[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [New Search]

Re: [T3] 74/78 crank?

On 17 Nov 2003 at 22:20, Greg Irick wrote:

> Aircooled.net sells a tool that you use to clean up the oil piston 
> seating surface, 

> http://www.aircooled.net/new-bin/viewproductdetail.php?keyword2=TZE0029

I've got a lot of respect for John at Aircooled, but I've got to wonder how 
this could possibly be true. Since the piston only sits against the top of the 
bore when the pressure is extremely minimal, The only time this might have any 
effect at all would be at idle.  

I suppose if the top of your bore was poorly finished, you might get some 
improvement at idle, but once you're off idle nothing changes. Certainly 
there's nothing wrong with improving the idle oil pressure, but keep in mind 
that the load on everything is also minimal at idle, and your engine spends 
very little time there.  

Maybe I also need to take a look at how the dual valve cases are made. It's 
possible that the cooler bypass valve (the rear one) would benefit from such a 
cleanup. If that kept oil from leaking around the piston when the engine was 
hot, then it would put more flow thru the cooler and make the engine run 
somewhat cooler, which would up the pressure slightly at all rpms.  

I also can't be sure, but this looks like a lot of money for a pretty standard 
cutter. Does anyone know the diameter of the pistons or bores, off hand?  I'd 
also have to know the depth of the bore.

Hmmm, good food for thought....

Jim Adney
Madison, WI 53711-3054

List info at http://www.vwtype3.org/list | mailto:gregm@vwtype3.org

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [New Search]