Fan Belt 1978 911sc

[Wew]

Hey all,

It's me again happily working away on my project today. I clean up the fan and shroud, reconnected everything and put a new belt on the fan to camshaft housing... I believe. The outer part is for the A/C which I still havent hooked up.
My question is how tight is this belt supposed to be. I have moved a washer from inside of the housing to the outer part in hopes of tightening up the loose belt. It just seems to pull the whole mechanism forward.
Also when I tight the 24mm nut and turn, the belt just slips on the cam shaft and does not turn... Is this normal or am I missing something.
With the additional washers it certainly is not a straight line up and down when looking at it from above and the upper portion is out more, which I was thinking was necessary to tighten the belt tension. Anyway attached are some images is anyone has any tips or steps I may have missed.
Thanks again,

Gary

[timmy2]

Your belt is in the wrong pulley. It goes between the fan sheave and the removeable pulley sheave. (Move it in)
You are on the Air pump pulley groove.
You need to put the belt between the fan and the removeable part as you juggle the washers and spacer and nut, then tighten.

[Bob Kontak]

[Wew]

You guys are awesome and I am a knucklehead. Thanks a bunch.

Gary

[maui44]

The torque on the 24mm should be 29.48 Ft-Lbs

[Wew]

29.84 it shall be. I also removed 3 of the spark plugs on the drivers side and made sure it was in neutral. Got the belt in the right spot and still just slips. I.e. won't spin the crank shaft. I guess I will have to remove the other three plugs. Other than that I will jut have to crank it with battery. Any words of wisdom prior is appreciated.

[James Brown]

wait, stop, don't do anything, don't start it. You say "the whole housing moves forward" do you mean the whole fan housing moves forward? that should not move IF you have the fan strap tight. Damage may result if you start. The belt is driven off the crank to the fan. you have the spanner and the 24mm socket? Start with 2 washers on the fan shaft (after ensuring the fan housing is correctly installed and tight) the rest of the washers go on the outside of the outer pulley half, then the washer and nut. Make sure the washers on the outside are on the shaft, they can slip off and you can bend them if not carful. that should be close. turn the engine one by putting it in gear and pushing the car forward a bit, re check the belt tension (about 1" play from the center of the belt). Repeat the procedure as needed removing or replacing shims to achieve the proper tension. remember, the fan housing should not wiggle at all. Any questions, please consult your bentley manual. Fan housings are expensive and break and doesn't take much to really fuch things up. at least i think that is what your talking about. keep at it

[Wew]

Thanks James. I have tightened down the fan strap and its tight now! No movement or rocking!
Everything I have read says the belt should have a 1/4" to 1/2" of play, which is where I am at with 4 washers on the inside and 2 on the outside. I have not tried pushing it while in gear though, so I will try that to see if I can get the driveshaft/fan belt to rotate.
thanks,
Gary

[James Brown]

whoo, that was close, the final tension will be up to you and how it feels. looks like your on the right track