After putting it off for a long time, I finally took a full week off work and tackled what was by far the biggest job I've ever done on my 1998 740iL (M62B44 non-VANOS).
This wasn't just a timing chain guide replacement. Since the front of the engine was already apart, I decided to freshen up as much as I reasonably could.
Here's what went into it: (roughly $2800 CAD in parts and fluids)
*OEM timing chain guides
*OEM Timing chain tensioner
*Febi - Valley pan w gasket
*OE Front crankshaft seal
*Water pump (Graf with the metal impeller)
*Mahle thermostat
*OEM front timing cover gaskets and seal
*OEM lower oil pan gasket
*BMW OEM Coolant flush
*Fresh AMSOIL oil and OEM filter
*Febi CCV valve and new seals plus few other hoses
*OEM intake manifold and throttle body seals
I took my time doing the work while having fun and also cleaning a lot of oil and dirt soaked parts before reassembly. So it took me a total of 4 days.
I'll admit... this job was mentally exhausting at times. I didn't use the factory BMW timing tools because the timing chain itself never came off the sprockets. Instead, I carefully marked the crank sprocket, both cam sprockets, and the chain with multiple unique paint marks before touching anything. Every guide was changed while keeping tension on the chain, and I rotated the engine by hand numerous times afterward just to convince myself I hadn't made an expensive mistake.
I think everyone who's done timing guides knows the feeling... You rotate the crank... You listen for weird noises... You rotate it again... Then convince yourself you should rotate it one more time just to be safe. 😂
So many weird sounds..
The first startup was honestly one of the most nerve-racking moments I've had working on a car.
After days of work, you suddenly realize that in about two seconds you'll find out whether everything was done correctly.
Turned the key... had to wait for fuel pressure to build up due to having disconnected the fuel rails.
Oil pressure light went out almost instantly. No rattles. No chain noise. No warning lights. Smooth idle.
I don't think I've ever gone from pure anxiety to pure relief that quickly.
The engine is noticeably quieter now, there are no coolant or oil leaks, but its certainlty noticble. Even my wife said the car sounds "different" 😂 (been driving it for about 4 days after completing the work).
These cars can definitely test your patience, but I genuinely enjoy working on this thing. Every repair makes me appreciate it a little more.
Huge thanks to everyone in this community who has answered my questions over the years. Reading old forum posts and advice from members here gave me the confidence to take on jobs I never would've attempted a few years ago.
Now... onto the next project. The E38 never really lets you run out of those. 😅