[Ginricky]

Hello, I have an '05 Deville in otherwise very nice shape purchased for $300 with 177K miles. There is a steady, significant tick from the front lower right of the engine (passenger rear in vehicle) that is only noticeable at low idle. It is also louder for a second on startup. I work at an auto repair shop but am not familiar in any particular way with the Northstar. This car is mine and I'd like to save it if within reason to do so.

There is discoloration of the oil slowly accumulating after a fresh change. The front (left) chain and what I can see by removing the oil cap looks tight and fine. However, the noise becomes magnitudes louder once the oil cap is removed; sounds like a midget in there with a ball-peen hammer. No smoke from exhaust, no excessive oil consumption. I have put a camera in both sides of the cover and made an attempt to look around but can't identify anything specific, but upon pulling the plastic plug from the passenger rear top of the timing cover I found a grey oil paste that had accumulated in the threads.

Everything suggests to me that this is a timing issue, and that the only way to be positive is to pull the cover. I cannot seem to find anywhere information/video, etc, in regards to doing this in a transverse mounted FWD. I presume the dealer simply drops the entire unit out with the subframe, though there is a bit more room in the car to do the job once the accessories are removed than I would have expected. Question is; do you think I am on the right track with my diagnosis, and if so, is it viable to do without dropping everything out the bottom?

Thanks,

Emerson

 

[Submariner409]

Welcome to the Funny Farm !!!

At 177K I'd guess that the chain tensioners and guide slippers are worn down - the right (rear) bank or crank chain tensioner would account for the click/whine noise.

IF the nylon/teflon tensioner slipper - on any tensioner - is worn out I'd really check the chain rollers for wear. Otherwise, the chains are pretty tough and good for a LONG time.

You can get to the timing cover with the engine/powertrain in the car but it's tight work. Car up on jackstands - wheel, disc, fender liner, stuff out of the way. To unbolt the balancer bolt you must lock the engine flexplate - either by removing the intake manifold and starter and using a (hideously expensive) GM lock tool or maybe by jamming the flexplate gear by removing the inspection plate at the bottom of the "bellhousing" area. Special technique of torque + additional degrees of twist to replace the balancer.

Subscribe the car to www.alldatadiy.com - the online GM/Cadillac service manuals. Too many special procedures and torques to type out here.

Here are a few looks at what you're up against ........ click to enlarge, use the prompts at the bottom of each picture.

 

[Ginricky]

Thanks for the comprehensive response; I strongly suspect the Primary tensioner at the crank, sight unseen. Noises can of course be difficult to narrow down but this one comes very strongly from right about that spot; it also appears from the pictures that it would be the most likely to fail first. Small shoe and quite a bit of tension action there. Alldata shows GM's four tooth "Flywheel Holder" with a single bolt to hold it in the block.

I'll probably tear into it and make a multi day project out of the deal; I'm a service writer, not an active tech and my lower back has never been right since my early days at a marine high performance engine shop. I'm fine for any work...until I bend over the hood of a car and the brutality starts quickly working me over.

 

[rodnok01]

Flywheel holders cheap enough on ebay used, think i paid 10 bucks and worth every penny(iirc there's 2 different models).
My 98 tensioners were worn almost to steel at 100k.

 

[Submariner409]

Yeah - if you look real hard at the pic of the crank snout and intermediate chain sprocket you'll see the chain tensioner slipper is worn down to the metal backing shoe - it ate the primary chain.

I'm a service writer, not an active tech and my lower back has never been right since my early days at a marine high performance engine shop.

Heh, heh ..........Up until arthritis took over one of my "hobbies" (for fun and profit) was building Olds 455 and GM 454 marine engines, from low-rpm high-torque stump pullers for workboats to fully tricked out Mercruiser I/O powerhouses.

One of my Olds 455s, bored to 461, workhorse engine - Milodon 8 quart marine pan, Mondello ported heads, Comp roller tips, other tricks. Second pic is another 455 build in our 38' BayBuilt workboat that we turned into a cruiser.

 

[Ranger]

sounds like a midget in there with a ball-peen hammer.

Take away the hammer.

Sorry, to good to resist. The devil made me do it. :lildevil:

 

[Ginricky]

I'd honestly rather pay someone else to take away the hammer, but I'll probably end up doing it myself.

 

[rodnok01]

I'd rather tear the frt apart than do crossover gaskets myself. Think your back hurts.. Do those and it will for sure.