: Would these chain tensioners cause excessive engine noise?

03-10-13, 08:22 PM
Hey all. I got my hands on a 97 Eldorado from the in-laws and they had parked it about 6 years ago because there was a whirring or whining noise coming from the engine. My father in-law was pretty sure that the chain tensioners were the problem. So I popped the timing cover off and pulled them for inspection. There is obvious wear on them and I will replace them regardless. I'm just wondering if this type of wear pattern would cause the described noise. Since I never actually ran the engine before pulling the timing cover I have no idea what sound pops was talking about. But I do trust his judgement in the engine department. I just wanted an extra couple of opinions before I button it all back up.

The chains and gears look incredible inside. They are so clean and new looking that its amazing that they have seen use. No unusual wear on the teeth or hot spots on the chain. For all the negative I have heard about the Northstar, I'm very impressed at the engineering behind it.

That being said, since I have it apart this far and she hasn't run in at least 6 years, is there anything else I should replace besides the tensioner shoes and the timing cover gasket and seal? Oil pump maybe?

Thanks all for any and all your help.



Same tensioner but notice the diagonal wear pattern

Shown in poor detail are the other two. The one at the top looks like the chain was really hitting the face of it. (more noise source?)

Manic Mechanic
03-11-13, 01:15 PM
My opinion is yes those look like noise makers. And other than those there's nothing internal engine other than those to cause a whirring noise. Once you get it running if the noise is still there I'll bet you it's on the belt drive and therefore external.

Time to stud or insert the block. You'll greatly regret it if you don't, no bull. Timing chain removal an install is about one third of the battle for the job.


03-11-13, 01:40 PM
Hey Vernon thanks for the reply. I asked pops again about the specifics of the noises and he added that the engine sounded a little "clanky" on startup and for about 30 seconds along with the whirring noise at all times. He thought that the tensioners were taking time to get to full pressure on initial startup which was causing the additional sound.

It sort of makes sense since I was able to remove the crank pulley nut without locking the flywheel using only an impact gun. I thought for sure it was going to be waaaaay harder for it to come off. That might make the oil pump not spin at the correct rate causing a drop in pressure. He said the oil light or any other code never popped up that he can remember.

Well, off to NAPA or wherever else to find the parts I need. I need to price out the cost of doing the inserts. Money is always a huge factor.

Thanks again, NAES

03-12-13, 01:32 PM
Hey all, I need to swap in new timing chain tensioners and notice there are a couple of options. I'm not in the loop as to quality of parts so I was hoping you all would chime in.

Rock auto has Cloyes and Melling as options. I have Cloyes in my Chrysler engine and am very happy with them. But I have a blueprinted Melling oil pump in my VW. I know I'm comparing apples to oranges but I plan on doing this job once in my life and want to buy the right stuff.

Thanks, NAES

03-12-13, 04:21 PM
Either is just fine. Threads on the same subject merged.

(I use both Cloyes and Melling in several types of big-block overhauls and have never had a problem with their products.)

03-12-13, 05:48 PM
Great, thanks for the quick reply.

My apologies for clogging the board with excess related posts.


03-13-13, 06:04 AM
Not a problem - that's what makes this site fun - digging through the gray matter for car stuff !

(You think you have chain whine - you should hear the cam chain drives in some of the older 3 liter Ferrari V-12 DOHC engines at 9,000 rpm !!!)

Mark D
03-13-13, 05:10 PM
In viewing the photo's, those tensioners don't look any worse, not even as bad, as some that I've replaced even though they weren't making noise.
Yes, if it were I and I had the timing cover off, and if I expected the engine to run a lot more miles, I'd replace them anyway.
But I'd bet the noise is not coming from the tensioners. External noise probably. Power steering pump comes to mind. Also worn bearings on one of the belt tensioners (water pump or accy. drive belt)
Also, alternators can do that, especially when they have a shorted winding. But that's more of a whine.
Transmission pump can do it too. That's worst case scenario in my view.
Mark D.

03-14-13, 10:43 AM
Motor is in car? How are u locking flywheel to install balancer bolt?

03-14-13, 05:37 PM
Two or three ways - use the GM flywheel lock tool in place of the starter motor or lock the ring gear with jury-rig inside the lower transmission case inspection cover.

Manic Mechanic
03-15-13, 02:35 PM
I see the one Sub mentioned on EbayMotors also but the one I have (KENTMOORE TOOL J-39411 4.6L NORTHSTAR 4.0L ENGINE FLYWHEEL HOLDER) goes on from underneath at the inspection cover area. Works well and no starter removal required. Before I obtained one I have used the tip of a large pry-bar in-between two flywheel teeth from underneath. You may need a helper to hold it.


03-15-13, 03:00 PM