Scottsdale86

Hello all! I've been following this forum for about a year now...basically, ever since I got my Dodge. I've found this place to be very informative and helpfull and up until this point, I've been able to find answers thru reading posts and doing searches. But I finally got stumped with this problem which leads me to my first post.

Now from what I understand, there are two different styles of vacuum pumps for our trucks...intercooled and non-intercooled. Now my question is, are the non-intercooled the "diaphram" style that have two diaphrams (one on bottom and one on the side) and are the intercooled versions the "rotory" style (no diaphrams)?? I thought I rememberd seeing this in a search I did a while back. My truck is the spilt-year 91.5 (intercooled) and it has the dual diaphram style. Is this right?? I'm just trying to see if I have the correct one on my truck before I order any parts since I'm trying to diagnose my crappy brakes.

Thanks for the help!!

wannadiesel

You can't miss the big ol' diaphragms hanging off the pump. If you don't see 'em then you have the later style.

Intercooled should be rotary, non intercooled had the diaphragms.

Scottsdale86

So, the diaphram style that's on my truck is the wrong one since mine is intercooled, right?

wannadiesel

No, they just hadn't run out of those pumps at the plant yet. Lie to the parts guy and tell 'em you have a non-intercooled truck.

flashgordon

when i went trying to rebuild my vacum pump........well there's not a lot left available. I replace one of the rod for one of the pumps and got enuff vac to make my ex-brake work in the high altitude 7000 feet.

does the intercooled vacum pumps make more or less vacum. will the p/s pump interchange?

wannadiesel

The intercooled pump makes more vacuum. Not sure about the P/S pump bolting on. I know you would at least need the drive dog for an intercooled setup. If you can score the complete vacuum pump/PS pump setup off an intercooled truck (even a 2nd gen up to '95) that would be ideal. The later pumps are too small because those trucks had hydroboost brakes, all the vacuum pump did was run the HVAC dampers and the cruise. That guy "RedlineAR" on Ebay who parts out CTD's is probably your best bet to score one.

Jim Lane

The diaphragm vacuum pumps that are used on our early first gens's will come off and can be replaced individually.
They are the exact same vacuum pump unit that was used on the 6.2 GM diesels of the 1980's and I think I paid around $65.00 each.

Anyone know,
How many full applications should we have after the engine is shut down?
I get at most 2 before I have to stand on the pedal, situation is I will pull up to a drive through speaker and shut down while still in gear or in neutral so I can order, if I let up off the brake it will start to creep.
I am working on an idea using an electric vacuum pump that will sense the engine not running and a loss of vacuum in the booster to supply a reserve.
What do you think?
Jim

JimmieD

How about a vacuum reservoir tank?

1st gen Hobie

Like one that food comes in? I saw a car that had two good sized cans under the hood to help the vacuum.

flashgordon

thanks Dave,I remember that now form a previse post were the part store gave him a non intercooled ps pump for a intercooled pump or vice a versa

flashgordon

Thats good to now because the pump diaphfram for chry was somthing $100 each and was discontinued any ways

Jim Lane

It looks like you can get then through your local Kragen, Advance, Checker, Schuck's as well as most independents.

I also think this is sold as PER UNIT not for both.

http://www.partsamerica.com/ProductL...m+Pump&ptset=A


This is a link for Parts America

http://www.websquare.com/sites/out.php?id=698


Jim

JimmieD

Yea, Hobie, like the ones used on hi-perf gassers with a high lift cam [probably what you're talking about]. They've got zip for vacuum and the can's add up the accumulated vacuum for when it's needed. JEGS and Summit have them.