HI Jim--

Ours don't seem to like roughing out the H-device.  Pfieffer seems to be 
the only ones to service them--but their prices aren't too bad.  The 
ones on our XP are ok (~5 years).

Leybold trivac's were used on the 251--and we're using a relatively new 
one the 253, outside the box (too big) to pump out the H-dev for the 
time being--and the oil turned red pretty fast....hmmmm....

Maybe time for an inline filter???

take care

gerry


Jim Palandri wrote:
> What is the life expectancy of Pfeiffer Duo 2.5 direct drive rotary 
> vane pumps?
>
> Ours are waste line and inlet line (latter backing a turbo) pumps on a 
> MAT253, and are about a year and two thirds old. Initially they worked 
> great.
>
> Lately they seem to cause the pump oil to begin breaking down in just 
> a few days. They produce a decent, but not great, vacuum with fresh 
> oil, but the pressure will climb over an order of magnitude in two 
> weeks, and browning the oil. Note we are using TKO77 oil, which Lesker 
> claims is a substitute for P3. We think these pumps may be worn out, 
> but, what are the experiences of others?
>
> Also, does anyone have a 253 that was furnished with some other brand 
> of rough pumps, and, what brand(s) did the 252, 251 come with?
>