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| | | | Joined: Dec 2006 Posts: 13 New Guy | | New Guy Joined: Dec 2006 Posts: 13 | I know What it is, and I have a good idea that it connects to the 3 vac hoses dangling underneath the drivers side of the cab...but why was it on the passenger side floor? I guess my questions is...what do I need to know about this thing, and, since it was removed, I assuming that something's wrong with it. Are they repairable/rebuildable? On line source? It says Midland 30J308 or 300308 | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | what you need to know is with hoses dangling, you've got no brakes! hydrovac brake booster kits - maybe available locally too Bill | | | | | Joined: Jul 2004 Posts: 5,708 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 5,708 | Yasmar, Although I'm all for rebuilding most things, your old rusty Hydrovac would make a wonderful core for a factory rebuilt one purchased from your local supply house. The Midland numbers should pin it down for the guys at the counter with the purple hair and pierced noses.  Stuart | | | | | Joined: Dec 2006 Posts: 13 New Guy | | New Guy Joined: Dec 2006 Posts: 13 | So which one do I need? It's just a seal and gasket kinda thing? | | | | | Joined: Jul 2004 Posts: 2,991 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 2,991 | I think Stuart is suggesting that the entire unit could be replaced with a rebuilt one, and that the old one could be turned in as an exchange, or core. It may a lot less hassle than trying to rebuild yours. Personally, I've never dealt with one of these, so I have no idea. | | | | | Joined: Feb 2005 Posts: 199 Wrench Fetcher | | Wrench Fetcher Joined: Feb 2005 Posts: 199 | There is a Tech Article on rebuilding the hydro vac unit in the tech page.
The article deals with single vac units but I think the approach will be similar for the two stage units.
The parts are available or as has been suggested you may want to opt for a rebuilt unit.
Also the shop manual has instructions for rebuilding with excellent parts breakdown.
Hobert
"The Lord is my shepherd"
| | | | | Joined: Sep 2001 Posts: 581 Shop Shark | | Shop Shark Joined: Sep 2001 Posts: 581 | In St. Louis, we have a nearby Precision Rebuilders, which rebuilds components of medium and heavy- duty trucks, such as air compressors, air cylinders, and yes, hydrovacs. They supply most of the local truck shops with remanufactured parts, but I understand they will work directly with customers as well. Check out their catalogs online at http://www.precisionrebuilders.com/ and see if you find your hydrovac unit. If so, you can swap it out wth one slightly less "experienced". ;-) Good luck, and please post with your results. -Michael | | | | | Joined: Dec 2006 Posts: 13 New Guy | | New Guy Joined: Dec 2006 Posts: 13 | Upon further examination, the other side has a rust-thru issue.
What are my options as far as replacements. Does it have to be an exact replacement, or just one that's the same size? What do these normally cost? | | | | | Joined: Jan 2005 Posts: 1,602 Shop Shark | | Shop Shark Joined: Jan 2005 Posts: 1,602 | I suggest you take it to NAPA store with the numbers. They will most likely find one for you. I did it and they had one for my truck. Good luck! | | |
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