I kind of asked but it got lost in another thread. What would cause a 2 way solenoid valve to only work in 1 direction? There is a solenoid on each side but only 1 side works. The solenoid is good but it appears the spool in the valve isn't shifting in the 1 direction because it also doesn't work pushing the manual override pin. Could contamination or maybe a bad o-ring(s) be preventing the spool from shifting in one direction? It was working then got intermittent and then stopped working all together in the 1 direction. The other direction works fine.
You answered your own question. Have you swapped coils on stems to see if it's an open circuit magnet? Have you verified power to the coil? Have you removed the stem and inspected for debris?
It sounds like you're describing a 4 way directional solenoid valve from what you describe with a solenoid on each side that shifts a spool in the center and manual override pins on the solenoid stems. If yes, those valves typically don't have o-rings on the valve spool. If you remove the solenoid stems you should be able to move the spool in the valve back and forth freely. If it does, you've got something wrong with either a solenoid coil or the stem.
I haven't taken the stem off. The valve needs to come off first and it's a bit of pain to remove. When I got the grader the articulation was disconnected and it only had one solenoid coil. I had to destroy that solenoid to get it off. I found new coils and put the valve back on. Success, the articulation worked but it was short lived. Had I known there was an issue other than the coils, I would have taken the stems and spool apart to inspect and clean everything. It worked good both ways but then became intermittent in one direction and then stopped in that direction all together. I found an old brochure on the valve that has the disassembly and assembly instructions. From what I can tell sometimes just cleaning everything will get it working properly. It seems odd it doesn't move even a little in the one direction. In hindsight I'd guess that's why the coil was missing on the valve. I don't think spare parts are available but might be able to get a used valve. Another option would be to use parts from the aux. hyd valve that runs the ripper. It's the same valve body. I don't think it would be too difficult to hook up a different style of solenoid valve to run the ripper.
Solenoid coils are new and I have exchanged the non working side with a coil from the ripper valve. No change but the ripper valve works fine so I know it's not the coil. I noticed the manual override pin pushes in and springs back easier on the working side than the non working side. What I find puzzling is the manual override didn't even attempt to work. This makes me think the spool in the valve isn't moving in one direction but maybe the problem is in the stem?? There are a few o-rings in the stem since it's a wet stem. Another thought was silt lock but would be really weird to have on only one side. Below is a pic. from the manual and a pic. of just one side from an old maintenence paper on the same type of valve.
That's a pretty common arrangement for a 4 way solenoid valve. O-rings only seal external leakage, there are no o-rings on the spool. If items 12 14 15 or 16 are stuck or missing it won't work even with the manual override pins.
Might have some scoring or galling on the spool or in the bore, preventing it from moving one way. I've had decent success (in general, not specifically with your particular valve) with polishing up spools and lightly honing the bores. Takes a bit of time and needs a very thorough cleaning afterwards though.
Number 14 is the manual override pin. It extends out from the end of the tube. It seemed quite a bit harder to push on the side that isn't working but did spring back. I could see the opposite pins move just a tiny bit when pushing the manual overrides. I only tried the one I don't think was working when the grader was running but did both with the machine shut off. It did articulate both ways when I put new coils on. I'm thinking something is preventing the spool from moving past center position in one direction. Edit. Just thought of something. Maybe item 16, the spring retainer, somehow got crooked and jammed in the bore preventing the spool moving.
Would a brake cylinder hone work? I have one from when I did the slave cylinder. Read you should turn it by hand and according to the parts book the spool and valve body are a matched set. Have you repaired valves that wouldn't work one way? I think Jade had a used valve for $400 but maybe mine can be repaired. The other thought was to swap the valve that's controlling the ripper. I'd have to add the optional components the articulation valve uses though. It doesn't look too complicated to take apart and I think a hyd. shop would be a little pricey. I'm sure I could adapt a different valve for the ripper for a lot less than $400 if I went that route. I guess I need to get the valve off and take a close look at it.
Not sure the size of the spool if a brake hone would work. Last one I did I had to slit the end of a 1/2" wooden dowel and wrap the dowel with fine emery cloth. Used a cordless drill to spin the dowel and hone down the rough spot. Bush league I know but when the alternative was a very expensive replacement I think its worth a shot trying to save it.
I did watch a video where a guy just used rolled up very fine sand paper. It would be great if it just needs some touching up. Not so great I have to take it off again. I need to cap the lines better. I lost 2 pails of oil the last time. It was odd because very little leaked when I first took the lines off. I used threaded caplugs but must not have had them tight enough. Steel caps would be better.
I go back to my original comment, remove the coils, remove the solenoid stems, then see if the spool shifts freely. You have to start there. Likewise, you'll then have the other components apart and inspect them. There's a possibility you have a fragment in there that's preventing the spool from shifting, I've seen it more than once.
That's what I'm hoping is wrong and it's easily fixed and/or polished up. Talking with a good hyd's. guy, he said that usually there's not too much that goes wrong since everything has oil around it. The exception is if there was a catastrophic failure of another component or another component is failing and contaminates the whole system. I'd take it to his shop but I think would be quite expensive. It helps I have the R&R procedure for the stems and spool. Is brake clean suitable to use for cleaning the valve body? The R&R manual is from 1975 and says to use trichloroethane which is toxic and not available.
Brake clean is fine, good for cuts too. Joe H
Parts for the stem are available. The tube is listed as an assembly/cartridge with an updated part number but it doesn't list what all it includes. I'm guessing it comes with all the internals because it is a lot more expensive. If it comes complete might be the best way to go if the stems are the problem. Would cost about $250cad. with tax. A little pricey but not too bad if it fixes the problem. If it also needs the rest of the parts would be a little over $400. I have to check my e-mail to see if I got a response regarding what comes in the cartridge kit. When I take the valve apart should I only take apart what's required to fix the problem? Do I need to remove other plugs from the sides of the valves that have no effect on the spool? I don't think the mounting brackets need to be removed. Also is there a good cleaner I could run through the valve that is o-ring safe to clean up any varnish or minor contamination without fully disassembling it? Seafoam has a trans tune product that is supposed to clean up varnish and sticky valves in transmissions and hyd. systems. I could try that but maybe there's something better? I don't want to fully disassemble the complete valve if I don't have to. I think the problem is confined to just the spool not shifting in one direction.
Well, I'm gonna say this again, and I hope it's the last time. Remove the coils from the stems, then remove the stems. Note orientation of any springs or washers as you do this, do it slowly and carefully. Now you can check the movement of the spool with your fingers, it should move back and forth in the valve body freely. If it doesn't, or gets jammed, then you're going to have to go deeper into the valve to find out why. Could be a fragment in the valve, could be a burr caused by a now passed on fragment. But if the spool does move freely, most likely have a problem with coil or stem. Just do it. Until you do you're simply speculating worst case scenarios. You got to dig in and see if you can find a problem and start from there.
I do understand what your saying. I'm hoping to just have to take apart what's necessary to fix the problem. I don't want to take things apart I don't need to or that have no baring on the problem like the mounting brackets or plugs in optional port positions. I was looking for a good cleaner that won't affect o-rings or other seals that aren't taken apart. Best case scenario is I take the suspected bad tube assembly off and the problem is obvious. The spool moves freely indicating the problem is in the tube assembly or there is something preventing the spool from moving or both. I'll have to call to confirm if the tube/cartridge assembly comes complete with all the internal parts. If so I'd replace the whole thing. If everything is seperate is over $400 for all the parts for just 1 side. I was reading excess heat can affect solenoid valve action. Right above the suspected bad tube assembly is a circulating coolant heater that gets hot with the engine running. It hangs about 1-1 1/2" away from the solenoid coil. Could it give off enough heat to affect the operation of the valve? I wouldn't think so but I've seen stranger things.
I have one not working i did some testing on it i should have taken some notes . It was a couple weeks ago and I can't remember . The machine has a bad leak on another hyd thing when i get that fixed i will go back to the solenoid valve problem.
I would change it with the ripper valve if its hard to get at and then disassemble the valve completely, troubleshoot, clean, check& repair and then use it for the ripper
The ripper valve doesn't have the lock valve and a couple other features so if I switched the valves, I'd have to switch the components bolted onto the main valve body. I'm hoping to not have to take that much apart thinking it could create other problems. It is an option though. The articulation valve is kind of a pain to take out but some of the difficulty is because it's hard for me physically. Twisting and bending and crawling under the machine leaves me aching for days and my back already aches a lot. The other issue is getting all the hyd. lines sufficiently capped so I don't lose another 40 litres of oil. I could switch the solenoid stem(s) with one from the ripper valve since I know they work. I was wondering if oil would come pouring out if I removed a solenoid stem? I'm guessing it would since there's no spring to hold the spool centered and there would be some built in leakage to lubricate the spool. I think the problem is in the stem on one side because it was missing a coil when I got the machine. I'm thinking someone took the coil off because it was either faulty or there was a problem with the valve sticking or not working on that side. I may have just got lucky that it worked for a short time when I put a new coil on. Really hoping the problem is with the stem and the plunger is stuck. Then I can just replace the bad parts.
OK, I talked to the service manager at Elvaan/Jade. He said the stems are commonly the problem because of a little dirt or they get a little bent. I did straighten them a little. He said I can just remove the stem. A little oil will come out but it won't gush out. If I left the stem off it would leak a lot over time though. He thinks the stems are ORB threads so I could put a plug on the valve when I remove the stem. He also said I can put the coil on the stem and bench test it to see if the plunger moves. Not having to remove the valve would make it so much easier. If I just have to change a stem/ cartridge would be great and cost about $250. I might not need a new stem and just a couple parts but a complete new stem would give me better piece of mind it will keep working.
I went out today to see what I could figure out. First thing I did is take the wire off what I thought was the good working side. Then I tried the articulation to the side that was working and confirmed it didn't work with the wire off. Great, my suspicions were correct. I took the wire off the other coil and then removed the coil to expose the stem/tube. The stem looked in really good shape on the outside but still had to come off to inspect the internals. It required a 1 1/2" wrench which I didn't have. I had a socket but no way it would work. I had a new 12" crescent wrench to replace a Lost one. It is actually a Crescent brand and the max. opening is 1 1/2". A 15" crescent wrench was too big physically. The 12" turned out to be really good because it couldn't come loose once on the hex. The stem is an ORB fitting but was super tight. I tried hitting the wrench with a hammer but no go. I remembered I had a short piece of rectangular tubing about 16" long. I tried using it as a snipe but the stem wouldn't budge. I had to get creative because there was no way to use a longer snipe/cheater or even a come-a-long on the wrench. I ended up putting a Bessey style F clamp on the tubing and then slid a long aluminum snipe on the F clamp. It took a pretty good push but I did get the stem to pop loose. Then it was a little tricky getting the wrench back on to loosen it enough I could turn it by hand. Thankfully I had a plastic cap the right size to plug the hole. Oil came gushing out initially. It slowed down but was still a steady leak. With the stem out I could inspect it. All the parts of the stem assembly seemed to be in good shape. I cleaned everything and made sure the plunger moved easily using the manual override and inner pin to push it back and forth. The stem in good shape lead me to think the spool was the problem. I couldn't take the spool out of the valve but thought I could try to push it with a ratchet extension to see if it moves. This proved fruitless because once I took the plug out, too much oil was pouring out to fiddle around trying to push the spool. Since the plunger was moving easily in the stem I put it back on. I knew from the ripper valve the manual override pins should be a smooth springy action. The good working side of the articulation valve was but the side I was working on wouldn't push in. Now I knew the spool was stuck one way. I was thinking damn, I need to remove the complete valve afterall to fix the problem. I tried one last time to push the manual override. I was able to use the wooden handle of a hammer against the lower frame to give more leverage on the override pin. On the 2nd try it kind of popped and pushed in. I took the hammer out and tried pushing the pin with my thumb and much to my delight it had the springy action of the other override pins. I tightened the stem up and put the solenoid coil and power wire back on. Then I started the grader and success!! I tried the articulation several times and it was working good in both directions. It was too wet to drive anywhere but I'm pretty confident what ever was causing the spool to stick is no longer an issue. Maybe taking the stem off and having some oil gush out helped dislodge a tiny particle or something?? Anyway it is currently working and I didn't have to remove the whole valve. If it acts up again I'll probably have too but hopefully it's good. I lost less than 2 litres of oil into a drain pan and best of all it didn't cost anything. Maybe this long post could be of help to someone else having problems with solenoid valves on a Champion grader or other equipment.