Has anyone replaced the chain guides on an N62?

[carl0s]

That picture tells you something important.

The upper timing chain housing is now part of the cylinder head.

On the M62 it wasn't - you took away some bolts and then you could remove the front part of the cylinder head, and slide the chain guides forward.

I'm afraid on the N62, the right-hand side requires removal of the cylinder head in order to change the guides. I can't see any way around it anyway.

On the left hand side of the engine (opposite to the picture above), you can replace them easily, because the pivot bolts/bearings screw out from the front. On the problematic side, they screw out from behind the guide.

Here are some pictures:


Here you can see the part of the cylinder head that is not removable in the N62. This is supposedly an improvement over the M62. Not for the customer!!




Here you can see *behind* the right-side chain guides. This is where you have to unscrew the bearing bolts - the pivot points for the guides on this side. They can only be unscrewed *after* removing the guides, by sliding the guides forwards, which you can't do because of the cylinder head mentioned above.


Here is the same from the front. The guides need to slide forward off here:


Here you can see the other side of the engine - the left side (left side if we were sat in the seats of the car). On this side the pivot screws / bearing bolts actually just remove from the front easily, and then you can drop the guides down / manoeuvre them out no problem.



Last thing to share: in 2005 the chain guides were updated. They are now longer, and also on the left side - those that can actually be replaced fairly easily (presuming you already have the engine in bits to fix a leaky coolant pipe or alternator bracket oil seal), the pivot screw/bearing bolt is larger, so newer ones of those (those circled in the picture just above) are needed to go with the newer guides.

You have to replace the guides in pairs (top/bottom), and the older part is no longer available. If it were, you might be able to just pop the plastic bit out of the middle and at least replace that bit on the troublesome right side.

The Febi parts are actually OEM BMW parts, and they have ground-out the BMW logos and the words BMW off of them.

Here are some old-v-new pictures. This is the left-side upper (plastic) guide. The lower metal guide is also increased in size about the same amount.





Of course prior to all this, you have to remove the lower timing cover.
The secret to that, IMO, is to remove the lower oil pan, and just loosen the bolts to the upper oil pan a little. Then the timing cover will pop off easily. Cylinder heads can stay put. Alternator and A/C compressor need to be removed, because they are doweled into the side of the timing cover, or their brackets are (alternator bracket is, and a/c compressor itself is).

Cost me $0.25 to share all that with you! I don't even have an X