| Author |
Message |
magoo (Magoo)
Advanced Member
Username: Magoo
Post Number: 3468
Registered: 2-2001
| | Posted on Sunday, November 10, 2002 - 6:05 pm: | |
Greg, I had the same problem with my 308. It sat for a long time in storage and the inline booster valve seized open. I cleaned it with brake clean and there was a great difference in the braking power. Easiest place to start checking. Just a thought |
Greg Rodgers (Joechristmas)
Member
Username: Joechristmas
Post Number: 533
Registered: 3-2001
| | Posted on Saturday, November 09, 2002 - 7:39 pm: | |
Very true. Thanks for the ideas. I will start with the pads. I know that the booster is working but I am not sure if it is working to its optimum potential. I removed the line and there was a huge difference in braking. What type of gauge can you hook up to the vacuum line? Is there an adapter for it? The vacuum gauges I have seen didn't seem to fit or there readings weren't very high. I will change the brake fluid too. |
James Selevan (Jselevan)
Junior Member
Username: Jselevan
Post Number: 216
Registered: 6-2002
| | Posted on Saturday, November 09, 2002 - 7:22 pm: | |
Greg, I am afraid that there are so many variables that it is difficult, if not impossible, to isolate one cause. In the absence of an obvious "weak link" (such as different brake pad material), vacuum system, hydraulics, rotors, all contribute and may differ between the cars.
Jim S. |
Edward Gault (Irfgt)
Intermediate Member
Username: Irfgt
Post Number: 2223
Registered: 2-2001
| | Posted on Saturday, November 09, 2002 - 4:10 pm: | |
Any exhaust restriction will also cause a lower manifold vacuum reading and therefore a harder brake pedal. Make sure there is no cat restriction and also compare manifold vacuum readings between the two cars. |
JRV (Jrvall)
New member
Username: Jrvall
Post Number: 28
Registered: 11-2002
| | Posted on Saturday, November 09, 2002 - 1:42 pm: | |
Vacum to the boosters has been a common problem over the years. You might want to replace the one way check valve in the engine comp. and that the vacum hose is good and of the correct type. Booster vacum hoses are internaly wired with a spring to prevent internal collapse. Also the rubber/flex hoses on all four corners can atrophy (swell up on the inside)from old age/fluid absorbsion preventing the free flow of fluid to & from the calipers. Plus the amount of heat cycles can cure/harden the rotor surface reducing coefficient of friction. I've seen a number of masters cylners go bad to of course. |
Greg Rodgers (Joechristmas)
Member
Username: Joechristmas
Post Number: 531
Registered: 3-2001
| | Posted on Saturday, November 09, 2002 - 9:56 am: | |
Here is what I have noticed. My 78' 308 doesn't stop as well as my QV. My QV stops great and with much less pedal effort where as my 78' takes more pedal effort to get it to stop. Was the stopping power suppose to be better on the QVs? I checked my line to the booster for vac. on the 78' and even disconnected the booster to see if it was working; it is. I thought that the systems were the same so the stopping power should be the same. I am thinking that the 78' may have cheap pads on it too. What do are your thoughts. Has anyone else noticed this. It is a large diff. for example like the clutch pedal effort on a QV vs. a carb 308. Thanks. |