Author Topic: Supercharger belt slipping on full boost  (Read 4561 times)

Offline kwijibo_coupe

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Supercharger belt slipping on full boost
« on: March 02, 2014, 10:43:34 pm »
Looking for a second opinion before I dismantle the car.

Basically the car drives fine on and off boost until I rev it past 5k rpm on full boost.
At that point the belt starts slipping and the boost drops off.
Off boost I can rev it past 5k with no issues.

I've converted the car to run a micro V-Belt for the charger, the belt has only done a few hundred miles and is nice and tight.

Was thinking alternator bearings on their way out but when I noticed the boost dropping off and I've got it in my head the charger might be the issue.

Any suggestions?

Offline Andy

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Re: Supercharger belt slipping on full boost
« Reply #1 on: March 02, 2014, 10:50:07 pm »
Micro v-belts are shite for a G40, they need another tensioner to work properly as they're designed to wrap-around the pulleys a lot more than they do on a PY lump. You tried it with stock v-belt pulleys?

Offline kwijibo_coupe

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Re: Supercharger belt slipping on full boost
« Reply #2 on: March 02, 2014, 11:07:50 pm »
I have thought about changing it back to the stock belts.

I went for the micro V belt as I was really wanting to go for toothies but scared of stripping belts so saw them as an alternative.


Offline PeteG40

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Re: Supercharger belt slipping on full boost
« Reply #3 on: March 03, 2014, 07:53:45 am »
Tried sticky belt dressing before removing em? Also if its a new belt they stretch.

Offline Jacque

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Re: Supercharger belt slipping on full boost
« Reply #4 on: March 05, 2014, 09:03:33 am »
had the same problem with my stock belts,

i tried shorter bellts (as i ran smaller pulley) & a tool for putting some good tension on the bellts. Never had slip since...

Offline Tav

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Re: Supercharger belt slipping on full boost
« Reply #5 on: March 28, 2014, 12:55:37 pm »
Just keep a couple of spares in the car and on long trip whatever tool is required for changing them...for toothies that is.

Offline Matty!

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Re: Supercharger belt slipping on full boost
« Reply #6 on: March 28, 2014, 05:15:21 pm »
+1 for belt dressing, worked a charm on my Vbelts.

Offline kwijibo_coupe

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Re: Supercharger belt slipping on full boost
« Reply #7 on: March 29, 2014, 12:32:51 am »
Bought a toothed belt kit and on changing over to this I discovered the reason for my belt slipping issue.

The bolt holding the bottom alternator support to the block had shaken itself loose. So loose it had fallen out.

All sorted and now running toothies. Wish I'd done this in the first place. No issues with the toothies so far so I'm really happy with them.

Offline Jezza-7

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Re: Supercharger belt slipping on full boost
« Reply #8 on: March 29, 2014, 02:18:31 pm »
Just dont hit the limiter with toothies.

Offline kwijibo_coupe

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Re: Supercharger belt slipping on full boost
« Reply #9 on: March 30, 2014, 11:26:46 am »
So I've heard, never hit the limiter in the G40 anyway but I'll be more careful now.