4Driver4

Anyone been in this far? Tips for changing chains and resetting timing?

Need to replace a few bank one valves too....oddly, it's bent intake valves.

(Not my car BTW. Doing a favor for a friend.)

4Driver4

Wider shot showing the fancy trans bracket I welded up for the trans jack.

KevinGary

How did you flip the car upside down? Lol

4Driver4

It's levitating. ;-)

KevinGary

The dealer has my 4.2 for the chains right now. I am hoping that it is only the guides or the tensioners. I am sure the bill is going to be large. Just hoping that the chains are ok.

Mike141

What was the problem the owner was having, and how many miles on it?

4Driver4

I'm going to do all the chains and guides. Once you get this far, you may as well.

Car was noisy and ran poorly. Bank one cams were in time with each other, but out of time with everything else. Still need to pull the bank one head. Cylinder 1 fails leakdown.

SchwarzS6

Did you identify any failed parts in the chain guides or tensioners?

4Driver4

Nothing obvious yet. The only thing I see is that the main chain tensioner piston retracts very easily. I need to get the oil pump chain off first, but my Bentley PC crashed and I'm not digging deeper without support.

Have I mentioned lately how much I hate Bentley Publishers? They tell you that you should only install on PC's that are stable so you don't risk content loss...but the newest operating system they support goes end of life in a week. Fan-f'ing-tastic.

ProtoFly

Kevin, when I see that your car also has the problem, I absolutely know that this is a failure in design, not maintenance.

What were the symptoms that made you take it to the dealer?

I finally have all the parts I need to complete mine, and was working on it this weekend. I have about $2000 in parts, including head gaskets, plus my labor. Sent the heads out for resurfacing, etc, new valve seals.

I'm hoping I'm good for another 175k miles, though.

Some of the parts have been redesigned or improved.

For what its worth, although I opted to replace the two upper chains, there was no evidence of stretching. It is the guides which fail, and sometimes the cam adjuster mechanisms.

Based on my non-scientific observation, the passenger side cam chain tensioner seems to be a weak point, as it sheds its plastic, ejecting it into the chain cog. I've noted at least 5 failures on various forums of that.

There will also be a cracked/broken lower guide, but that, I think, only causes the cold start 'rattle'.

Next is the adjusters, which have a locking pin, and the hole that the locking pin goes into gets elongated and then fails to lock.