I think my vacuum pump is bad...

[Commander5993]

Hey All,

We bought an 86' M1008 CUCV about a month ago out in arizona. On our way back to the hotel we noticed that it shifted hard. Checked the fluid, it was a little low, topped it off, still shifted hard. So called the guy back up, he tried to say that it was "normal" for the CUCV to shift hard "just check Steel Soldiers, they all shift hard" .

I knew this didn't sound right, but the hotel internet was pretty pathetic. However I did see some of the solutions like bad vacuum lines and all that. So I thought I would just look more into once we got it back home.

Now, I have already replaced all the vacuum lines. Still no change.
So I bought a vacuum pump and gauge to adjust the valve.

Hooked it all up today according to the TM. Loosed the two screws to adjust the valve, and noticed that it was already adjusted as far back as it would go toward the firewall. Using the pump, got the HG up to 20 on the supply side, and the gauge showed around 8 hg on the output side.

So I connected the gauge to the vacuum pump, and started the truck. At idle, the gauge bounced around 0-5 HG. Revving the engine a little didn't really change much. Now I know it might bounce somewhat due to the diaphragm in the pump, not sure how much is normal though.

I tried to search here, and then in the TM. But couldn't find out for sure what the pump HG output should be at idle, but my guess would be around 20 hg???
Does anyone know what is the correct HG output for the pump at idle?

Also does anyone know if this is a CUCV type pump Only.
Or if an off the shelf Civy pump will work?

Thanks!!

 

[ryan77]

Yes sounds like you need a vacuum pump! 5 is way to low at idle! I got mine from autozone!

 

[mudman]

I have been thinking about this "little sucker" lately myself!!!

 

[Commander5993]

Thanks Ryan77, at least I know that it is the pump now.

I found the OE New Delphi on advance autoparts website for $186 with their 15% off online orders. And a rebuilt one on autozone for $108.

 

[ryan77]

I got the autozone one i think its a lifetime warranty!

 

[80sturgisrider]

Source for vacuum pump

I got the autozone one i think its a lifetime warranty!

WOW--$108.00? I bought one from KOI (use to be NAPA) yesterday for 76.90 out the door--lifetime warranty.

 

[Commander5993]

The Local Napa wanted $242 for a New OE Delphi vacuum pump.
And $125 for a Napa brand rebuilt vacuum pump.

So I ended up ordering a rebuilt unit from autozone.com for $108 w/ free shipping.
Plus they had some special running that if you order over $100 worth of stuff through their website and then select the "home delivery" option, you get a $15 gift card.
Need to get a couple mobile 1 oil filters anyway, so the card will at least buy one. And the autozone in town is the only local place to get mobile 1 oil filters for some reason. None of the other parts stores carries them.

Anyway, should get the pump in a few days, and get it installed.
Hope that's my only problem.

Thanks Guys!