[theoneandonlyjeff]

I have what I consider a strange problem with my 2005 Deville engiine with 125k miles on it.

I pulled in the garage and shut the car off. An hour later, I started the car and hear a VERY nasty VERY loud clacking sound. I shut it off immediately. I asked a mechanic friend to look at it. He started the car, heard the noise and shut it off immediately.

He opened the hood, unscrewed the oil cap and pulled out 2 small green plastic pieces and told me that the cam chain guide/tensioner broke. He also said it will be very expensive to repair.

If you've followed along this long, thank you.

I searched this forum and others to try to determine what part(s) in the engine were green. I couldn't find green plastic parts in any engine photo I could find. That's the strange part.

What part(s) are green plastic? I was told by many people that the Northstar engines were bullet proof.

Was my friend's diagnostic correct?

I used to blueprint 426 Hemi engines when I was younger, but I don't think I'm up to doing something this complicated. Any help/suggestions are appreciated.

 

[Submariner409]

Sounds like a timing chain tensioner shoe or a guide slipper has disintegrated. Rebuild can be done through the wheelwell with everything moved out of the way. Not easy. Many special procedures. Given the nasty noises, one or more timing chains may be damaged, too.

You will NEED a subscription to www.alldatadiy.com - the online GM Cadillac factory service manuals. Too many timing tricks and correct assembly/torque procedures needed to wing it.

www.rockauto.com - make, model, year, engine, timing chain guide/tensioner

Note the amber and light green nylon parts ............colors vary depending on manufacturer or OEM contract parts source.

 

[Ranger]

What part(s) are green plastic?

:noidea:

Those chain tensioner shoes "SHOULD" outlast the engine.
Never saw a picture of a green one until I just goolged this.
I don't think it is OEM though. Could yours have been replaced earlier?

 

[Ranger]

What part(s) are green plastic?

:noidea:

Those chain tensioner shoes "SHOULD" outlast the engine.
Never saw a picture of a green one until I just goolged this.
I don't think it is OEM though. Could yours have been replaced earlier?

EDIT:
Picture won't post.
Click this link and see the 3rd picture.
https://www.google.com/search?q=nor...UIDygC&biw=1440&bih=736#imgrc=srjqnCG4rAfUmM:

 

[Submariner409]

AC Delco timing chain (primary) tensioner. 2005 engine.

The little green spike thingy is the tensioner piston lock pin that gets pulled after install.

See the tiny hole in the oval recess? That's the engine oil pressure port to the tensioner slipper piston.

 

[RON93]

This is the guy who did the head bolts on my 2000 Deville.

 

[Ranger]

Well, I guess we know where the green plastic came from.

 

[theoneandonlyjeff]

Thanks to all your replies. I REALLY appreciate them. I guess I'll bite the bullet and have a certified Northstar mechanic repair it. I'm getting too old to be doing these kinds of extensive repairs. I've gotten a few quotes around $2.5k. It's been a good car so far and if this buys me another 8 years, it will be worth it.
I've been toying with the idea of parting it out and just buy another vehicle. I don't think it's worth much in it's present condition so selling it is probably out of the question.

Any thoughts or comments on what you'd do if you were in my shoes? I'm not rich, I'm retired, living on a fixed income.

 

[Submariner409]

The labor times for replacing those guides/tensioners is about 4 hours - assuming the suspension and fender liner is removed previously. So 8 hours isn't too far off. $800 alone if labor is $100 an hour. The actual parts aren't too expensive (Maybe $250) so $2500 sounds a bit high. All 3 chains would add another $100 or so.

A 2005 in otherwise good condition is worth the repair, though. I'd fix it.