recommend front pulley brand

[dblevins]

I am searching for a quality front pulley on my fst.I have blown seals out the last 3 races ,( the seal comes out of the insert). I am running 60 # oil pressure,cold.I thought I had a SCAT,but am not sure now.Any suggestions and /or suppliers ?

[Stirling 306]

Dave, look up CB products.
http://www.cbperformance.com

[rave motorsports]

Dave
Use a sand seal.

[dblevins]

I do have a sand seal,that's the seal that keeps leaking.

[Steve Davis]

What kind of breather do you have for the crankcase? What size hose? It needs to be pretty BIG - at least 1/2 inch, but 3/4 would be better. If the crankcase pressure can't VENT, then it seeks other ways to get out. In most cases, the crank slinger on the front keeps the oil in and no seal is needed. The sand seals are intended to keep sand OUT, rather than keeping oil in, although they DO help a bit in that regard. *BUT* if pressure is building up inside the case and can't get out fast enough, no amount or brand of sand seal is going to keep the oil inside.

[rgu]

Dave
We had the same issue two years ago and we used our whole stock of seals and didn’t fix the problem. He are things that happened on a couple of cars.
Bill Bonow just tossed out the sand pulley and seal and used the stock VW pulley to screw the oil back in the case. He seemed happy with this.
Doug Seim had a lot of leakage around the sand seal because the seals were falling out. I assume that’s your issue. Our engine builder (Dave Carr) told us there were a couple different sand seal sizes so we gave up on the spare seals and bought a new Scat pulley (the one w/o the groove) and a spare seal just for that unit. That worked just fine.
The last problem might be something you need to look at. The case surface the soft aluminum seal housing pushes into can vary. Which is why our rules allow you to machine the case for an oversized seal. This might also be the issue.
Steven’s point, while valid, is not as important with our dry sump pump as it is on a vee. While our scavenge side does not create a suction in the case as would a more aggressive pump they isn’t a whole lot of oil in the case.

[Hardingfv32]

EPOXY everything

Brian

[dblevins]

I appreciate all the answers.I have -10 an fittings in each valve cover,routed up to the oil tank,which is vented using a -10 hose into the overflow tank,along with a -6 hose from the generator base to the overflow tank. I don't think lack of venting is the issue. I pressurized the oil system by removing the hose going into the oil filter,plugging it off,and pumping 50# of air into the oil filter.Air was venting into the overflow via the oil tank vents,so they work properly.

[Bill Bonow]

Sand seals are designed to keep sand out of a dune buggy engine, The seal lip is typically backwards for sealing oil. I had similar issues, went back to the original VW set up and no more issues/leaks.

That was my results, YMMV

[gbmetcalf]

I see a lot of turned down pulleys. Does this give you an advantage? Or is it just a personal preference?

G.

[dblevins]

That pulley was purchased like that.I assume the smaller size keeps the rotating mass a wee bit lighter.Also,at the time I needed a thin pulley to clear the oil tank,( an issue which has been resolved by lengenthing the frame).

[Steve Davis]

I see a lot of turned down pulleys. Does this give you an advantage? Or is it just a personal preference?

G.

In older times, the stock front pulleys would eventually crack and had to be replaced. Now that the pulleys are 'free', it's easier (and cheaper) to just chuck it up in a lathe and turn it down to round again and keep using it

[Daryl DeArman]

I see a lot of turned down pulleys. Does this give you an advantage? Or is it just a personal preference?

G.

Yes. Any mass that needs to be accelerated takes energy. The lighter and smaller the diameter of the spinny thing, the less energy it takes.

Consult the GCR before you chuck it up in a lathe, I believe there is a minimum OD, but it's been a while.

[problemchild]

Some builders think it's better to have a pulley than a cut-down hub. Having a nice correctly marked pulley is preferred when its time to set the timing (with accuracy).

[MrGas]

The best pulley for VW motors is a VW pulley. Aftermarket parts vary too much. And its a sand seal to keep sand out , not oil in. is the seal leaking or just blowing out?

[dblevins]

Based on the input I've received,I'll probably go back to the stock style pulley.The inner part of the sand seal was coming out of the outer ring, allowing oil to be thrown out around the pulley.