Alternator

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Max Welton
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Alternator

Post by Max Welton » Mon Sep 07, 2015 2:25 pm

So I'm installing the kit available from CB and ACN (maybe others).

http://www.cbperformance.com/ProductDet ... tCode=2183

http://vwparts.aircooled.net/CPR-s-12V- ... on-kit.htm

What do people do to seal up that big hole around the pulley?

Max
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Last edited by Max Welton on Mon Sep 07, 2015 5:40 pm, edited 1 time in total.

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Max Welton
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Re: Alternator

Post by Max Welton » Mon Sep 07, 2015 5:40 pm

Also, I need a heavy-gauge ring connector. My 68 type-3 generator took a large spade.

What gauge is the heavy wire?

Max

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aircooledtechguy
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Re: Alternator

Post by aircooledtechguy » Mon Sep 07, 2015 7:54 pm

Isn't that area technically before the fan?? There shouldn't really be a huge amount of pressurized air on that area of the shroud to worry about. 'Course I'm not running a type3 motor so YMMV. . .

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Max Welton
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Re: Alternator

Post by Max Welton » Mon Sep 07, 2015 8:15 pm

Yes, that part of the shroud is low pressure air on it's way into the fan. If that space is unsealed warm air from under the deck is pulled into the cooling system. Probably not much of a problem when moving, but if you stop, that upside-down tub that is the engine bay fills with hot air.

Max

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Max Welton
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Re: Alternator

Post by Max Welton » Sun Sep 13, 2015 5:32 pm

So the alternator is in and the wiring mods complete. The car has been down for three weeks but it fired at the first hit of the key. Bus voltage went straight to 14 at 1000 engine RPMs as seen by the MS2.

I haven't done anything yet to fill the big gap around the pulley. I will probably fab something but will be watching temps closely in the meantime.

I am also a little concerned with the belt tension. It seems a little tight at the limit of adjustment. I am used to running the stock belt a little looser, but the stock pulley is larger than what came on the alternator.

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Piledriver
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Re: Alternator

Post by Piledriver » Sun Sep 13, 2015 7:04 pm

The T4s have a filler piece there around the alt, would be too big for that alt/hole, but may provide some ideas.
It is actually setup to seal around and draw air through the alternator, which has forced air cooling from the fan housing on the other end.
If your setup is also blowing into the alt it may be a feature to "seal" it in a similar fashion, allowing airflow through the alt, and only through it, works as something of a dynamic seal while better cooling the alternator..
I, for one, regularly embrace our new robot overlords, as I am the guy fixing the robots...

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Max Welton
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Re: Alternator

Post by Max Welton » Fri Sep 18, 2015 3:01 pm

So here's a note for others thinking about this kit.

It comes with a 10 x 965 belt. I got the belt on, but it was fiddle-tight. Tight enough that there was a thrumming sound coming from the engine. Tight enough to change the gap between the VR sensor and the fan-mounted trigger wheel. It was giving my sync losses until the belt got some heat in it.

So I tried a 10x1005 (Napa 25 7390). It was way too loose and slipped a little. But the funny noise and the sync hits were gone.

Now I have a 10x980 (Napa 25 7380). The alternator is at the extreme lower end of the adjustment range of the bracket but the tension seems reasonable. Maybe a 10x990 would be just right.

Max

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