Wreckster

I bought a 944 over the summer and I love the car but the car has an annoying belt whine. The previous owner was a certified mechanic and he changed all the belts and such but I don't think he tensioned the belt correctly. I listened to some sound clips of over tighten belts and it sounds identical to my car. Now, I consider myself a some what competent mechanic, would I be able to crawl under the car and just loosen the lock nut on the belt tensioner, loosen the belt a bit and retighten the nut? I hear I need a flat 27mm wrench which I can get.

Or, is there anyone in New Jersey that could give me a hand with this one weekend? I'll provide a six-pack of your choice for the help.

AScholtes

It may not necessarily be over tightened. From what I understand some just whine (mine being one of them....) even when tensioned properly...

Yarf

Information you need to read and understand if you are going to do belt maintenance.
http://www.clarks-garage.com/pdf-manual/eng-10.pdf

Wreckster

I don't know, this car whines loud, I know that they cars have an engine whine but this is a bit over the top.

After reading that bit about tensioning the belt, seems a bit out of my element, I don't have a tensioning tool.

AScholtes

search "twist method" and see what you come up with... Also, check YouTube for some videos on the procedure that Van (a member here) produced and uploaded.

bonus12

Yeah, use the 180 degree twist method. Easier than it sounds. For a video:

It may not be that easy if you need to remove the front timing belt cover...and to do that you need to remove the power steering and alternator + a/c belts. It is still easy to detension these belts and remove them, and possibly retension them too. Unless you can just kind of lift the front timing belt cover and reach the tensioner nut with the tools?

xsboost90

ive had them whine when they were too loose. Usually means you need rollers. Sometimes you can loosen and it works. I usually over tighten just alittle and let the belt stretch.

montel52

I would remove both alternator/ AC and power steering belts and see if the whine is still there. Power steering pumps can make a lot of noise when failing.

mytrplseven

Montel52 is right.
First you have to find out which of the 4 belts is whining. The alternator and power steering belts are easily removed to see if they are the problem. If they aren't then you have to pull the upper and lower front belt covers (about a dozen small bolts) to get access to the belts. You won't be able to tell if the rollers/idlers are bad without taking the belts off (or at least loosening the tension on them to the point you can spin them) and listen for a buzz when spinning. If they're ok then it's usually the balance belt and the adjustment I've found easiest and most trouble-free is adjusting the tension on the belt so you can twist the belt on the driver's side 90 degrees. Do you have any past maintenance records that'll show when they were changed last and if the idlers were done then too?

F40LM

Ditto, all I used was Clarks, vans videos, and the shop manual. These three sources will see you through.

St3mpy2

Check the balance shaft idler pulley. If its touching the belt it will whine, regardless of belt tension. It should be about 1mm away from the belt.

Wreckster

So I am going to dig into the belts tomorrow and try to see whats what. How many bolts does the belt cover have on it and is that all I need to remove if I want to work on the bottom of the engine? I questioned the previous owner and he said he never did belts on a 944 before, he said he just set the belts to what felt right for any car he's changed belts on. (He was an SAE certified mechanic). He also said that the car needed a new bearing down near where the tensioner is, so I really feel that the belts are just over tightened. As far as power steering, I have a leak in it so I have to top it off now and again but when the reservoir is full the power steering works great. I also listened to a video on a site where the guy said the belt was over tensioned and it sounded identical to my car.

mytrplseven

Here's my skinny on the belt issue: 10MM sockets with short (6" extension) for the upper and lower cover bolts. You never stated it your car is a later one with spring loaded tensioner for the timing belt or an early one. The timing belt should have the tensioner tight enough that you can grip the water pump hub and under some firm resistance, turn the hub. If too tight you won't be able to. Too loose and it will turn easy and cause the water pump to slip and might cause warmer engine temps. On the later ones with the spring tensioner, loosen the 2 lock bolts on the top of the tensioner and using a 17 mm wrench on the mounting nut as a lever, turn the whole tensioner to the point where you have the proper tension on the WP and the lock down the two lock bolts and after turning the engine a few revs (see note below), check the WP tension again to be sure. For the balance belt, the video shown above works perfect. Adjust the tensioner (bottom of the engine using one wrench for the concentric nut) (I used water pump pliers that were ground down a bit to make them thinner) and to the point where the balance belt will twist 90 degrees on the long up side on the right of the engine and lock it down with a 17mm wrench. The idler pulley should have clearance so there's a credit card clearance between the idler and the belt, it shouldn't touch. Turn the motor a gain (see notes below) a few revs and recheck. If your rollers and idlers in good condition and don't make any noise when you spin them then you're basically done. Recheck tensions after about 1500 to 2000 miles to see if they need tweeking after they've settled in. Mine have perormed perfectly using this method and checking the rollers, idlers found a couple that sounded like old steel strap-on roller skates of the early '50's. In all cases, before you turn the motor (recommend by using a deep 24 mm socket I think, on the crank bolt) a couple of turns clock-wise, re-verify the cam sprocket is at TDC and balance belt sprockets line up with index markers on the rear housing (see Clarks garage if you're not sure). They don't have to be spot on but very close. It's usually easiest with this with the spark plugs removed. Good luck with this.

Wreckster

Sorry, the car is an 87 NA

StoogeMoe

There's the problem. The belts are surprisingly loose compared to other vehicles.