Has anyone replaced the chain guides on an N62?

[Bulk]

That's a shit load of gaskets. I might just get the gasket goo in a tube!

[pezho405]

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[swissfrank]

Originally Posted by pezho405

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Wow, the same yet so different! I can't wait to pick up a n62 as my next project, but I am actually holding out from a s62 if anyone see one

[Bulk]

Originally Posted by pezho405

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Top right hand corner - a mini X in the engine bay. Hahaha

[pezho405]

Originally Posted by Bulk

Top right hand corner - a mini X in the engine bay. Hahaha

Yup sure is!

[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

[pezho405]

Originally Posted by carl0s

That picture tells you something important.

....

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

Thanks for the great info! and welcome!

[TwinTurboGTR]

I agree with Duke on things to replace... But wrong motor. Both of Duke's motors are the M62 config. But the principles are pretty much the same. Just not sure if you can use the M62 cam locking tools on a N62 motor.

[williamx5]

Good day!!

I had a thread with my 2004 N62 rebuild on here with pictures, but photobucket destroyed that when they got rid of free hosting...

I'll see if I can put some on here directly for you... I also try to do a write up on it in the near future...

From my pictures, you MIGHT be able to do the guides with the heads installed... The lower cover has bolts that go thru a casting for the cylinder head, but they aren't the main head bolts used to hold compression. I took the chain cover off the front of the block with the heads on to seal the water passage better. I'll do a little detailed posting here with pictures in a second... I have to upload them and attach them...

Here is a shot (upside down) of the new guides with chains... Three have bolts that hold them on... There is also one that doesn't make things easy...

****I just remembered about the alternator mounting bracket... It extends around the front of the lower timing guide and down the side of the motor... That needs to be removed in order to get the front cover off... The front diff needs to be removed to get to the lower rear bolt holding that bracket on the block...*****





Here is a bad shot of the lower guide removed with the heads installed... You might be able to get the three guides out, but the last one needs to come straight out from the block... I think it will hit the head casting before it clears the pin...



If you pull the vanos units off, you can get access to the chain easily... You don't have to loosen the cam caps like I have done here for the exhaust side... That bolt on the lower area of the head is holding the top of the guide in place...



Here is the bolt that holds the guide on...



So, it would be best to remove the heads, but I personally don't think it is a requirement... The oil pans need to be loose to get the front cover in without damaging the gasket...

Let me know if you need more pictures of something specific... I'll post them up...

Cheers!!

[kavala]

what about the timing chain ???

My mechanic says he cannot fit the new timing chain without removing the cylinder heads ???

(BTW - many thanks for taking the time to post the images. Very helpful)