Hey guys, quick question for the experts. This is technically actually for a non-Benz (an old Ford), but I found this forum helpful for my Benz so decided you guys would be good ones to ask. And it's still relevant because it's kind of a generic question.
I have ABS on my car, and I have to replace the proportioning valve. The thing is I only have access to a non-ABS prop valve, as the ABS ones cannot be obtained. I don't think it will be a problem to use, but I want to run it by you guys. I am pretty sure that they are valved the same internally, i.e. the front/rear bias, but the issue is the brake line routing. On the non-ABS the two MC lines go into the prop valve, and four lines go out (It's really two seperate prop valve units; one for the LR/RF circuit and one for RR/LF). The two front lines get full pressure, and the two rear ones are valved to get reduced pressure at a certain point. On the prop valve for an ABS car, only the two rear lines enter the prop valve, and exit it, as the two front lines come out of the ABS and go straight to the wheels. (ABS does not do internal prop. valving on this car.)
So I'm thinking I can simply plug the two outlet ports for the front lines on the non-ABS prop valve, and that should still give the rear lines the correct proportion of valving (instead of two going in and four coming out, two will go in and two will come out.) I'm almost positive this should work without a problem, the only thing I'm thinking is I don't understand exactly how the splitting is done internally inside the prop valve; is it possible that by plugging the outlet for the front line I might cause the rear line to get more pressure than it is supposed to get? I'm assuming that that would NOT happen, because however the rear line is mechanically valved, it should be independent of what is going to the front line. But since the front and rear lines share a common inlet and must split the pressure, I just want to make sure I'm not doing anything stupid. I know it's hard for you guys to say anything for certain without being familiar with the vehicle, but could you give your best guess? Thanks so much!!
Nelson
I have ABS on my car, and I have to replace the proportioning valve. The thing is I only have access to a non-ABS prop valve, as the ABS ones cannot be obtained. I don't think it will be a problem to use, but I want to run it by you guys. I am pretty sure that they are valved the same internally, i.e. the front/rear bias, but the issue is the brake line routing. On the non-ABS the two MC lines go into the prop valve, and four lines go out (It's really two seperate prop valve units; one for the LR/RF circuit and one for RR/LF). The two front lines get full pressure, and the two rear ones are valved to get reduced pressure at a certain point. On the prop valve for an ABS car, only the two rear lines enter the prop valve, and exit it, as the two front lines come out of the ABS and go straight to the wheels. (ABS does not do internal prop. valving on this car.)
So I'm thinking I can simply plug the two outlet ports for the front lines on the non-ABS prop valve, and that should still give the rear lines the correct proportion of valving (instead of two going in and four coming out, two will go in and two will come out.) I'm almost positive this should work without a problem, the only thing I'm thinking is I don't understand exactly how the splitting is done internally inside the prop valve; is it possible that by plugging the outlet for the front line I might cause the rear line to get more pressure than it is supposed to get? I'm assuming that that would NOT happen, because however the rear line is mechanically valved, it should be independent of what is going to the front line. But since the front and rear lines share a common inlet and must split the pressure, I just want to make sure I'm not doing anything stupid. I know it's hard for you guys to say anything for certain without being familiar with the vehicle, but could you give your best guess? Thanks so much!!
Nelson