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breake question
- Thread starter kkerem
- Start date
cykaaro
NAXJA Forum User
- Location
- ontario, canada
Not sure, but I get the same thing when I brake moderately hard. When I brake really lightly and don't push down too hard, nada. I've not had any braking issues or problems at all though, so haven't worried about it much.
- Location
- Terra Firma
Hello, Kkerem --
Your Cherokee probably has power brakes. The power brakes are operated by engine vacuum. Since you live in Estonia, it is possible that many of the vehicles you have seen from Russia do not have power brakes.
When you step on the pedel, a valve opens in the power booster and allows engine vacuum to assist your foot in applying pressure to the brake master cylinder. You should not hear a loud WHOOOOSH! but a soft little "swish" sound is not abnormal. Also, the vacuum booster should store enough vacuum for a couple of stops even after you turn off the engine, but it can't hold it forever if the vehicle is not driven regularly.
As the vehicle becomes older, the vacuum booster may become less efficient, and the residual (stored) vacuum could be lost overnight. It should hold vacuum overnight, but I have driven cars that don't. When I first got into the car in the morning the pedel would be roick hard, but the brakes wouldn't work because I was pushing against the booster but not really applying pressure to the brakes. As soon as the engine started, I could feel the pedal fall under my foot when the engine produced vacuum. The brakes always functioned when driving, so I didn't worry about it.
Does any of this sound like it is similar to your problem, or does your pedal stay hard even after you have started the engine?
Your Cherokee probably has power brakes. The power brakes are operated by engine vacuum. Since you live in Estonia, it is possible that many of the vehicles you have seen from Russia do not have power brakes.
When you step on the pedel, a valve opens in the power booster and allows engine vacuum to assist your foot in applying pressure to the brake master cylinder. You should not hear a loud WHOOOOSH! but a soft little "swish" sound is not abnormal. Also, the vacuum booster should store enough vacuum for a couple of stops even after you turn off the engine, but it can't hold it forever if the vehicle is not driven regularly.
As the vehicle becomes older, the vacuum booster may become less efficient, and the residual (stored) vacuum could be lost overnight. It should hold vacuum overnight, but I have driven cars that don't. When I first got into the car in the morning the pedel would be roick hard, but the brakes wouldn't work because I was pushing against the booster but not really applying pressure to the brakes. As soon as the engine started, I could feel the pedal fall under my foot when the engine produced vacuum. The brakes always functioned when driving, so I didn't worry about it.
Does any of this sound like it is similar to your problem, or does your pedal stay hard even after you have started the engine?
Thank you for answers. Nice to hear, that people know, where Estonia is located. So, last time I was in Russia more than 15 years ago, or the Estonia was the part of USSR, in that time here wasn't any Jeeps. Here were two models of off-road vehicles: VAZ NIVA and UAZ, both are good on off-road, but... :wierd:
My car is imported from US in 1995...
I know, that the power brakes are “powered” by vacuum. And I hear not very noisy ssssssss, when I brake. The brakes are good, but I haven’t headed that sound before on any cars. My Nissan Almera doesn’t do it :wave:
My car is imported from US in 1995...
I know, that the power brakes are “powered” by vacuum. And I hear not very noisy ssssssss, when I brake. The brakes are good, but I haven’t headed that sound before on any cars. My Nissan Almera doesn’t do it :wave:
might sound silly, but make sure you have vacuum boosted brakes and no ABS (antilock brake system) because that will make some weird sounds when air is trapped in it.
Manually adjust the rear brakes (wheels off the ground and truck blocked so it won't roll away), by turning the starwheel through the inspection hole in the backing plate till the brakes drag, then pry the adjuster forwards and backwards to see if it goes slack again. (this centers the adjuster and shoes, and often gives more slack to be adjusted out) Make sure the rear brakes are working while the wheels are off the ground. I drove my '88 Comanche (XJ style pickup called an MJ) for almost a year with the rear line rotted through and the master cylinder didn't lose a drop of fluid!
If that doesn't cure the situation, then maybe the brake booster's internal valve is worn out or something with a vacuum hose (check the air duct control above the gas pedal to see if the hose came off. You will also get defrost air, but no heat to the floor if it's off) has come loose when you push the pedal.
I don't know if they put the vacuum tank behind the right front bumper, like they did over here, but it gets busted in the slightest of accidents. I replaced all of mine (5 MJs and 7 XJs) with a universal vacuum ball that mounts up on the inner fender on the passenger's side and rerouted the hoses.
Manually adjust the rear brakes (wheels off the ground and truck blocked so it won't roll away), by turning the starwheel through the inspection hole in the backing plate till the brakes drag, then pry the adjuster forwards and backwards to see if it goes slack again. (this centers the adjuster and shoes, and often gives more slack to be adjusted out) Make sure the rear brakes are working while the wheels are off the ground. I drove my '88 Comanche (XJ style pickup called an MJ) for almost a year with the rear line rotted through and the master cylinder didn't lose a drop of fluid!
If that doesn't cure the situation, then maybe the brake booster's internal valve is worn out or something with a vacuum hose (check the air duct control above the gas pedal to see if the hose came off. You will also get defrost air, but no heat to the floor if it's off) has come loose when you push the pedal.
I don't know if they put the vacuum tank behind the right front bumper, like they did over here, but it gets busted in the slightest of accidents. I replaced all of mine (5 MJs and 7 XJs) with a universal vacuum ball that mounts up on the inner fender on the passenger's side and rerouted the hoses.
- Location
- Terra Firma
Is the VAZ the same vehicle as the Lada Niva? I saw many of those in Russia and in Kiev, and I have even seen a few in Chile (South America).kkerem said:
OT
Yes, Lada Niva = VAZ 2121... Now they use only niva. Firstly Niva was only a export name. btw, it is very good offroad car...
Some links, if you are intrested in russian o/r techics
http://www.4wdonline.com/Lada/Lada.html
http://www.carsurvey.org/model_Lada_Niva.html owner reviews
http://www.reviewcentre.com/reviews5148.html -----II-------
something about UAZ too
http://www.4x44u.com/pub/k2/am4x44u/truck_tech/4x_trucks/uaz2.htm
UAZ takes vary much fuel, if the engine isn't "very new" it may take 1L per 1km...
OT off
Yes, Lada Niva = VAZ 2121... Now they use only niva. Firstly Niva was only a export name. btw, it is very good offroad car...
Some links, if you are intrested in russian o/r techics
http://www.4wdonline.com/Lada/Lada.html
http://www.carsurvey.org/model_Lada_Niva.html owner reviews
http://www.reviewcentre.com/reviews5148.html -----II-------
something about UAZ too
http://www.4x44u.com/pub/k2/am4x44u/truck_tech/4x_trucks/uaz2.htm
UAZ takes vary much fuel, if the engine isn't "very new" it may take 1L per 1km...
OT off
red91
NAXJA Forum User
- Location
- exact location unknown
wild pics. Looks like a tiny International Scout.
