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Was driving home yesterday and went to the brakes when entering driveway . Had real hard pedal and was hard to stop car . Went out this morning to see what was going on and what happened was the T in the vacuum line busted , so easy fix . But when I took the old one out there was some lite oil in line . Is this normal the master was full and I had the booster replaced two years ago .
I don't know what year you have but most do not have a T off the vac brake line, they have a single line for brake vac only..is there a filter on your vac line ?
Its in the garage covered up . I will look tomorrow ,not positive but it might be the vacuum advance . The person tuning it said there were lines ran wrong , I told him put them were they belong . When I got it back it ran the best it ever has so I didn't look to see how he ran things everything was working . Was just wondering about the oil .
Do your power brakes feel perfect normally? Being that you have it on a T and connected to something else, I imagine it's not on the stock 3/8" size of vacuum line so I wonder if whatever line you've got there is wide enough to support sufficient vacuum pressure for the brake booster.
Ok went out and looked . Brakes seemed fine before the tee broke . . Theres two tees in the line . one goes to the trans there other to the lights . The lights are a little slow but they were like that since I got the car .
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
Check your PCV valve to make sure its moving freely. The only way to get oil in the vacuum is sucking it through the carb. make sure there is a baffle were the PCv is connected. Replace the tee with a brass one, you can get them at Lowes or Home Depot
...Theres two tees in the line . one goes to the trans there other to the lights....
These should run from the intake manifold fitting and not off the brake booster line. Brake booster should run from the base of the carburetor over to the booster with nothing else on it. The PO has not done you any favors.
Was looking it over heres what I have quickfuel hr-680-vs . It has 1 large vacuum port on the back which is going to the pvc . on the front pass side it has 1 port low which is connected to the dist. and 1 port high that was capped don't know why . Can I run the lights and the trans off that port . right now the booster, lights, trans is coming off the intake all together .
I'm guessing the higher of the two ports is "ported" vacuum meaning there is only vacuum present as the engine increases in rpm. Ported vacuum is above the throttle blades of the carb. Pull both lines off and see if either has vacuum at idle and 3000 rpm.
These should run from the intake manifold fitting and not off the brake booster line. Brake booster should run from the base of the carburetor over to the booster with nothing else on it. The PO has not done you any favors.
I agree.
Posting good clear photo of what you have going on so we can see would be a great help so this can get resolved...unless you are happy with it.
The reason I say that is because I have to repair many vacuum line issues when people bring be their Corvettes that have aftermarket stuff on them and it is a total cluster and it needs to be completely re-done and the hoses routed correctly...even if that means I need to buy the correct style vacuum fitting like GM used that goes in the intake to get it all correct again.
Booster goe to intake ,pvc goes to bottom of carb .
UOTE=DUB;1597792030]I agree.
Posting good clear photo of what you have going on so we can see would be a great help so this can get resolved...unless you are happy with it.
The reason I say that is because I have to repair many vacuum line issues when people bring be their Corvettes that have aftermarket stuff on them and it is a total cluster and it needs to be completely re-done and the hoses routed correctly...even if that means I need to buy the correct style vacuum fitting like GM used that goes in the intake to get it all correct again.
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
The RPM air gap has a vacuum fitting location on the rear that you could use for the accessory hoses and leave the carburetor fitting for the brakes so we can get back to your original question about the oil in your vacuum hose. Maybe spreading the vacuum out over the 2 different locations would decrease the oil in the vacuum lines
Thanks for the photos but your camera flash is just not doing its job very well and an additional light source may be needed to get the area brighter.
Also I cannot see where the fitting is in the intake for a possible vacuum fitting..
If your valve covers do not have the baffles...the PCV will suck in oil. Those type of valve covers with no baffle are made for the push in filters and no PCV and are generally not used on a street engine and used for drag racing engines that do not run long and worrying about crankcase pressure are not a huge factor.
We put baffles in baffles in them years ago I had to get the high covers for them to clear the roller rockers . On the pas side there one hookup where the line from the distributor . And on the top there one thats caped . On the drivers side there no ports . In back the pvc goes to port on carb and the rest goes into intake .
08-13-2018, 10:51 AM
booster vacuum question
