86 6.9 tapping noise

[BrianX128]

Definitely replace that belt if it won't tension anymore.

But what in the hell is it routed around that's under the vacuum pump?

I don't think it is, I think it's just flapping but now that you said that I've watched that part again a few times and I think I'm starting to imagine something being down there.

 

[crash-harris]

I had to rewatch that part a few times. I swear there's something under there.

 

[BrianX128]

It's almost like there's an idler pulley down there but that's not it. I swear at 35 seconds the belt is stuck on something that isn't a spindle.

Perhaps I just need to have another beer. By the end of the night my engine might have it as well.

 

[larson]

I believe you will be fine starting the engine with belts off as long as your just sitting there in park or neutral. Vacuum is just for auto trans, brakes and ac controls. Alternator is for charging your batteries and supply power to electrical draw while running. Most important is water pump. Don't run it for to long so it doesn't over heat.
If I'm wrong someone will correct me on here.
Also check out what icanfixall was posting about your belt drive pullies. That crossed my mind also as to what that noise could possibly be.

 

[steelheadguy]

I drove it last night and this morning for about 40 miles each drive. The noise hasn't come back.

It is hard to see in the video. The alternator has two belts, a small one going to the vacuum right below it and the larger belt that goes around the crank and fan pulleys.
I tightened the belt just to be sure.

 

[steelheadguy]

The noise had nothing to do with the belts. My ignition switch was acting up and not returning the key to the right position. This caused the start anf flywheel to make the noise. New ignition switch and all is well.