Monday, March 30, 2009

THE PLAYBOY'S RIDE : BMW 325I (E46)


One of the most distinctive feature of this beemer is the sleek looks that captivates from all angles. Perhaps that is the main selling point besides the roar and draw of the infamous in-line 6 that BMW is known for.





When things are new, there can be nothing short of bliss on this ride, coupled with envious stares from the outside world.







Only with the blinking "Service Reminder" that the driver is yanked from 7th heaven back to the real world, that anything that goes up - must come down.






The costs for maintaining this baby can be quite substantial if the owner so choose to send it back to the "professionals". Note the overflowing power steering reservoir - that's the only thing that is not dulled by dust accumulated in this engine bay.





One of the things that I have observed in general - the engine bay is always dusty and dirty. That is because washing is not encouraged, and some car mfg. even spelled it out in the owner's car manual. Indiscriminate washing can cause unexpected damage, for example, if the water gets into certain sensitive areas, or washing when the engine is still hot.



So, if you ever wanted to "wash" your engine compartment, bear that in mind, or get a "pro" to do it for you. This is how the engine compartment looked like after a wash. The engine top covers and air filter housing were removed earlier to be washed separately.





IRRESPONSIBLE WORKSHOP MECHANIC(S) CAN BRING DISASTER !
Somebody attempted to remove the main viscous fan from the water pump pulley that is almost standard equipment on all beemers, and left one of the 4 bolts untightened. Initially, when the car came in, I noticed the abnormal "crunching sound", which turns out to be the pulley wobbling on the shaft. Notice the 32mm nut that secures the viscous coupling fan (photo). That nut must come off before the main drive belt can be replaced.

Well, here it is, with the viscous fan and shroud removed. Everything is laid bare for servicing.







For such a magnificent machine, it is a shame to use a low quality filter. Judging from the color, sludge and loss of viscosity, either the engine oil has been used on an extended service interval or a low grade oil is substituted.





A new "Mahle" filter installed after the housing is cleaned. Nothing looks better than having a top end product fitted the right way. Nothing rides better too, knowing the best spare part has been fitted, and the right job has been done.





Notice the accumulation of sand dust at the bottom of the air filter housing. Apparently, the practise of washing the air filter housing prior to replacement with new air filter is not commonly practised (judging from the receipts of various workshops this car have been to).




The air filter housing, the engine spark ignition and fuel injection covers stripped out for thorough cleaning with detergent and water jet wash. The bottom engine cover (underside panel) was washed so that I could use it to troubleshoot any future oil leaks by observing the stains (planning for future inspection).





If you have not seen an Iridium spark plug, here it is. Notice also the accumulation of engine oil at the threads, suggesting the period of usage.





This view is enough to sink the Titanic, if you happen to have bought the car and your favorite mechanic snapped this photo for your viewing pleasure. The engine oil stains suggests oil seepage from oil sump gasket and bell housing (flywheel / torque converter housing) , indicating a major overhaul is expected.




My take on this minor seepage was that, the previous owner has been using synthetic engine oil on a 130,000km car, which may be the root cause. Synthetics are excellent penetrants, especially when the temperature is raised up. I replace the oil with 50% Fuchs CEF (Molybdenum) and 50% Fuchs Racing to soothe the intensity of the CEF's solid lubricant additives. The underside of the engine is then flushed clean, and subsequent test drives reveal no leaks.

After service completion, I used mOByDic tool that connects directly into the on-board diagnostics connector below the dashboard, that links directly to the car ECU(s).






A PC is hooked-up to the other end of the diagnostics tool. After engine start-up, a full scan is done via the PC to confirm all "OK". And lastly, with great reluctance, deliver the car back to the owner. Like the infamous speech from the hotel manger to Edward Lewis in 'Pretty Woman' : "It must be difficult to give up something so beautiful".

Sunday, March 29, 2009

A CLASSIC CAR RESTORATION : HONDA PRELUDE

The 2nd generation Honda Prelude (mfg. code "SBO") was an iconic symbol of mobility, sophistication, effluent, all back in the 80's. I was one of them who considered this as a "Dream Car" back then. I found this baby sitting at a used car dealer in 2002 with 300,000km. Specs. states that this is a 1.8 liter engine with twin carburettor, 12 valves, single cam, 4 wheel disc brakes & 4 wheel independent suspension with individually adjustable camber & castor angle. Compared with the sister Honda Accord, this is the "Ride" to kill for.

The first test drive was pure disappointment. The car was hesitating, pick-up was poor, steering out-of-alignment, sunroof not working ....... but the engine was smooth and goes willingly when rev-up - a typical feature with Honda engines that makes the marque so popular with the race-boys.




Among the items that are worn most in a 300k km car would be the engine. Suspension, brakes and steering would be the next on the list. The engine hoist is positioned for hoisting the engine & gearbox out. Balancing the engine-gearbox weight is very important to prevent tilting during the lift, which will damage other ancillaries if the weight centering is not properly managed



Shown here is the engine being hoisted out with the gearbox attached. This complete overhaul was done in 2005, after a prior cylinder head rebuilt that has failed to produced any results on excessive engine oil consumption, which was due to worn piston rings & pistons.




After the powertrain is hoisted out, the engine bay is cleaned and hand-painted with special anti-rust with matching color. Since there was no hurry, I took my own sweet time to tackle all the nook and corners.





This was how the cylinder head looks like after 3 years of usage. Cyl #2 & #4 appears to have excessive oil, indicating worn piston or rings. Cylinder block boring is definitely on the menu.






The pistons appeared to mirror the diagnosis, with heavy contamination of carbon deposits.







After the cyl block boring, the block is flushed cleaned thoroughly. This is important as the boring generates lots of metal chips and dusts. The block is painted RED, my favorite engine color.






After the assembly is completed, both the engine and g'box is hoisted back into the body as one.







Here it is, sitting right and pretty in the newly painted powertrain compartment. The subframe has been painted yellow to differentiate from the chasis color. This is to help in future maintenance. Bright colors make the dirt, oil stains show up well.






Hi Dad ! When can I go for a ride in the hot-rod ??








CYLINDER HEAD WORKS : Feb 2009
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In 2009, I had some spare time at hand and decided to rebuilt the cyl head due to overheating problem when doing high speed cruise (~140 km/h). My first check was on cyl bore wear, which appeared to be minimal with no indentions on the walls.





The photo shows the cyl head with about 3 years of usage, or 35,000km since the last rebuilt. Engine oil consumption (leakage) appeared to be under control this round with minimal carbon deposits.





Due to carefull selection of petrol pump stations, the intake valve sides appeared to be "clean" as advertised by company "P" and "E". #2 chamber was wet due to earlier direct oil injections during a compression check prior to cyl head removal. The compression reading was 210psi with no change when engine oil when injected.




The cyl head is then sent for surfacing at a local machine shop, with valve seats cut at the standard 30-45-60 degrees angle, with intake at 1.0mm, exhaust at 1.5mm valve seat widths.






I used the standard pencil test to confirm 100% full surface contact for the valve to valve-seat. In this test, a yellow marker was used against a grey (intake valve seat) background.








Here's a closed look, on the exhaust valve.







Yes, a grinding stick with paste is used to ensure a proper surface texture and to verify is the machine shop seat grinding is 100% aligned.







The cyl head, all prep up and ready to be mated to the block.







The block, with all pistons and surface cleaned up very meticulously, and new gasket installed.








The engine after mating the cyl head and block, with intake manifold attached, minus the twin carburettors.








This is all sooooo boring. Just leave me alone for a nap.




Friday, March 27, 2009

WHAT THIS BLOG IS ALL ABOUT

This blog is dedicated to car DIY's, who spends untold time, energy, and of course - $$$, to find the pleasure of building a ride, knowing the right thing has been done "under the hood".

For the other world of car owners, who cannot tell which way to turn a nut, this blog is meant as an information sharing. No offense please !

Finally, to promote my friendly home-service autoworkshop at Simpang Ampat, Penang.


My Fast & Furious workshop,
working overtime into the night.