Re: wiper vacuum source
It may well be that this pump is just not sufficient to the task. But, with some more testing tonight I discovered a weakness in my wiper vacuum motor that is likely contributing to the pump's inability to operate it.
With the wiper switch turned off, I'm able to get 13-14 Hg of vacuum in the line to the wiper motor. But, it fades pretty fast when I shut the pump off - like back to 0 in 2-3 seconds.
When I turn on the pump with the wiper switch turned on, I can't get more than about 2-3 Hg of vacuum. So, the vacuum motor just doesn't seal tight enough for the pump to create enough vacuum to run it.
It may be that all vacuum wiper motors are not tight enough or it may be that the pump would actually do something for a wiper motor that seals tighter. My vacuum motor has not been rebuilt with all new parts. It has just been cleaned and lubricated to work fine for me.
If anyone wants to try it out on what they think is a tighter sealing vacuum motor let me know and I'll send it for you to try out. If it works, you can pay me for it. If not, you can send it back.