10-08-08, 04:45 PM
I was trying to see if anyone has had a whine noise coming from behind the balancer area it seems.
I have taken the serp belt off and the noise is still there--so i tried to rule out any accessories.
Any help would be appreciated before I start taking the engine apart.
10-08-08, 05:35 PM
If the engine is running and the drive belt is in place, open the oil fill and stick a stethoscope tube or a piece of 5/8" fuel hose in a couple of inches and listen. Is the whine actually chain noise? The engine is DOHC, chain drive, so there is always some whine in the chaincase (right behind the harmonic balancer and accessory drive area. If you listened with the belt off it has to be the cam drives. 3 chains with hydraulic slippers and adjusters. If the whine is really noticeable, as in: 10 feet from the car, something's going wrong in there......
Remember the old cam gear drive trick which replaced the roller chain and made a standard OHV engine sound like a chain drive Ferrari ? Whine like that ??
Sub, could this be another manifold pressure relief valve? Seems to be a rash of them all of a sudden.
10-08-08, 08:09 PM
I thought of that and considered that he said "near the balancer" so I headed for the chaincase.
According to my '02 FSM the pressure relief is a removable affair in the TB end of the manifold, sort of a spring-loaded mushroom. BUT in a '99 I believe it's in the accessory drive end of the manifold, a spring-loaded swing gate, so he could have a persistent whistle there, too.
Back to the ol' stethoscope and search procedure.
.........and that's also where the oil pump is.....behind the balancer.
REALLY! I didn't realize that it was changed. I'll have to have a gander at my FSM's.
04-28-09, 05:49 PM
Restoman, did you ever find out what was causing the whining noise. I have a 1994 STS and it sounds like I have the same whine, been trying to pinpoint it for a couple of weeks now. It's in the fornt of the motor and remains steady when I take the tension off the serpentine belt causing all of the moving parts to stop turning. I'm quite sure that it is not the power steering although it sounds like a bad power steering pump but not nearly as loud.
Anyone with any suggestions would be appreciated!
04-29-09, 08:00 AM
I don't think we ever got to the bottom of this one - look at the date of the last post in '08.
IF the noise still persists with all accessories stopped, my bet is on a timing chain tensioner or slipper. If one of these, made of nylon, is coming apart there will be tiny yellow-white plastic chips in the oil filter and oil pan. Drive the car on the highway to really stir up and heat the oil........get it up on a lift and drain the oil into a large dishpan. Carefully cut the tapping plate off the filter can and disassemble the media, squeezing sections of the accordion dry in a vise. Open the pleats to see what's trapped there (discount any saw chips near the cut end.....). Carefully pour off the used oil and see what's settled to the bottom of the dishpan.
BTW, my description of the overpressure valve mushroom on the later FWD Northstar is incorrect: The mushroom valve IS in the accessory drive end of the intake; it inserts from the TB end........