phase. The six pistons and rods have been installed as can be seen on the following picture.

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Last week, Ronals used the old crankcase bolts, but with the arrival of the new parts he could complete that part yesterday as well. I am not that keep on the black paint on the pipe for the dipstick, but since I want to replace that part as well, I don't care.

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The number of replaced parts increases slowly but steadily.

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By advise of member Stevie, I asked Ronald to soak the new chains in a bucket with oil for a week or two. This will allow oil to creep alongside the pins between the shackles for proper lubrication. This will significantly reduce the start-up wear. If all goes well, TMR can complete the short engine assembly soon after.

In post #275 of this thread, I shared a theory about the engine of #231 being repaired before for some reason. Whilst I was doing some research in the past few weeks, I discovered that the early E28 M5 and E24 M635CSI's were originally assembled with single valve springs that have an realistic chance of failing. This design problem is discussed in detail in a seperate thread about the M88 valve spring risk. When I removed the cylinder head, I found out that the valve springs are of the double spring design so this issue has been addressed on #231 a long time ago.

Furthermore, I have found the conclusive proof that the 93,45mm bore diameter has been determined during the production process. The proof is a '00' inscription in the top-side off the short-engine. This matches the same coding that the TIS uses for an intermediate bore size. The measurements report from TMR confirms this as well.

With other words, the bore-wear is limited to 30um max that is the result of 155k km. Extrapolated to the max pistin to cylinder wall clearance, this means that the short engine could have lasted 510k km before needing a rebuild. However, the piston to cylinder wall clearance has exceeded the maximum value. This simply contradicts so there has to be another explanation.

It is my theory that #231 suffered from a failing valve spring in the first year(s) of its life and that this failure caused one or more valves that dropped and damaged the pistons. In the repair that followed, it is likely that the mechanic missed (or was not aware) of the '00' code on the short engine and just ordered the standard piston set (for size '0'). TMR's measurement report supports this; all pistons measured 93,35mm (max), matching the requirements for size '0' and not '00' that requires pistons with a diameter of 93,40mm.

This proof is only conclusive if I can find markings on the old pistons that proof this. Unfortunatelly, the piston ident cannot be found on the piston-crown. Instead, the piston ident can be found on its top side, however this is coverd by carbon deposits. I removed these and found M88/3 and 10,5 texts. However, I did not find the full text that refers to the piston diameter, but only the last two digits on teh spot were I expected them. Since these clearly reads 35 (and not 40) I have to assume that TMR's measurements re correct.

Shortly after the summer holiday season in northern Netherlands, work commenced on the hart of #231. The cylinder head was returned by specialist CSN in this period.

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The cylinder head as received from CSN in Uden. Although CSN offers a complete overhaul service for cylinder heads, TMR only asked them to route the alloy around the cracks and weld alloy in place.

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Needless to say that CSN work-result is very rough. The required maching, polishing etc will be carried out by the engine shop (TMR in Almelo).

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The result (one combustion chamber) after the first round of machining. This already looks much better, but still requires a lot of fine-tuning. Clearly visible is the crossing between the original alloy and the welded alloy.

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Both M88/3 cylinder heads on top of each other. The lower cyl-head was bought from Andreas Heuer in Germany in November 2008. The upper cylinder head is the original part from #231.

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The short engine has been placed on an engine stand for further assembly. In the past days, TMR completed the assembly of the short engine. Clearly visible is the flywheel.

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The timing chain cover with the hub for the harmonic balancer. I decided against the Frank Fahey hub for the time being as my old hub did not show any signs of being defect and #231 will not be used that hard that the Frank Fahey hub is necessary.

In the past week Ronald from TMR continued with the overhaul of the cylinder head. A main issue were the old valve-guides that although within specification have been replaced with new parts.

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A close up of a randomely selected cylinder with the new valve guides.

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After finely machining and polishing the combustion chambers to specification, Ronald installed the new valve seats.

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The following pictures is not from my M88/3 engine but from some sort of Opel/Vauxhal Ecotec 4pot that needed new valve seats after running a few years on Liquid Petrolium Gas. This pictures shows an unmachined valve seat after installation, but before machining to the correct angles.

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Again a randomely selected combustion chamber. The valve seats already have been machined to the correct specification.

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The following picture shows the combustion chamber from the first cylinder. Clearly visible are two small defects in the alloy. These small craters are caused by gas that gets trapped during the welding process. I have to admit that I am a bit worried, even though Ronald pressure tested the cylinder head at 3bar and gave it the all clear. It is not so much the visible defects that I am worried about, but more the trapped bubbles that I cannot see. I am contemplating a Rontgen analysis, but have yet to make up my mind.

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The following picture shows two exhaust valve seats after being machined to specification. Clearly visible is the sealing ridge with an angle of 45degrees. This must be 1,4mm wide for the exhaust valves and 1,2mm wide for the intake valves. The inner angle is 60degrees, the outer angle 30degrees.

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Just after the machining process of the cylinder head was completed; Ronald proceeded with the installation of the valves, valve springs and associated parts.
Shortly after finishing with the machining process of the cylinder; Ronald proceeded with the installation of the valves, valve springs and associated parts.

When rebuilding the cylinder head of an M88/S14 and S38 engine, it is advisable to replace all the exhaust valves, as these have a hard life due to thermal stress. I know of at least another M88/3 and two other S38B36 engines that recently broke down due to a burnt exhaust valve. It is therefore of the utmost importance to calibrate and if necessary adjust the valve-clearances of these engines at least once every 10k km or at least once per year.

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Although the old stud-bolts could were still usable, I replaced all of them to secure a reliable long term fit. They also give the freshly rebuild cylinder head a much better appearance.

It was not really necessary to replace the intake-valves, as these are not submitted to high thermal stress. But at 35% of the nett-price of an exhaust valve, replacing these is IMHO a no-brainer.

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The following picture shows a randomly selected combustion chamber with the new valves that are properly seated in the valve seats. The smaller diameter valves are the exhaust valves (32,0mm), the larger diameter valves are the intake-valves (37,0mm). Please not the small clearances between the intake valves. The diameter of the valves is the same for the M88/3, S38B35 and S38B36. The S38B38 has intake valves with a diameter of 38,5mm and 32,5mm for the exhaust valves reducing the clearance even further.

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Even though the engine of #231 already had the dual valve-springs installed with the goal to reduce the risk of a break, this cannot be totally eliminated. The risk of a cracked valve spring is typically caused by metal-fatigue that becomes a determining factor for engines that are used at high engine speeds for sustained periods of time. That is the reason why I replaced all valve springs with new parts. The following picture shows the outer and inner valve spring. Please note that the M88/3 uses smaller diameter springs then the S38 variants.

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Next to the valve-springs, I also replaced the spring-pockets, spring plates and valve collets for the same reason as mentioned before. The following picture clearly shows the inner-and outer springs with the spring plate. Also visible are the valve-stem seals.

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Ronald temporarily installed the camshaft-house onto the cylinder-head to enable him to set the valve clearance to the specified range by using the initial shim-thickness of 3,75mm to 3,80mm as used during the factory assembly a long time ago.

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Last but not least a picture from the cylinder head placed onto the engine block. Please note that this is not a permanent install as some timing-chain guides still need to be installed.

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The rest of the work is simply assembling the remaining parts. In a week or two the engine shall be ready.
When rebuilding the cylinder head of an M88/S14 and S38 engine, it is advisable to replace all the exhaust valves, as these have a hard life due to thermal stress. I know of at least another M88/3 and two other S38B36 engines that recently broke down due to a burnt exhaust valve. It is therefore of the utmost importance to calibrate and if necessary adjust the valve-clearances of these engines at least once every 10k km or at least once per year.

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Although the old stud-bolts could were still usable, I replaced all of them to secure a reliable long term fit. They also give the freshly rebuild cylinder head a much better appearance.

It was not really necessary to replace the intake-valves, as these are not submitted to high thermal stress. But at 35% of the nett-price of an exhaust valve, replacing these is IMHO a no-brainer.

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The following picture shows a randomly selected combustion chamber with the new valves that are properly seated in the valve seats. The smaller diameter valves are the exhaust valves (32,0mm), the larger diameter valves are the intake-valves (37,0mm). Please not the small clearances between the intake valves. The diameter of the valves is the same for the M88/3, S38B35 and S38B36. The S38B38 has intake valves with a diameter of 38,5mm and 32,5mm for the exhaust valves reducing the clearance even further.

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Even though the engine of #231 already had the dual valve-springs installed with the goal to reduce the risk of a break, this cannot be totally eliminated. The risk of a cracked valve spring is typically caused by metal-fatigue that becomes a determining factor for engines that are used at high engine speeds for sustained periods of time. That is the reason why I replaced all valve springs with new parts. The following picture shows the outer and inner valve spring. Please note that the M88/3 uses smaller diameter springs then the S38 variants.

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Next to the valve-springs, I also replaced the spring-pockets, spring plates and valve collets for the same reason as mentioned before. The following picture clearly shows the inner-and outer springs with the spring plate. Also visible are the valve-stem seals.

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Ronald temporarily installed the camshaft-house onto the cylinder-head to enable him to set the valve clearance to the specified range by using the initial shim-thickness of 3,75mm to 3,80mm as used during the factory assembly a long time ago.

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Last but not least a picture from the cylinder head placed onto the engine block. Please note that this is not a permanent install as some timing-chain guides still need to be installed.

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The rest of the work is simply assembling the remaining parts. In a week or two the engine shall be ready.

Its has been fourteen months since I removed the cylinder head but with its reinstallation, the heart of #231 looks like an engine again. Within a few days, the rebuild phase is completed after which I can prepare for the next phase; the engine-installation.

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To set the correct timing for the camshafts, the crankshaft must be rotated such that the TDC marking on the flywheel match the TDC marking on the timing chain cover.

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With the crankshaft on TDC, the correct timing is set when both cam lobes point towards each other with a 45degree angle and the TDC markings on both camshafts match the markings on the bearing caps perfectly. This is not an easy task!

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With the engine in the car, the rear panel of the camshaft housing is a real PITA to remove, especially the lower bolts. This is necessary when the gasket between the cover and the camshaft housing develop a leak; not uncommon for the S14/M88 and S38 engine families.

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I love the shiny new look of the exhaust-valve-stems. To bad, one cannot see these in a few weeks anymore.

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The only outstanding issue is the valve-cover gasket that is part of the gasket set for the cylinder head. Although I had the correct part number of the gasket set verified by my dealer before ordering, the supplied gasket only fits the S38 engine that has a dual-row timing-chain and thus a slightly larger chamber for the cam-sprockets. TMR returned the gasket to the dealer with the request to supply the correct M88/3 part. This will take a few days.

With the last issues being sorted out by TMR this week, I picked up the revived heart of #231 and took it to my 'workshop'. IMHO, TMR performed excellent with the overhaul of this engine. It just looks brand-new.

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Needless to say that I am very happy with the result and I am eager to start with the planning of the installation phase. I already wrote the technical specification and the requirements, but I have to wait for the new waterpump, new clutch etc etc before I can start working.

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Although the rebuild-project has been completed, I will continue posting updates about the installation, break-in and testing phases.

After TMR delivered the freshly rebuild engine just a week ago (see this thread about the engine rebuild), I can prepare myself for the reinstallation of the heart of #231. I have scheduled this task for Saturday September the 26th, but before that can take place I have to replace some parts.

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Since the water-pump has been replaced by a main dealer in 2002 and since then, only 3000km have been added to #231, I expected the old water pump to be in excellent condition. But when I removed the existing pump prior to pulling-out the engine block in December 2008, I was surprised (and shocked) by the condition of the rotor, hence why I had to by a new one. The following picture shows the old-and new water pumps. Suffice to say which one is which!

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The rotor itself is not made from a very high quality material; it’s cast from some sort of steel-alloy that is prone to minerals. I suspect that in 2002, the main dealer just added the common 50/50 mix of plain water with glycol-based anti-freeze. The problem with glycol is that its cooling-capacity is roughly 70%, hence why it is mixed with plain water. Although this is a factory approved filling the quality of crane-water differs from source to source. After a mere 1000km and 2.5years, I drained the coolant system entirely and filled it with a low mineral coolant which although more expensive gives a much better protection to corrosion. This was either too late or not sufficient.

Judging from the date code on the old clutch-plate, it was installed in 1986. If one compares the abrasive material on both sides (red arrows), one can clearly see that the thickness on both sides is different. Based on this fact, I estimated that its remaining service life at roughly 10000km.

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Given the low annual mileage of #231, 1000km equates to two to three years, but with the upcoming break-in phase in 2010, I have to drive at least 5000km. Chances are that I have to replace the clutch one way or the other so I decided to install a new OEM clutch whilst the engine is out of the car. The following picture shows the new clutch-plate in the box. Clearly visible is the thickness of the abrasive material.

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A side-note: Given the fact that many of our E28 M5’s have been manufactured in the eighties, I do not know for sure weather or not the original clutch is asbestos free. Therefore, use extreme caution when removing the old clutch.

I managed to install some auxiliary parts to the engine this evening. I started with the water pump and its seal. The six M6 bolts are bolted with a torque of 10Nm. Please note that the engine-shackle has been removed to gain the required clearance.

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The next part is the engine-shackle. There are two bolts. One M6 (10Nm) and one M8 (22Nm).

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Since the old heat-shield was cracked, I bought a new one. Its fitting is straightforward.

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Last but not least the new Sachs clutch. I aligned the clutch-plate visually, but will check this with the alignment tool that is confirmed for delivery on Tuesday. When that is done, I can tighten the pressure group with the six inside-hexagon bolts.

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I decided to wait with the exhaust manifolds until the engine is in the car to have a better maneuverability of the engine and gearbox combo.

My clutch-plate alignment tool arrived yesterday, a day earlier as planned. It’s a rather simple device that allows the centering of the plate to the pressure group before assembly on the flywheel. The centering is required as oherwise the gearbox prise-shaft won't fit.

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After the alignment, I fastened the (8.8 classed) six fillister-head screws with 24Nm (Note that the S38 uses 10.9 class that have to be torqued with 37Nm).

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The next item on my agenda is the replacement of the prise-shaft-seal. The old part leaked causing a small spill in the bell house and on my floor.

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The old seal popped out without much hassle. I cleaned and sanded the mating area of the seal to remove the surface rust before press-fitting the new seal.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img512.jpg]

The price shaft cover with seal in situ with new bolts and washers. Note the small plastic ball-pin to the right. This is the stop for the release-bearing lever and should be replaced when replacing the clutch.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img513.jpg]

The release bearing, the release-bearing lever and the spring-clip installed. The prise-shaft needs to be greased, but when that is done, the gearbox is ready for its marriage to the engine.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img514.jpg]

Last but not least; the new shifter-lever with bearing. The new part is a few centimeters shorter then the old one, but matches the one from the later E28S M5’s. This should be an improvement.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img515.jpg]

After last weeks preparations, a small team consisting myself and members Billie_S38, RobertK and Javi82 installed the freshly rebuild original engine in #231. I hoped to make some more pictures of the entire proces, but as it was a labour-intensive proces I a only managed to shoot four pictures today so the detailed pictures will follow later.

We started with the assembly of the gearbox to the engine, which was not really difficult, but we had to make sure the crankshaft wasn't moved. Prior to the assembly, the prise-shaft and the relevant surfaces of the fork-lever were greased with molycote. All new torx bolts have been used. There are eleven of them with different sizes, but you'll need sockets E10 and E12. The M8 bolts are fastened with 22Nm, the M10 bolts with 43Nm.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img516.jpg]

With the gearbox installed, the engine crane needed to lift ~300kg. This exceeds the only usable capacity of the crane to lift the engine high enough. It took us some puzzling to figure out the best way to proceed and here member Javi82 provided very valuable insight with his hands-on experience. Member Billie_S38 was underneath the car to properly allign the propellorshaft to the gearbox. Member Javi82 positioned the engine with help of member RobertK whilst I operated the engine crane and supplied the required material.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img517.jpg]

After about an hour, the engine was at its final place after which we took some time for a coffee break and to take a look at Javi82's E34S M5 and some petrol talk. As said, more detailed pistures will follow later.

Last but not least: Many thanks to members Javi82, Billie_S38 and RobertK for the valuable help and assistance. :cheers:

Bestimmt ein toller Bericht. Bin inEnglisch aber ne totale Niete . Wie oder wer kann sowas Übersetzen, damit ich auch mitreden kann.

In a previous post, I reported about the reuniting of the original M88/3 engine with the chassis of #231. In an offline exchange of thoughts with member Javier, we discussed about the best approach to install the engine.

Javier preferred to install the engine with the exhaust manifolds preinstalled whilst I preferred to install the engine with the gearbox installed. Both gearbox and manifolds preinstalled won’t fit from above so I had to make a choice. Although I have to agree with him that it the gearbox imposes less constraints for installing afterwards compared to the exhaust manifolds, I decided against that as I am not accustomed to lifting a +50kg gearbox above my head, nor do I want to ask that from other people as well.

The exhaust manifolds are extremely light by comparison, but are not a serviceable part. The constraints are the limited amount of space between the front wheel arches, the tubing for the AC system and the engine itself. This constraint can be waived by lifting the engine from underneath. I found it convenient to keep lift at roughly 1.5mtr so I could reach the exhaust manifolds from underneath. I lifted the engine with the engine-crane and a wooden block to prevent damage.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img518.jpg]

The second constraint is the limited amount of space to tighten the 9mm copper nuts. It’s a time-consuming and PITA job, but by installing the manifolds one at the time, only two nuts are difficult to reach. The other nuts on the bottom can be reached from underneath which is possible with the car lifted.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img520.jpg]

Although the existing engine mounts were in pretty good shape, I didn’t bother and replaced them nonetheless.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img521.jpg]

Please note that it appears as if the parts catalogue does not list the left engine mount as available, but these share the same position with a drop-down handle in the explosion view after which two separate part numbers are listed.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img522.jpg]

That´s realy awesome!!!

Hope my Engine will shine like yours after the rebuilt!

By installing the exhaust manifolds one at a time, I hoped to simplify the fastening of at least two of the difficult 9mm nuts. This didn’t really work out as the manifold of cylinders #4, #5 and #6 imposes significant constraints to the correct installation of the other exhaust manifold. It can be done, but it requires the removal of the right engine mount and its support, heat shield and the alloy frame for the distributor.

The engine then needs to be lifted high enough to gain the required clearance for a correct feed-through of the long exhaust manifold for cylinders #1, #2 and #3. I used the AC-pump bracket as lifting point.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img524.jpg]

After some puzzling, the bugger was ready for the final installation. However the header from the fourth cylinder is a few millimeters too thick for maneuvering the header from the third cylinder onto the exhaust ports with the bolt-ends installed.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img523.jpg]

Having said that, I am happy to have replaced all the bolt-ends as well as I had only one option left; unbolting the already installed manifold to waive the constraints for the other manifold. This cost me about half an hour after which both manifolds were pre-fitted to the cylinder head..

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img525.jpg]

Fastening the twenty-four nuts required another 1.5hour and various tools including half-open and closed 9mm wrenches and small ¼” ratchet with the proper extension tools. Fastening these nuts is more easily with the engine lifted as far as possible, so I kept the engine-lift underneath the bracket for the AC-pump. At half-past eleven yesterday evening, the job was done.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img526.jpg]

I took a picture from underneath to show the recent progress.

[Blockierte Grafik: http://rwoe.150m.com/tmp/20080301/img527.jpg]

1: I reinstalled the heat shields on the exhaust side (green arrows). I replaced the heatshield on the engine mount (light green arrow) as the old part was cracked. Although it would be nice to replace all the heatshields with new parts, this was not really necessary as the two other heatshields were OK.

2: As can be seen, the PAS-pump and AC-pump (red arrows) are still kept in place by securing-belts. I have placed an order for all the required parts to assemble these on their respective brackets. The PAS-pump and the AC-pump require refurbishment before reinstallation.

3: The slave cylinder (blue arrow) has yet to be refitted. I will replace it in the future, but not right now as I have set explicite goals to avoid unnecessary work in the context of this engine-rebuild.

4: The small orange arrow points to one of the oil-channels. I have seen pictures were this opening is covered by a nut and I have seen some pictures were this is not. The parts catalogue does not list any part so I have placed this subject on the outstanding issue list.

5: I also will not replace any suspension parts, even though they are now easily accesible. They are beyond the scope of this project. My focus is finishing it. After the #231 passes the break-in phase, I will reasses their condition.