should I replace mech vac pump with 12v electric pump on M1009

[cucv newbie]

Has anyone ever tried to replace the mechanical vacuum pump with a 12 volt electric vac pump. I am told that early eighties GM 4 cylinder cars used such a pump to run the HVAC controls. My mech pump is toast so, the trans is very erratic. I was thinking there must be some gain in removing the mech pump from the already underpowered 6.2L. I have already replaced the vac lines. Mech vac pump is confirmed DOA. If you apply vacuum with a hand pump at start up, it shifts fine. Any thoughts? Thanks

 

[Recovry4x4]

My solution was to switch to a 700R4 and skip the need for vacuum.

 

[Warthog]

You have to have something to drive the oil pump. If you remove the vacuum pump your engine will last for a few minutes.

 

[cucv newbie]

Great idea except, I just paid a whole bunch for the rebuilt TH400 and new torque converter. Right or wrong, it is done. Thanks tho

 

[Keith_J]

The vacuum pump is part of the calibrated system that makes the TH400 think it is behind a gasoline engine. The vacuum regulator valve attached to the injection pump has a variable pressure and a set leakdown rate for the variable pressure.

This makes the vacuum vary with throttle position just like a gasoline engine. Changing the vacuum pump to a constant volume unit driven by an electric motor would negate this design. The stock pump has a volume flow rate proportional to the engine RPM and the regulator's position.

Don't do it.

 

[cucv newbie]

You have to have something to drive the oil pump. If you remove the vacuum pump your engine will last for a few minutes.

Hmmmm. didn't think about that. So should I just abandon it in place? Or just buck-up and buy a new mech pump?

 

[Warthog]

Why not buy a used one? New ones are not cheap.

 

[cucv newbie]

Ok, I guess that answers why I couldn't find info on this alteration. Thank you, any thoughts on where to buy a new or refurbished mech vac pump?

 

[Keith_J]

Rockauto? I'm no way connected to this company nor am I endorsing them. Check part numbers against the technical manual -P.

 

[m38inmaine]

Last new one I bought was from here http://www.flmv.net/FLMV-CUCV.htm, or you could check here for a used one http://hillbillywizard.com/CUCV.html

 

[cucv newbie]

can these be rebuilt?? If not, does it make sense to buy a used one, or will I have this problem again in the near future. The 1009 is primarily only used for hunting once a year, and occasional joy riding and 4 wheeling.

 

[Warthog]

Rebuilt ones at your local parts house.

Oreilly's
Cardone 64-1201 - $110 rebuilt
BWD VDV15 -$280 new