Underdrive Pulley noise

KStromberg

KStromberg

VIII looking for 8s
I confiscated a set of Steeda underdrives for the Mark VIII from my buddy. We put them on, retained the stock alt. pulley and now at high rpms say about 5000+ like at the top of the gear shifts, there is a very noticeable rough, grungy sounding buzz I am getting now. What can this be? I have already determined they are coming off because I don't like the noise at all. :eek:

The crank pulley looks just like the one Lonnie sells over at BOC, but the water pump pulley looks the same as mine, just a larger diameter. The water pump pulley is NOT the one you see pictured on BOC. FWIW, the crank pulley was just zipped on there with an impact. He did the same with his car and no problems...
 
We started it with a flat 2x6 and a hammer lining up the keyway. Tightening the bolt with washer should have pulled it on the rest of the way??? Looked good to me...
 
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Sounds like another good opportunity to use a stethoscope.....while laying on the top of the engine, running down the road at 5000 rpm in high gear.
 
Ok, so does anyone have a response other than telling me what I did wrong? Lol Obviously it's already determined that something is wrong. Nevermind, I'll just take the bastards off since that was my original plan. Don't even know why I asked.
 
Roadboss said:
That's not really how you are supposed to install those pulleys.
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Inspire me. We started it on the keyway and it was harder than **** to get it to go on all of the way. We werent beating the snot out of anything if thats what people are assuming here.
 
Well, it's off to get a new crank bolt today after work and put the stockers back on. Unfortunately, I may have learned another hard life lesson because it appears there is some "glitter" around the crank pulley area. :mad:
 
KStromberg said:
Inspire me. We started it on the keyway and it was harder than **** to get it to go on all of the way. We werent beating the snot out of anything if thats what people are assuming here.
Click to expand...

I use a Harmonic Balancer Remover/Installer kit similar to this:

http://www.summitracing.com/parts/OTC-4531/

KStromberg said:
Well, it's off to get a new crank bolt today after work and put the stockers back on. Unfortunately, I may have learned another hard life lesson because it appears there is some "glitter" around the crank pulley area. :mad:
Click to expand...

If you use a stock bolt (which I believe is a single use, torque to yield bolt - I always replace them with an ARP Bolt), then it needs to be installed in 4 steps, NOT just "zipped on there with an impact gun".

1. Tighten to 66 Lb-Ft
2. Loosen 360 degrees
3. Tighten to 35-39 Lb-Ft
4. Tighten an additional 85-90 degrees
 
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Yep, I believe overtorquing is to blame here. My buddy has saved my ass on many occasions but he really screwed up on this one. I called the local speed shop and they said it sounds like the pulley is hitting the front cover. Doug, your post is priceless and I appreciate that. You are a shining example of why I enjoy these forums even through my frustrations. ;)
 
KStromberg said:
Yep, I believe overtorquing is to blame here. My buddy has saved my ass on many occasions but he really screwed up on this one. I called the local speed shop and they said it sounds like the pulley is hitting the front cover. Doug, your post is priceless and I appreciate that. You are a shining example of why I enjoy these forums even through my frustrations. ;)
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The pulley shouldn't hit the front cover, even if it was over-torqued.

Unless you did something else, which I'm afraid to mention..... :eek:
 
KStromberg said:
Please do. There's no turning back now. :(
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I can only think of three reasons that it would hit the front cover.

1. It's the wrong pulley or it's damaged. (likely)
2. The end of the crankshaft is mushroomed or bent. (possible)
3. The thrust bearing is damaged. (unlikely)

Crankshaft end-play should be .130-.301 mm, if it's more, then the thrust bearing is toast.
 
DLF said:
I can only think of three reasons that it would hit the front cover.

1. It's the wrong pulley or it's damaged. (likely)
2. The end of the crankshaft is mushroomed or bent. (possible)
3. The thrust bearing is damaged. (unlikely)

Crankshaft end-play should be .130-.301 mm, if it's more, then the thrust bearing is toast.
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What is involved in thrust bearing replacement? I really should have questioned the installation. Assuming the crank is fine that is... I'll know in a couple hours. I had to stop for a drink after getting the new bolt. I hope my car hasn't been messed up again. I'm such a sucker. :(
 
KStromberg said:
What is involved in thrust bearing replacement? I really should have questioned the installation. Assuming the crank is fine that is... I'll know in a couple hours. I had to stop for a drink after getting the new bolt. I hope my car hasn't been messed up again. I'm such a sucker. :(
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You don't really want to know, let's just hope that's not it. :eek:

You'll need to pry the crank forward, zero a dial gauge, and then pry it back to check the end-play and the condition of the thrust bearing.

Use the right tools to remove the underdrive and to put the stocker back on. If you don't have them, then wait until you do.

Don't EVER beat on the end of a crankshaft......
 
I know people who have used impacts on the crank before and shattered the oil pump. Others have later found the inductor wheel on the crank broken or shattered.

I may be old school but I would never suggest using an impact on the crank. Some get away with it, others pay the price.
 
A big sigh of relief! It was the crank pulley that was overtorqued a bit much and wore a very small grove on the front cover. We used a new crank bolt and I opted to go back to the stock pullies. The condition of the end of the crank is straight and there was no metal within the channel. All is well and lucky I am. :eek:
 
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