Licensed to kill Posted November 6, 2023 Share Posted November 6, 2023 Trying to figure out what this valve is for. Came off my B-61. Doesn't look like a relay or a QR, ports are too small and not enough of them and I can't think of what else it could do. Anyone recognize this?. Marked "service" on top and "in" on the bottom port that has the cap on its. Quote Link to comment https://www.bigmacktrucks.com/topic/73510-another-name-that-valve-thread/ Share on other sites More sharing options...
doubleclutchinweasel Posted November 6, 2023 Share Posted November 6, 2023 No numbers? Could that be some kind of pressure reducing valve? If you will PM me an email address, I will try to send you some catalogs that might be useful to you...IF the file size isn't too large. 1 Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/73510-another-name-that-valve-thread/#findComment-541545 Share on other sites More sharing options...
doubleclutchinweasel Posted November 6, 2023 Share Posted November 6, 2023 I wondered about an inversion valve, but I've never seen one that looked like that! Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/73510-another-name-that-valve-thread/#findComment-541546 Share on other sites More sharing options...
JoeH Posted November 6, 2023 Share Posted November 6, 2023 Tractor protection valve?... 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73510-another-name-that-valve-thread/#findComment-541552 Share on other sites More sharing options...
doubleclutchinweasel Posted November 6, 2023 Share Posted November 6, 2023 They could have been different back then, couldn’t they? Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/73510-another-name-that-valve-thread/#findComment-541553 Share on other sites More sharing options...
Licensed to kill Posted November 7, 2023 Author Share Posted November 7, 2023 Don't know what an "inversion valve" is, what do they do?. It is not a tractor protection valve, I have that off the same truck. Quote Link to comment https://www.bigmacktrucks.com/topic/73510-another-name-that-valve-thread/#findComment-541556 Share on other sites More sharing options...
mechohaulic Posted November 7, 2023 Share Posted November 7, 2023 1 hour ago, doubleclutchinweasel said: They could have been different back then, couldn’t they? different ;yes =not that different. did you try putting a feed air line to bottom and a controllable air source to side inlet slow increase pressure see if outlet opens at a reduced setting. could be real fancy and install an air gauge on outlet port to check opening pressure or max pressure . Quote Link to comment https://www.bigmacktrucks.com/topic/73510-another-name-that-valve-thread/#findComment-541557 Share on other sites More sharing options...
mechohaulic Posted November 7, 2023 Share Posted November 7, 2023 reread AND enlarged the picture. missed part of in was port having blue cap. was figuring bottom brass port was inlet with control on side blue cap port. would still hoook an airline to in port see what happens. a regulator valve would possibly have an adjustment possible. where was the valve hooked to or near when on the truck. 1/4 air oquipt line would be regulator for whatever. Quote Link to comment https://www.bigmacktrucks.com/topic/73510-another-name-that-valve-thread/#findComment-541558 Share on other sites More sharing options...
JoeH Posted November 7, 2023 Share Posted November 7, 2023 Looks like it says DOT AV30 on it, so google provides an air volume control. Where was it mounted? Did it have lines going anywhere? What was this truck before? Quote Link to comment https://www.bigmacktrucks.com/topic/73510-another-name-that-valve-thread/#findComment-541559 Share on other sites More sharing options...
doubleclutchinweasel Posted November 7, 2023 Share Posted November 7, 2023 22 minutes ago, Licensed to kill said: Don't know what an "inversion valve" is, what do they do?. It is not a tractor protection valve, I have that off the same truck. Inversion valve was a predecessor to spring brakes. If the air pressure dropped, the inversion valve sent air from an emergency reservoir to the parking brake chamber of a DD3 type chamber. I don’t think that’s what it is though. 1 Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/73510-another-name-that-valve-thread/#findComment-541562 Share on other sites More sharing options...
Licensed to kill Posted November 7, 2023 Author Share Posted November 7, 2023 (edited) It came from the truck in my avatar, '59 B-61T. Don't recall where it was mounted for sure but on the frame somewhere midship or near the back IIRC. It was over 2 years ago that I stripped that truck and, of course I did not take enough pictures or label anything. Update, I just went out to the shop and checked, there is no part number on it anywhere, just says "sealco" in an oval across from the "service". I took it and checked where it could have been mounted and asm certain that it was on the back of the cross member that is just in front of the 5th wheel plate, on the drivers side. There are holes in that location that match the bolt size and mount on the valve AND that is where I recall it coming from. Edited November 7, 2023 by Licensed to kill Quote Link to comment https://www.bigmacktrucks.com/topic/73510-another-name-that-valve-thread/#findComment-541563 Share on other sites More sharing options...
Licensed to kill Posted November 7, 2023 Author Share Posted November 7, 2023 I wonder if it could be something like this??. The truck had no spring brakes, just pancake pots. http://www.sealcocvp.com/prod/catalog/110376/index.htm Quote Link to comment https://www.bigmacktrucks.com/topic/73510-another-name-that-valve-thread/#findComment-541564 Share on other sites More sharing options...
JoeH Posted November 7, 2023 Share Posted November 7, 2023 Lol I was reading service upside down, it looked blurry to me. Somehow I got DOT AV30 out of it... I'm going to take another stab and say Holding Valve. Quote Link to comment https://www.bigmacktrucks.com/topic/73510-another-name-that-valve-thread/#findComment-541565 Share on other sites More sharing options...
JoeH Posted November 7, 2023 Share Posted November 7, 2023 Did the truck have wedge brakes originally? Quote Link to comment https://www.bigmacktrucks.com/topic/73510-another-name-that-valve-thread/#findComment-541566 Share on other sites More sharing options...
doubleclutchinweasel Posted November 7, 2023 Share Posted November 7, 2023 LTK, are you going to upgrade the truck to modern spring brakes? If so, you may not need to worry about some of the "old" parts. You can set it up like a more modern piece, and use current valves. I tool the DD3 chambers and inversion valve off my '70, and used piggyback chambers with spring-loaded parking and emergency brakes. What I ended up with was far simpler than what I started out with. Seen lots of B-models with a parking brake valve added to the dash. Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/73510-another-name-that-valve-thread/#findComment-541570 Share on other sites More sharing options...
Licensed to kill Posted November 7, 2023 Author Share Posted November 7, 2023 43 minutes ago, doubleclutchinweasel said: LTK, are you going to upgrade the truck to modern spring brakes? If so, you may not need to worry about some of the "old" parts. You can set it up like a more modern piece, and use current valves. I tool the DD3 chambers and inversion valve off my '70, and used piggyback chambers with spring-loaded parking and emergency brakes. What I ended up with was far simpler than what I started out with. Seen lots of B-models with a parking brake valve added to the dash. Yes I am. MOST of the brake system will be new, I. fact, so far, the only parts that I intend to re-use is the tractor protection valve, governor, manifold, filter (for the shutter stat) and the valves on the dash. I looked in the governor and it looks nice and clean so I will use it but if it causes issues I will just change it out. They are not expensive and this one is mounted on the firewall and easy to access. I am thinking that, since the relays will be mounted on the cross member and will only require maybe 15" - 20" of hose from the chambers that a QR will not be required Quote Link to comment https://www.bigmacktrucks.com/topic/73510-another-name-that-valve-thread/#findComment-541571 Share on other sites More sharing options...
doubleclutchinweasel Posted November 7, 2023 Share Posted November 7, 2023 I have schematics for the later (R) brake plumbing. But, I saw a link to this site that had schematics from people who had already converted their Bs to spring brakes. So, you should have plenty of information at your disposal. The air systems really are not all that complicated once you understand what is being done. You shouldn't have any issues getting it plumbed in and working the way you want. Here is a link to one of them. A Google search will show you others. One think I do encourage in a spring brake setup is the use of an anti-compounding valve to keep from applying the service brake and parking brake at the same time. The way mine was done from the factory was really simple and did not require a separate valve. Mack used a specific push-pull valve for the parking brake which had the exhaust side plumbed in by a small line to the service brakes. This way, if you applied service brakes, that pressure went into the release side of the parking brake and negated some of the spring force. Voila! Anti-compounding! Then, when the parking brakes were released, the exhaust port was closed and the service brakes worked normally. 1 Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/73510-another-name-that-valve-thread/#findComment-541573 Share on other sites More sharing options...
doubleclutchinweasel Posted November 7, 2023 Share Posted November 7, 2023 (edited) Parking Brake Valve with Anti-Compounding Function (one way to do it, anyhow). PP-2.pdf Pretty sure this was it... Edited November 7, 2023 by doubleclutchinweasel 1 Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/73510-another-name-that-valve-thread/#findComment-541574 Share on other sites More sharing options...
h67st Posted November 7, 2023 Share Posted November 7, 2023 2 hours ago, Licensed to kill said: Yes I am. MOST of the brake system will be new, I. fact, so far, the only parts that I intend to re-use is the tractor protection valve, governor, manifold, filter (for the shutter stat) and the valves on the dash. I looked in the governor and it looks nice and clean so I will use it but if it causes issues I will just change it out. They are not expensive and this one is mounted on the firewall and easy to access. I am thinking that, since the relays will be mounted on the cross member and will only require maybe 15" - 20" of hose from the chambers that a QR will not be required I've never seen brakes hooked up without QR valves, I don't know what negatives there would be. I achieved anti-compounding by using a QR-1C valve (not very expensive, very easy to plumb). 1 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73510-another-name-that-valve-thread/#findComment-541577 Share on other sites More sharing options...
Licensed to kill Posted November 7, 2023 Author Share Posted November 7, 2023 15 hours ago, JoeH said: Did the truck have wedge brakes originally? No Quote Link to comment https://www.bigmacktrucks.com/topic/73510-another-name-that-valve-thread/#findComment-541579 Share on other sites More sharing options...
Licensed to kill Posted November 7, 2023 Author Share Posted November 7, 2023 44 minutes ago, h67st said: I've never seen brakes hooked up without QR valves, I don't know what negatives there would be. I achieved anti-compounding by using a QR-1C valve (not very expensive, very easy to plumb). It just seemed to me that the relay acts much like a QR and where the relay would be mounted on the cross member, to go from that to a QR, then to the chambers, the length of hose that needs to be evacuated would be the same if not a few inches longer than going directly from the relay to the chambers. Quote Link to comment https://www.bigmacktrucks.com/topic/73510-another-name-that-valve-thread/#findComment-541580 Share on other sites More sharing options...
doubleclutchinweasel Posted November 7, 2023 Share Posted November 7, 2023 Mine came with QR valves factory. It did not come with relay valves. Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/73510-another-name-that-valve-thread/#findComment-541581 Share on other sites More sharing options...
mechohaulic Posted November 7, 2023 Share Posted November 7, 2023 no QR you may have slow response when releasing the brakes= whole purpose of QR just as it says ==quick release.. total over haul of brake system with all the newer up dated valves it is possible one of the relays/ anti compounding valves may double as QR. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/73510-another-name-that-valve-thread/#findComment-541582 Share on other sites More sharing options...
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