GM proportioning valve reset- must watch!!

Рет қаралды 107,611

Күн бұрын

Пікірлер: 71

@nickgarrett7855 Жыл бұрын

You just answered a question that has plaqued me for over 25 years. My first car had no rear brakes. No matter what I changed or how much money I spent I couldn't get rear breaks. 25 years later and your like heres your problem. Thanks for the video. Ill carry this knowledge with me for the rest of my life.

@RatedR-normal 9 ай бұрын

25 years! I would have went to school just to learn hydraulic components if it took me that long. Haha

@johnpaulgarrett1 2 жыл бұрын

Testing it for ground to see if it is tripped was golden!

@cameronskaggs4188 3 ай бұрын

Wow, there are brains out there. I was doing that last night for 3 1/2 hours trying to figure out why I can’t believe my brakes. I gave you five thumbs up.❤

@williamallen7836 Жыл бұрын

That front "button" is actually the stem of the front metering valve, and is not connected to the shuttle valve. Pressing it will not recenter the shuttle valve. It needs somewhere to go when you press the breaks, and extends outside of the valve body as it opens. The rubber cap just prevents dirt from scoring the stem, and possibly causing a leak. The method to recenter the shuttle valve is to crack the break line open on the opposite side of the original failure. Then have someone use moderate pedal preasure, and hold while you retighten the break line. It's best to remove the light switch first so it doesn't provide any drag on the shuttle valve while recentering it. Then insert the shuttle valve blocking tool, and bleed your breaks. If it won't recenter it's usually because the o-rings on the shuttle valve have hardened. Which causes it to stick. You can try replacing them, but make sure it's a rubber that doesn't break down in break fluid. The shuttle valve can be removed by removing the front metering valve and the read orafice of the proportion valve. The a small brass pin punch can pass through the front metering orafice to knock the shuttle valve out the back of the valve body. If the cup Seals are bad (break fluid will be come out when you remove the warning light switch), I have not been able to find a place to buy them. Which means you are stuck buying a whole new valve. A PV2 type valve will work for most GM break systems. Just make sure you get the correct disk/disk or disk/drum version to match your setup. Hope this helps anyone having difficulty with thier combo valve.

@TheNugler Жыл бұрын

I have a 95 trans am where the proportioning valve is part of the ABS pump. I'm trying to figure out a way to free it up

@larrydriemel6242 Жыл бұрын

William Adam.....you just solved me a problem ! I've been going crazy for 3 days, I read your comment, and there was my answer, don't know how I missed this, "cup seal". , I'm 75yr old retired mechanic and this one went right over my head😅 thank you sir

@williamallen7836 Жыл бұрын

@@larrydriemel6242 lol. Something I learned as a computer tech was, that sometimes a fresh pair of eyes are needed. Eveb if they less experienced. I would be struggling trying to troubleshoot an odd server problem. 5 hours later I would have one my guys who wasn't as good at troubleshooting, but was a hard worker look at it. Less then 2 minutes later he would have the problem pin pointed. It's frustrating at times, but it works. 😂 I learned a lot about the combo valves when I converted my 1968 F100 to front disk brakes. I wasn't comfortable doing it until I knew how they worked so I chose the correct one. So I set out reading every technical document I could on them. An old habit from tech days. Cup seal was the best way I could describe it. I can't recall the technical term for them.

@WesternReloader Жыл бұрын

I just bought a new PV2 for disk/drum, removed the switch to insert to the stop, and I’m concerned the shuttle valve isn’t centered because I see brass that’s about 3/4 of the way filling the void, the gap facing the rubber cap/front side. Is there a way to verify the new prop valve was shipped in it’s centered neutral position, as I don’t want to spend all the time to install, try to bleed, etc, just to removed it to re-set it

@williamallen7836 Жыл бұрын

@@WesternReloader yes. If you put the holding tool in and it seats without issue, it's centered. Basically the way it works is that the center portion of brass shuttle is narrowed. This allows the plunger in the warning switch to extended and open. There's a ramped section to either side of the narrowed center section that pushes the plunger contact closed when one side loses pressure. This grounds the warning light turning it on. If the holding tool can not be screwed in, the shuttle is not centered. BTW no need to crank down on the holding tool. Snug is enough. The solid pin can not be pushed out of the way like the plunger of the warning light can be. This is what keeps the shuttle from moving. Not how tight it is.

@littlefish9670 7 ай бұрын

You're the first video I watched that I can understand. I got a 88 Chevy Silverado and was driving me nuts. Thumbs up thanks a lot for the information. 👍💯🐟👋👋👋👋👋👋😁😁😁😁😁😁

@Canibal_Animal 2 жыл бұрын

Great info! I never knew this in all the years of messing with old GM stuff!

@reginaldbarnes7181 2 ай бұрын

I have a 68 Chrysler Newport with a rear break leak i repaired, and this is my problem solved. Thanks

@ralphfreeman255 10 ай бұрын

Thanks for posting this video and taking the time to explain the functions. Exactly what I'm going through, BUT I purchased a master cyl thinking..... ya know the deal! cheers!

@jjsonsspeedshop4962 2 жыл бұрын

That kind of thing can drive you nuts, thanks for sharing, that’s a great tip. 👍🏻

@martysheets6882 Жыл бұрын

Brother it is very valuable, and thank You for sharing. You're a big help.

@MrVigor47 5 ай бұрын

Man I just went through the heart ache, I ordered a tool and another proportioning valve. Thanks.

@stephencrisci2905 2 жыл бұрын

Omg thank you...yes i have been pulling my hair out..now that almost bald i think i know what to do now..thanx buddy

@kenlelon369 9 ай бұрын

thanks for taking the time

@Kaanggrooviin 9 ай бұрын

Quality info pimpin thank u save me a headache

@UNITED2009100 Ай бұрын

Those ports can become clogged with sediment if you push the caliper pistons back to put on new pads. Some thing with drum brakes, if you push the wheel cylinders back to allow space for the new shoes, you can push sediment back up and into the proportioning valve which can then clog a port or two ports or all the ports. If that happens, the valve can go off center. A leak can cause the valve piston to go off center as well. The switch mounts on the proportioning valve where there is no fluid. It should be dry in that spot. If not the valve is leaking.

@modeljetjuggernaut4864 2 жыл бұрын

Great job man

@readplanet23 8 ай бұрын

Thank You for the informative video. Keep up the good videos. Have A Good Day! 🛻🚚🚛

@Tightwad64 Жыл бұрын

Great video Tks for sharing

@omarvillalobos4876 Жыл бұрын

wow so informative i just converted my rear drum to disc brakes and i just couldn’t get pressure to my rear brakes i was everywhere on forums and went through 3 mechanics who couldn’t find the problem i am hoping this is the problem so i can drive my truck again thank you 🙏

@speedpros 19 күн бұрын

Did you solve your problem and if you did what did you have to do

@donshotrodgarage1717 2 жыл бұрын

Yeah man the them can be a pain to reset once they move! I see that new Hayes Street strip Clutch pressure plate! We need a one around on the bad 55 machine man! Been a while since ive seen it! Have a good one ✌️

@bradleypatrick79 4 ай бұрын

Combination valve with proportioning valve and a fluid pressure differential valve. Which is the shut off valve. Should also trip a light. The proportioning valve keeps rear wheels from locking up during hard braking.

@A_Litre_of_Farva 10 ай бұрын

Here’s some more good info in these magical mystery devices- use a brass one if you can (S-10’s use them), the stock cast iron ones corrode and get gunked up. If you have it off, you can hold it upright and tap it on a hard surface and that should move the valve - if it doesn’t, it’s gunked up inside. Also that switch is your friend, it’ll tell you when something is wrong or if there is air in the system…I don’t know why you’d make in inoperative! Plus you want that shuttle valve to move, if there was ever a leak.

@bahnfire318is 20 күн бұрын

good shit dude, thanks!

@jameslehman85 4 ай бұрын

Thanks very, good information to know.

@ChauncyFatsack Жыл бұрын

Yup I always rip that valve out an plumb it right next to the master cylinder that way it easyer to mess with.I switched from rear drumb brakes to disc brakes and found out the hard way I needed to change to the different proportioning valve after I rolled through an intersection after my emergency break cable snapped.luckily nobody got hurt except my pride lol

@_THE_PIRATES_BOOTY_ Жыл бұрын

Do I need To Do this with a distribution block for 4 wheel drum breaks? 67 camaro RS

@jasonstclair1329 5 ай бұрын

I have recently found that it is utterly impossible to find that switch for the proportioning valve for a 2004 Yukon, not even the dealerships can get it. Insane

@jakeandthedeathlyhallows8284 Жыл бұрын

My man!

@AmatuerOasis 11 ай бұрын

Question, when the low brake fluid sensor is removed, is there supposed to be any pressure or brake fluid in that chamber? I just did a proportion valve rebuild for an 84 Mustang. Different animal, but same function as the proportion valve requires a set screw to hold the internal piston from moving while bleeding brakes. But after my rebuild, my low fluid switch is leaking brake fluid through the top pins. Not the threads. Does that indicate the rebuild wasn't a success? Right now I have the set screw acting as a plug because I cant used the stock low fluid switch. It's possible that when the torched the lines to get them free, they damaged the plastic sensor, but just the same, I was under the impression there wasn't supposed to be fluid under the switch in the chamber where the sensors prong rests in the V groove.

@ronbonick4265 Ай бұрын

great info subscribed

@joshgray1777 2 ай бұрын

Do you have to have the valve off the truck to move the shuttle valve? Or can you move it with it completely mounted? Can’t seem to get mine to move back to center

@belowfray5251 Жыл бұрын

Ira a pisser ain't it. Thanks for sharing

@tonyallers9893 2 ай бұрын

Thanks

@tonycordovatc Жыл бұрын

Bro I'm hoping this is my problem I have a leak coming from that switch every time I press the brake fluid squrts out. Gonna give this a shot

@stevepope5484 Жыл бұрын

So/You tried yours during bleeding the rears? What's good to use/homeaid/to hold it still? A nail and duck tape it down?

@MATMANPRO Жыл бұрын

maybe you could use thick zippy tie or a clamp like a large hose clamp you`d find on a manifold inlet to hold the `nail` down.

@michaeledwards8051 Жыл бұрын

Oh my frickin... THANK YOU! Can I just put a brass plug in the brake light switch spot since I have different gauges and don't have stock warning lights?

@williamallen7836 Жыл бұрын

Yup. The warning light switch is not needed for operation. Just make sure the plug does not extend past the internal threads. This way the combo valve still functions as designed.

@ladariens5732 5 ай бұрын

Anyone know where the proportioning valve is located on a 06 impala 3.9 v6?

@ari1234. 7 ай бұрын

My rear brake line broke and it was fixed and they bleed the brakes...but the light still there..They told me to buy a new valve...If it push that pin with a tester would it reset?

@BeennHurr2330 3 ай бұрын

Close the rear bleeder open the front bleeder and smash the brake pedal to the floor three times did the brake light go out or flicker if yes close the front bleeder and open the rear bleeder and let it gravity bleed until solid fluid comes out of all bleeders

@ericchavez6053 Жыл бұрын

My brake fluid was squirts out of the check valve does this mean I need new proportioning valve or does it need to be reset

@williamallen7836 Жыл бұрын

You either need a new one, or if yours uses standard orings. Just disassemble, clean it, and put in new orings. Basically your orings gave hardened, and developed a flat surface. This allows break fluid to enter ware it shouldn't be. Some older combo valves that use cup seals at either end still have rebuild kits that come with new cup seals. Hope this helps.

@davidcook6038 Жыл бұрын

Could u move it back with air pressue?

@williamallen7836 Жыл бұрын

If you have repaired the leak you want to open the opposite side slightly while someone press the break pedal, and then close it off. If it's stuck, yes removing the valve and using compressed air can sometimes knock it loose. Then double check the orings, and center it before reassembly. Sometimes when they are stuck it's because the orings are toast, and have adhered to the bore surface. So if it's stuck it's just a good idea to replace the orings.

@kingtitan2051 Жыл бұрын

I have 1993 Dakota - same issue..

@chadcaswell67 Жыл бұрын

If you, JB Weld that valve switch, you will disable the ability for your valve to move if you lose brakes on either the front or rear meaning the pin won’t move upward FYI

@jefffedele5002 10 ай бұрын

I thought that was 4 a panic stop...so all the fluid pushes to the front of the car

@leemontoya8028 Жыл бұрын

I just barely touch the brake and the back tires lock up! it's a 60 chev! any idea's?

@williamallen7836 Жыл бұрын

Yup. Couple of possibilities. First inspect your setup to make sure it is still stock, and hasn't been "modified" by a previous owner. If it has, or there are missing comments, decide if you want to replace or upgrade to front disks. If go the upgrade route, don't use an adjustable propotiining valve if you plan on it beibg a steet car. Use a disk\drum combo valve, or a disk\disk combo valve if going with a 4 wheel disk setup. Adjustable propotioning valves are good for the race, but suck on the street. Then I would suspect either bad wheel cylinders that don't retract, or a bad combo valve that is allowing full line pressure to build in the rears.

@leemontoya8028 Жыл бұрын

@@williamallen7836 it's modified it was a two wheel now it's a 4 wheel! friends are telling me sounds like a proportioning valve deal! Thanks!