S54 timing chain guide

[Pklauser]

New BMW engines (like the N20) have plastic timing chain guides which wear and fail. The S54 has cast aluminum guides with a plastic liner. The only parts that go bad are the upper guide and the oil pump chain tensioner.

I recommend taking a look at the thread I linked. Only one of the guides is aluminum, and that plastic liner isn't immortal, a couple of us have had problems with it failing. Both guides on the exhaust-side are completely plastic, granted I haven't heard reports of the lower exhaust guide failing.

[bigjae46]

New BMW engines (like the N20) have plastic timing chain guides which wear and fail. The S54 has cast aluminum guides with a plastic liner. The only parts that go bad are the upper guide and the oil pump chain tensioner.

[Ajcanadian]

Thanks all. Ended up ordered new guides, oil pump tensioner, timing cover gasket, and INA chain tensioner and a few hardware.

[Ajcanadian]

Some good info about replacing this stuff starting on page two of my thread here: https://nam3forum.com/forums/forum/m...ressions/page2

Also features two helpful members that have already chimed in here!

Thank you! That thread helped me out.

[Pklauser]

Some good info about replacing this stuff starting on page two of my thread here: https://nam3forum.com/forums/forum/m...ressions/page2

Also features two helpful members that have already chimed in here!

[cobra]

Exactly, it won't hurt it if I have the engine out. How many miles are on your engine?

100k

[Ajcanadian]

I just had mine apart and didn't replace the two side ones cause they looked perfectly fine. But yeah... plastic degrades so not a bad idea if you're doing a refresh.

I got the timing cover off and resealed without too much hassle. It would be very easy without the engine in the car. I just cleaned it super well to remove all trace amounts of oil and then put silicone sealant between the gasket layers and especially in the corner where the front cover mates with the block and head. It has only been 1500 miles but no leaks so far at all. The hard part was reinstalling the front main seal and had to make a tool to do it properly.

Exactly, it won't hurt it if I have the engine out. How many miles are on your engine?

[cobra]

Exactly, at that point why not do all new guides and chains and such.

I just had mine apart and didn't replace the two side ones cause they looked perfectly fine. But yeah... plastic degrades so not a bad idea if you're doing a refresh.

I got the timing cover off and resealed without too much hassle. It would be very easy without the engine in the car. I just cleaned it super well to remove all trace amounts of oil and then put silicone sealant between the gasket layers and especially in the corner where the front cover mates with the block and head. It has only been 1500 miles but no leaks so far at all. The hard part was reinstalling the front main seal and had to make a tool to do it properly.

[Ajcanadian]

Only problem with replacing the oil pump tensioner is that the timing cover has to come off. Which technically means that the head needs to come off. Plenty of people have removed and reinstalled just the timing cover (including myself), but technically you are supposed to remove the head.

If you're going to be doing all that, it's probably worth spending the $50 to have fresh guides.

Exactly, at that point why not do all new guides and chains and such.

[heinzboehmer]

Only problem with replacing the oil pump tensioner is that the timing cover has to come off. Which technically means that the head needs to come off. Plenty of people have removed and reinstalled just the timing cover (including myself), but technically you are supposed to remove the head.

If you're going to be doing all that, it's probably worth spending the $50 to have fresh guides.

[Ajcanadian]

I would certainly replace the oil pump tensioner. Mine was so brittle it cracked in half while doing the rod bearings.

The other chain guides seem to last quite long. The right side one is aluminum with a plastic cover, and the left side one is fiber reinforced plastic.

I will certainly order that and replace it while I’m in there. Thank you that was the information I’m looking for. At that rate, I’ll leave the other timing chain guides alone. I’ll just change the front crank seal

[cobra]

I would certainly replace the oil pump tensioner. Mine was so brittle it cracked in half while doing the rod bearings.

The other chain guides seem to last quite long. The right side one is aluminum with a plastic cover, and the left side one is fiber reinforced plastic.

[heinzboehmer]

Yeah the timing chain guides themselves don't seem to fail often at all on this engine. But make sure you at least check the bolt that goes through the head and holds the top part of the driver's side guide. Those tend to back out and can cause a lot of issues if they're loose.

[Ajcanadian]

I don't think timing chain issues are of major concern on this vehicle not to mention to replace one you must pull the head. I guess there is a way to do it without pulling the head but some don't recommend that.

I would only be doing the chain at the point the head was comming off, thats my .02. But definitely do the vanos stuff, or at least get a visual on your pump driver tangs and cam sleeve bolts.

Congrats on the purchase!

Yeah, I got the Vanos parts from beisans so I was going to do it all. I didn’t get the Vanos tabs since I don’t have any codes yet. I also got the upgraded bolts from Lang racing and the rouge engineering Vanos oil line and their cpv o ring. My thoughts were. If the engine is coming out and I’m doing the crank seal. Why not pull the cover and do the chains? I know timing chain guides other than the top piece by the Vanos unit is a common failure point but wasn’t sure if the other parts failed like the S62s and M62Tus cause they are 21 year old plastics.

[oceansize]

What he said ^