OEM crank pulley diameter

[ottobevis]

Hi,
I need to buy a 6-3/4" T1 crankshaft pulley. I'd prefer to buy new but am not sure of the correct part number(s).

It needs to be 6 3/4" or less (7" is too wide as I have an oil line coming out next to it for a cooler/filter). It is being fitted to a universal AS41 case along with a 30amp 12v generator if that makes any difference to the snout diameter or length of the pulley.

I've seen some part numbers online (such as 111105251 A/B/C etc) but they do not list the diameter. If anyone has a part number that would be great. Thank you.

[rcooled]

Around Ø7" was stock for a 1600 motor. Anything smaller will reduce air flow and compromise engine cooling.

"Power" pulleys are Ø5 3/4" but are not generally recommended.
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[Glenn]

The stock size for a 1600 based engine is 6-3/4".

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Glenn
74 Beetle Specs | 74 Beetle Restoration | 2180cc Engine
"You may not get what you pay for, but you always pay for what you get"

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#BlueSquare

[esde]

What engine is it going on? 36/40/15/1600? The pulleys are all sort of interchangeable, but there are differences.
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modok wrote:
Bent cranks are silent but gather no moss. I mean, ah, something like that.

[ottobevis]

Thank you for your replies. It's a 2176cc, AS41 case, redline 6,500 RPM, doghouse, 37mm wide fan.

I had been thinking about using a 5 3/4" pulley, just because of the higher engine RPM to reduce belt slipage, but for now I will use a stock steel OEM 6-3/4".

Is there ever a need to place a shim/spacer behind the OEM crank pulley to get correct alignment with the generator pulley? I have a regular 30amp 12v generator. I know on aftermarket pulleys this is sometimes required. On the previous pulley I had installed (empi or similar aluminum) I did not use a spacer/shim (and I should have). I didn't realize the generator pulley was sticking out further to the rear by 1/8". First test drive the 36mm crank bolt came off (I think due to this although I may also not have torqued it correctly). I just don't want to put the new crank pulley on only to find it's too far forwards and then have to try and remove it without bending it (doing this with the engine in the car).

[richparker]

7” is the stick size. I run a 7” Billet CB pulley on my 2175 and a 6 3/4” CB Equalizer pulley on my 2275.

https://www.cbperformance.com/Crankshaft-Pulleys-Accessories-s/240.htm

Seems weird that you have an oil line in the way and can’t use the 7” pulley. Can you post us a picture of your set up.
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[esde]

[Glenn]

CB sells a shim kit to space the alt/gen and the crank pulley... i've never needed to so that.
_________________
Glenn
74 Beetle Specs | 74 Beetle Restoration | 2180cc Engine
"You may not get what you pay for, but you always pay for what you get"

Member #1009

#BlueSquare

[ottobevis]

Thanks for your feedback. So it could be my aftermarket 36hp doghouse shroud pushing the generator rearwards that's causing the issue. I may still need a spacer/shim behind the OEM pulley to get the correct alignment with the generator pulley.

I think my safest bet is to use a crank spacer, install and torque the crank pulley. If I then find the crank pulley too far rearwards I can just use a generator pulley spacer/shim (not the shims for belt tension but the smaller aftermarket washer for pulley alignment). I think this will be easier than trying to remove the pulley with the engine in the car.

The crank pulley is a tapered fit right? In other word's the crankshaft end and/or pulley are slightly tapered, causing the pulley to fit snug. The snout of the pulley should not bottom out against the oil slinger in the case.

[kreemoweet]

[esde]

The pulley is what keeps the slinger from riding loose on the crankshaft
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modok wrote:
Bent cranks are silent but gather no moss. I mean, ah, something like that.

[ottobevis]

Thank you for confirming. Now I think about it that makes sense (why sell aftermarket spacers/shims if it were tapered).

I probably need around 1/8" worth of crank shims to get it right. Will measure once I take the engine support bar off.

Another issue that may not helping is a gap between the silver generator body and the backing plate (about 1/8"). I'm wondering if this is normal or if I should take the backing plate off and try and bend it closer where the generator touches it so there is no gap?

It's probably my fan shroud that's the problem. It's aftermarket and I spent quite a bit of time bending and welding (filing in) the edges to make sure it fitted tight in to the cylinder tins. I also glued a thick foam gasket around the doghouse cooler. So basically the shroud is probably too far forwards and is not flexing when the generator is pushed forwards. If the engine was out of the car I would loosen the shroud bolts and move it forwards a bit. But as I am not removing the engine I will use crank shims.

[rcooled]