dreaded whine from belts

[nynor]

as per my other post today, i did my timing and balance shaft belts. they were extremely loose. before changing anything, i used the 9201 tool to see what they were at. the timing belt was at 1 on the tool, the balance belt didn't even register on the dial.

afterwards, and i checked EVERYTHING three times when tensioning the belts, i have some whine from the belts. i'm not sure if i am being paranoid or what. i tensioned the timing belt to about 2.8 on the tool and the balance shaft belt to 3 on the tool.

i guess i am not really worried about it as the car is now parked until i can replace the head gasket and some other stuff. i'll get new belts as well. i think the rollers and the water pump only have 11K on them.

[Techno Duck]

Make sure the idler pulley for the balance shaft belt is indexed correctly, if it is touching the belt it will cause a whine. It should be roughly 1mm away from touching.

Also a balance shaft belt which is too tight will cause a whine. Overly tensioned timing belt tends to make a 'whiring' sound.

[Dougster]

When mine were done awhile back they did for over a month before going away...

[Eldorado]

mine did it for a few weeks after paul changed my belts.

[toolboy62]

Honestly, i've never heard a 944 that didn't have a belt whine.

nate

[EMBPilot]

nynor,
like the guys said, and i struggled with this too after a belt change. if *you* can hear it a little, i think thats normal, you just dont want a LOUD supercharger sounding WHINE thats really pronounced over the rest of the engine. mine was pretty loud, i readjusted it, after several emails and 8000 checks with Bruce's equipment and it reduced it about 95%. i can still hear it a tiny tiny bit but its because i know what to listen for.

i mentioned this on the thread i did about my belt whine, when tensioned correctly, the BB will seem freakishly loose. Mine had almost a half inch of deflection on it across the largest span.

New Belts, New Whine

[nynor]

oh yeah, mine is totally loose. not like it was before re-tensioning, but pretty loose. i am thinking that was just nearly no whine before, but now that it has tension, there is a bit of whine.

[Tidybuoy]

I just had new belts put in by a Porsche shop. The mechanic told me that the belts would whine a bit (probably for about 500 miles). I still have to bring the car in for the 500 mile tensioning, which I'm doing this Thursday and I'll see if they whine after that.

Personally, I like the sound. It's got that Porsche sound (not exactly like a 911 but still sounds good).

Vern

[Porsche-O-Phile]

When installing new belts, prior to the 1500-mile retension, they will whine a bit. Even after the retension, they'll whine a little for a few weeks, then gradually it'll subside.

That's my experience anyway.

[mattdavis11]

I concur with the others. Belt some whine=good, no whine= possible trouble. Make sure you index the roller for the BB correctly.

Sorry to hear about the head gasket. I hope you don't have a broken stud, but if so I hope it comes out easy. Take your time, and good luck man.

[nynor]

well, i decided to trust myself a little and ran it till warm (see my other post for results of stud cleaning...). i decided it sounded fine. but the studs (the back one is doing it as well) are definitely bubbling coolant.

[Aufenbahn]

Not that I speak from any great amount of experiance - but isn't the ba lance belt supposed to be looser than the cam belt? In the first post it looks like the opposite - or is the higher number a looser condition? Just Wondering, Thanks

[nynor]

the setting for both the belts, when they are NOT new, is 3.0 +-.3.

when NEW, timing belt is 4.0 +-.3 and balance belt is the same as above.

[HondaDustR]

Originally posted by nynor
the setting for both the belts, when they are NOT new, is 3.0 +-.3.

when NEW, timing belt is 4.0 +-.3 and balance belt is the same as above.

According to clarks garage, a used timing belt should be 2.7 +/- .3, and the balance belt depends on which type you have.

Old style (15mm wide) 2.7 +/- .3
New style (18mm wide) 3.5 +/- .5

Although the numbers are the same (or higher for the new style) as the cam belt for BB tension, they are actually looser. Since the balance belt is thicker than the cam belt, it will push the tool lever harder for a given tension, giving a higher reading.

Before I borrowed the 9201, I made the mistake of assuming since the numbers are the same, the BB should feel the same as the cam belt. It sounded like a supercharger until I set it to the right tension.

[nynor]

after putting new rollers and belts on, no whine at all. none. the rollers were worn, not horrible, but sounded and felt like roller skate wheels when spun. i'll probably pull it all apart in a couple of weeks to see what is going on.

[Gremlin85]

how much would it cost to have a mechanic re-tension the belts? The PO did the belts and I don't have the tension tool......... niether did he.

:::EDIT::: My belt wine is very audible. I did'nt notice it until a week ago. I remember I never heard anything until that point. Prone to wine???

In your case, it seems its a normal occurance in the 944 from whats being said.

[Eldorado]

i took it to a porsche shop... they did it for 60cdn bucks cash... less than an hour's worth of labour.

[nynor]

if you have obvious/loud belt whine, i'd check the rollers and make sure they are not worn out.