Which dry vacuum pump is best these days?

[Jim_R]

I've got a Cherokee with an O360-A4A. The Rapco that's currently on it is about 700 hours old and I fly IFR, so I'm considering a preemptive replacement.

Google isn't showing me much recent discussion about vacuum pumps. Best I found was this five-year-old Aviation Consumer article: https://www.aviationconsumer.com/maintenance/vacuum-pump-trials-which-sucks-best/

Any compelling reasons why one vacuum pump stands above the rest these days?

 

[asicer]

The best vacuum replacement these days seems to be a G5 or GI275.

 

[Jim_R]

The best vacuum replacement these days seems to be a G5 or GI275.

Maybe, but I specified "vacuum pump", not "vacuum".

 

[Gary Ward]

One that has a inspection port, Rapco or Tempest.
Good move replacing it ahead of time.

 

[Bell206]

One that has a inspection port, Rapco or Tempest.

^^^^ This. But you need to check the vanes as recommended for it to make a difference.

 

[robin ardoin]

The best vacuum replacement these days seems to be a G5 or GI275.

Ha…. which is what I did and removed the pumps. Which reminds me, one of the pumps probably has under 75hrs, RAPCO, and I need to sell it. If it fits your engine I’ll let you have it for a very reasonable price.

 

[Gary Ward]

Might as well put a new oil seal in when you replace it also.
Don’t ask how I learned that.

 

[Jim_R]

Might as well put a new oil seal in when you replace it also.
Don’t ask how learned that.

The Tempest apparently comes with a replacement gasket.

 

[Gary Ward]

No the oil seal between the assy case and the pump. It keeps your new pump dry.

 

[Jim_R]

Ha…. which is what I did and removed the pumps. Which reminds me, one of the pumps probably has under 75hrs, RAPCO, and I need to sell it. If it fits your engine I’ll let you have it for a very reasonable price.

Thank you, but while that might be an excellent solution, I'm going to stick with a new pump. I'm sure there would be others--especially clear-weather VFR pilots--who would snatch up that deal in a heartbeat.

 

[Jim_R]

No the oil seal between the assy case and the pump. It keeps your new pump dry.

Sorry...I don't know what the interface between the pump and the case looks like. What is the included gasket for, if it's different from the oil seal you're talking about? Where would I go to order the oil seal you're talking about?




The Tempest supposedly includes a design feature that prevents oil intrusion into the pump, fwiw:

​

 

[Dan Thomas]

There is likely lots of life left in that pump. Rapco made a couple of different measuring tools to check the vane wear so that you could maximize the life you get from the pump without it failing on you;


https://www.rapcoinc.com/pdf/Service letters/Rapco Service Letter RASL-001_Rev_C.pdf

https://www.rapcoinc.com/pdf/Service letters/Rapco Service Letter RASL-006_Rev_A.pdf

A new pump comes with the measuring tool. It takes maybe five minutes to check the wear. Replacing a pump that has that vane wear check provision at 700 hours is a waste of money.