Posted By: 340KID
vacuum res can question - 09/09/09 07:28 PM
I installed a summitt vacuum can resev on my Cuda 340 - I plumbed it as follows, from intake to check valve on can, brass fitting on can to checkvalve on power brake booster. For some reason it is not working ! The brakes are rock hard, If i disconnect the can and go direct to the brake booster the brakes work, I added the can since i have approx 12-13 hg at idle !
Do I need to remove one of the check valves ?
Posted By: therocks
Re: vacuum res can question - 09/09/09 07:31 PM
Mine I just used from vacuum to can can to check valve in booster.Should still work as long as the valve isnt backwards.Just run hose valve at can hose to valve in booster.With 13 inch vacuum your brakes should still work even without it.Rocky
Posted By: 340KID
Re: vacuum res can question - 09/09/09 07:40 PM
I was thinking of hollowing out the checkvalve on the can and using it that way, the checkvalve on the can only has one nipple on it so it can't be backwards.
Posted By: D_C
Re: vacuum res can question - 09/09/09 07:57 PM
Did you follow the directions that came with the Summit vacuum reservoir? Have you tried hooking it up the other way?
Definitely would NOT recommend destroying the check valve. It would be useless as a vacuum reservoir if you did. Without that check-valve, the reservoir is more or less like just a big section of hose.
Agree with above, 12-13 in/hg "should" be enough to allow the brakes to work, but only you can judge how much improvement you see after you get the reservoir working.
I added a vacuum reservoir to my '71 Charger, but it only has around 6" in/hg at idle.
You can "Test" the check-valve with a hand-pump vacuum tester, or "perhaps" with a length of hose by mouth.
I could be defective, but I doubt it.
Posted By: 340KID
Re: vacuum res can question - 09/09/09 08:01 PM
The car is a 4 speed,
The can has 3 ports, one for vac guage, brass 90 degree fitting, and the hole/grommet for the checkvalve,
I tested the checkvalve on the can and it seems to be working!
Posted By: D_C
Re: vacuum res can question - 09/09/09 08:06 PM
Are there any Instructions?
Posted By: D_C
Re: vacuum res can question - 09/09/09 08:14 PM
Is "this" the reservoir (or similar?)
Seems like you have it correct. You do have the
White Check-Valve connected to the Intake-manifold source, and the
Barbed Brass connector connected by hose to the Factory Check-Valve ON the Power-Brake Booster, correct?
What about your intake vacuum source? It does receive full manifold vacuum, correct?
Posted By: 340KID
Re: vacuum res can question - 09/09/09 08:14 PM
yes there is. I installed it as in my first post
here is the can
http://www.summitracing.com/parts/SUM-G1464/?image=large
Posted By: Sub95
Re: vacuum res can question - 09/09/09 08:24 PM
there is a check vavle backwards.
when i put one in it will go as
intake to check vavle ( need to be able to blow through it ) to reservoir, to brake booster check vavle ( need to be able to blow through it.
Posted By: 340KID
Re: vacuum res can question - 09/09/09 08:36 PM
yes that's exactly how i have it hooked up,
it's just strange that it's not working,
I will have to play with it tonight if i get a chance or just get rid of the thing all together
Posted By: 70sixpkrt
Re: vacuum res can question - 09/09/09 08:40 PM
I had the exact same one about 5 yrs ago and shelfed it. I switched to manual disc since I did not have enough vacuum to run my power disc brakes.
Posted By: D_C
Re: vacuum res can question - 09/09/09 08:56 PM
Just checked/verified and Mine has Both check-valves (One on the canister, one on the power-brake booster.)
Try hooking it up the other way, Brass-Barbed Connector to Intake-Manifold and White Check Valve connection (by hose) to the Factory Check-Valve on the Power-Brake Booster.
I did mine many, many years ago, so my memory is a bit hazy on the subject, but it seems to me I had mine hooked up wrong initially, then I tried it the other way and it worked.
I just can't remember now which way that was, and the connections on my reservoir are not as obvious as the ones on yours.
Anyway, try it the other way, it just may work.
When you consider the operation... all the air flows TO the intake manifold. Logically, it seems like it should have a check valve between Manifold and Vacuum Reservoir, but perhaps not or perhaps the One-Way check-valve is not working in the correct direction of flow.
All I know, is that it "Should" work or at least allow the brakes to still work as they did without the vacuum canister.
On mine, without that Vacuum-Booster, I have about One, Good Pump on the brakes. With the vacuum-reservoir, they pretty much function as well as the brakes did from the Factory with a factory cam-shafted engine.
however what is your reading in gear at low idle a big cam will seem to be fine while parked but under load i seen it drop from 15" done to 5" Also if it doesn't need the can i would just put it aside until you need it. You just will be adding more stuff that could go imo wrong.