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1983 6.2L rear mount vacuum pump

Truckman4life

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Any one have to buy one these gems lately? I'm having trouble finding any where that I can get one without a long wait. I found one place on ebay that is selling them listed as new from GM but it comes up under the Cardone reman part number also. $98 plus $8 shipping from Ohio. The best deal I've seen so far. Mine is leaking oil badly out the air inlet on the center of the diaphragm housing.
 
I needed one about a year ago,and a member here was kind enough to send me one from CA..
I used only the vacuum can,I swapped it onto the one that was still in my engine..and I think the diaphram in that one has a rip in it now,the vacuum is unsteady and the TH400 still drags out the 2-3rd shift..
I consider these pumps to be a lousy arrangement to produce vacuum for a tranny or other accessories..

Trying to find one here in a salvage yard was fruitless--the few I saw were in "complete" engines they did not want to strip any parts from..

Your pump housing (the part where the shaft goes) might be hogged out,or it could be your engine is producing a lot of blow by or crankcase pressure--if the CDR valve goes south or gets clogged with crud it can pressurize the crank case and make oil come out in other places like seals,gaskets,and that "breather" hole in your pump canister..if the diaphram has ruptured ,just a new "can" might fix it,but last time I looked those were over 100 bucks alone..and a complete unit was up to 200 bucks,so I guess the price you found isn't that bad..

I read online the "cans" off Ford 7.3's and the belt driven GM pumps on some 6.2's are interchangeable,had I known that before I went boneyard hunting,I could have snagged one,there were some cannibalized Ford 7.3's around..
 
Yeah I kinda figured the same so I ordered the one off eBay. My other idea was to do like an electric one off a Ford super duty. They only like $60 and you need a canister to go with it. Does the vacuum pump I have also drive the oil pump like on the gassers? How bout on a 6.5 I know they are belt driven but do they have a drive in the hole in the block for the oil pump also just minus the pod part?
 
Yes,the vacuum pump has a housing almost identical to a distributor on a gas engine,that drives the oil pump via the camshaft--6.2's and 6.5's without any need for vacuum like one tons with manual transmissions and no A/C or emission devices use a "dummy shaft" with a freeze plug like cap over it where a vacuum pump normally would go,to drive the oil pump..
I have a '87 6.2 out of a C30 ramp truck that snapped the crank--just my luck,when I went to grab the vacuum pump off it when mine died,I found out it didn't ever have one..:doah:..figures I'd have the only one without one, in my possession..:surepal:..
 
if you go with an electric vacuum pump get an AC Delco 21597 oil pump drive from a 6.5l. It just happens to come with a tach signal generator! I got one off of ebay a few weeks ago. Paid $35 for it...:thumb:

FYI, the shaft for our diesels has a hex drive vs. a slot like a gasser...
Rock Auto wants $249.79...plus shipping...:eek:

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215-97_Primary.jpg
 
if you go with an electric vacuum pump get an AC Delco 21597 oil pump drive from a 6.5l. It just happens to come with a tach signal generator! I got one off of ebay a few weeks ago. Paid $35 for it...:thumb:
FYI, the shaft for our diesels has a hex drive vs. a slot like a gasser...
Rock Auto wants $249.79...plus shipping...:eek:

pic
215-97_Primary.jpg
Awesome info to know. I'll have to save that part number. What kind of tach do you run with that?
 
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Guess I'd better save that dewhickey if and when I ever do anything with that "cracked crank" 6.2 :eek:...thing has likely rusted up enough inside to be seized junk by now...
 
I'm not at the moment. I've been eye-balling the factory tach clusters. Just need to find one at a sensible price...
 
if you go with an electric vacuum pump get an AC Delco 21597 oil pump drive from a 6.5l. It just happens to come with a tach signal generator! I got one off of ebay a few weeks ago. Paid $35 for it...:thumb:

FYI, the shaft for our diesels has a hex drive vs. a slot like a gasser...
Rock Auto wants $249.79...plus shipping...:eek:

pic
215-97_Primary.jpg

Wait...what? $35 for a tach signal that gets rid of the vacuum pump? SIGN ME UP!

This is welcome news to me, 2 of my 3 rigs have no use for vacuum at all (and the third just needs HVAC control).
 
The pump I got sent to me from a member here had some kind of sensor on it that a plug would plug onto,but I think its for an ECM transmission speed sensor,not a tach..
 
The pump I got sent to me from a member here had some kind of sensor on it that a plug would plug onto,but I think its for an ECM transmission speed sensor,not a tach..

What's the difference? Engine speed is engine speed, right? You just need a gauge that can decode that particular electric signal.
 
I know right? that was what I thought when I stumbled across it...how did it remain a secret for so long?

Wait...what? $35 for a tach signal that gets rid of the vacuum pump? SIGN ME UP!

This is welcome news to me, 2 of my 3 rigs have no use for vacuum at all (and the third just needs HVAC control).
 
if you go with an electric vacuum pump get an AC Delco 21597 oil pump drive from a 6.5l. It just happens to come with a tach signal generator! I got one off of ebay a few weeks ago. Paid $35 for it...:thumb:

FYI, the shaft for our diesels has a hex drive vs. a slot like a gasser...
Rock Auto wants $249.79...plus shipping...:eek:

pic
215-97_Primary.jpg

Where did you find that price? I'm seeing that part number next to $300 prices. :1zhelp:
 
used on ebay. check the salvage yards, should be easy to find one.
 
Maybe in your state!--I searched every local salvage yard and called many others,only the place I frequent the most actually had ONE Suburban with a diesel,and the owner of the yard didn't even remember it,he said "I doubt if there is any left,we scrapped all the square bodies last year"..."and I doubt we saved any 6,2's,we only had a few ever come in..(I bought the plow pump,pulleys and brackets off one Blazer they had for 40 bucks when I got my pickup in '03..it was still there up till last year too..

I found the Suburban lying on top of a wall of huge stones and it was basically trashed--had barn doors though,rear A/C,and I think a 6.5 turbo,looked like a '91, but all the ways to ID it were gone--no doors,radiator support was missing stickers and the windshield was smashed right where the VIN tag was..
..parts were missing off the turbo plumbing,which had peaked my interest for about one second,then said "screw that ,trying to put that on either of my trucks!"..

Then I saw there was no vacuum pump in the rear--found a belt driven one on the lower passenger side of the engine..I figured it was not useable in my truck,but later I read online the vacuum can would have fit my rear drive one..

They also had a V8 diesel in a truck box that I couldn't determine if it was a GM or what--it resembled a 6.2 but the intake was missing and the valley area was not the same as mine--rocker covers looked different too,might have been a 6.9 IHC or a 350 Olds diesel--it had a vacuum pump like mine though,and perhaps the "can" would have fit mine if not the whole thing--but they wanted 75 bucks for it--they dropped the price to 60 when I said I'd rather buy a new one with the 75 bucks,but I passed--it looked like it sat there 15 years and it was a good bet the diaphram in it was junk,just like mine..
 
the part I described came off of the 92 up 6.5l trucks.
 

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