sillbeer

I just wanted to share. Im doing the belts and rollers on my 83. I had noticed a while back that the a/c and alt pulley wobbles as it spins. So, I get under the car and take the starter off. Then im looking for this 5mm machined groove in flywheel for the alignment at the bottom of the bellhousing. it's not there. I find the thin line and the OT so I have to go with that. My clutch and flywheel says sachs on them. was sachs OE equipment? or have they been replaced? the flywheel lock didnt fit either. the teeth fit, but the bolt holes dont line up. the lock would only allow one bolt, but not both at the same time. so, i just locked the flywheel and tightened down the one bolt. I get the power steering pulley off and Im taking the alt pulley off. I ended up snapping two of the 4 bolts in the balance belt gear on the crank. uuuggghhhh. $47 from pelican....geez..I can only hope the rest of the job goes this smooth Not to mention, its 100 degrees at 1am when im doing this! good ole phoenix! //end rant

hpservertech

Feel your pain man! Just finishing up mine. Luckily I have a garage with a decent fan. But I almost have the wife convenced to let me get an AC for the garage. lol

sillbeer

UPDATE// I got the new balance belt gear. WOW. its a hefty piece. Its different from the one I took off. this one has 8 points for the pulley, not just 4 like the origional. also, these arent blind holes: they go all the way through. Anyhow, I got the belts on, I rotated the engine twice, then backed it up 1.5 teeth and checked the tension. The cam belt seems pretty easy, but the balance belt seems tight, even though I checked it with the krikit like 4 times. the cam belt is sitting at 4.0, and the balance belt is about 3.5-4.0 or so. the old balance belt was loose enough to the point that it was hitting the water pump roller! is there a way to know if they are too tight? will they whine? this is my first belt job on the porsche and I dont want to scew it up. I did the belts on my prelude but all you had to do was change the belt and release the tension on the tensioner and you dont have to worry about it for another 110,000 miles lol.

1986951

A quick check for your Balance Shaft Belt Tension...
Take the Belt midway in the longest "run" of the belt, and attempt to turn it 90 degrees...with two fingers!
If it will turn a little less than 90 degrees, the tension is about right... if it turns more than 90, too loose.
Then check it against Porsche specs via the "Gauge"... you will be amazed at how close this is!
Yes, it will "whine" if too tight, but that is not a good way to find out it's too tight!!!

sillbeer

thanks for the reply! I'll check that today when I get back to it. I could rotate both by hand 90 degrees, but I remember the cam belt being a bit harder to turn than the balance belt.

sillbeer

OK,I cranked up the car and man was it whining!! It subsided a little bit after a couple of minutes but it was still pretty bad. I think it was the balance belt thats too tight. I guess I'll just back it off a bit then re check the tension? I let the car run for about 10 minutes and it was loud as ****

FRporscheman

The 'book' says to put the BS belt at 27 lbs tension. But that always makes it whine! I put my BS belts at around 20 lbs and they hardly whine. Sometimes I don't even check the tension, and just leave the belt where it is still slightly flappy but mostly slack-free. If that belt ever snaps, it's no big deal anyway. about 10k miles on our 944 with a low-tension BS belt. About 3k miles on my 968 with the same low-tension on the BS belt.

sillbeer

thanks FR! Im gonna back it off in a few minutes...I gotta let it cool off. Its already hot enough outside. weather channel says 95 degrees but "feels like 91" lol gotta love az!

sillbeer

Right on...I loosened the TB and BB up a little bit. Now the BB was as loose as the old one was! I thought the old one was too loose! Before the belt change, I remembered a very slight whine at idle, which was barely audible unless the hood was up. Now it sounds the same as before. Maybe the next time I check the tension I can have Jeremy Himsel take a look at it with me. Im sure he has TONS more experience than I do on these.

Yabo

Err.. How I did it, and how I've alwasy heard it recommended before was, 90 degree twist on timing, and 180 degree twist on balance (EDIT- Checked clarks and it looks like balance and tension should both be same tension). balance belt should be much looser than timing belt.

Also another piece of information in this thread is incorrect. If the balance belt ever falls off or snaps, you are likely screwed. It has a very good possibility of catching in your timing belt somehwere, pulling it through one of it's pullies and snapping or throwing your timing belt.

Good luck.

PS: www.clarks-garage.com has the procedure for hand tensioning, as well as porsche tool tensioning, and the kricket too I believe. They also have all the tension specs.

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