| Author | Message | ||
| LOU MURDICA (Loucon)
Rating: N/A |
HOW DO YOU TEST THE JAKE ON A 8V92 MOTOR OFF, TURN SWITCH ON, POWER GOES TO RELAY ON ENGINE BUT PLUNGER DOES NOT MOVE | ||
| Jon W. Rating: N/A |
At idle if you know what wires feed the jake solenoids you can energize them and you will hear the engine lug down. On my coach I had an 8V92 and I could alternately energize each set, and when I energized both simultaneoulsy I could stall the engine. | ||
| Bill Gerrie (Bill_gerrie)
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Lou One way to test it if you do not have an electronic engine is to have the engine running at idle and short out the lockup switch in the transmission momentarily. You will get a loud noise from the exhaust which indicates the Jake is on. Don't do it long. Bill | ||
| Geoff (Geoff)
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Lou-- the plunger will not move in the idle position or with the engine off. The way to check your Jakes is to turn on the engine, but not start it, then turn on the jake. Find the micro-switch on the buffer screw plunger and manually push the microswitch plunger in-- if the jakes work you will hear them clicking under the valve covers. | ||
| Richard Bowyer (Drivingmisslazy)
Rating: N/A |
If you have a wiring diagram it is easy. Find the two wires that go from the last terminal board up thru the valve covers to the Jakes. Using a light duty jumper lead connect 12 volts (or 24 if a 24 volt bus) to each of these two leads one at a time. Only temporarily. You should hear the Jake solenoids energize. If they work from there, just continue back thru all the various components in the electrical path until you find the open circuit. If they do not work on the first test, then you will have to pull the valve covers and find out why not. I did have one solenoid on one Jake go bad and had to replace it. Richard | ||
| Gary Stadler (Boogiethecat)
Rating: N/A |
Lou, From what you posted, I'm not sure what you are trying to accomplish. The Jake solenoids should move, but only a few thousandths of an inch. You can't really see it happen. But if you have reasonable ears, you can go stand near your engine (off) and energize the jake solenoids one by one. They will make a tiny "tick" as you hit them with 12 volts. That said, probably half of the friends I have over 40 and a few young ones can no longer hear this... If it's an electrical problem you're trying to track down, you could hook a marker light or some other small 12 volt lamp across the Jake solenoid and then troubleshoot the system 'till you get the bulb to light up... | ||
| Dale Fleener (Dale_mc8)
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Lou, Jake Brake has an excellent website with many down-loadable documents. You might want to check them out in addition to the great suggestions above. FYI Dale MC8 | ||
| Jon W. Rating: N/A |
Hearing them click with the engine turned off is no substitute for energizing them when the engine is running and you can hear the engine actually lug in response. I could hear them make noise, but they still had failed to function. Running the engine and energizing them eliminates the solenoids as the cause or identifies them as the problem. | ||
| Gary Stadler (Boogiethecat)
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Of course "hearing them click with the engine turned off is no substitute for energizing them when the engine is running" Jon... but Lou needs to troubleshoot the "system"... hearing the solenoids click with the engine off identifies or eliminates the entire electrical side of things as a problem, and it's the first step in "good" troubleshooting. Lou asked a question, did not elaborate on details, and the rest of us are trying to help him figure it out without being there. Give me a break. If we help him eliminate one thing at a time starting from the BEGINNING, he'll figure out what's wrong. Geesh  | ||
| Richard Bowyer (Drivingmisslazy)
Rating: N/A |
Jon, "Running the engine and energizing them eliminates the solenoids as the cause or identifies them as the problem." How? if you are running the engine, you can not hear them energize so you can not eliminate them. Neither can it identify them as a problem if you do not know if they are energizing. Have you ever experienced this exact problem and then did the trouble shooting to determine the exact cause? Failures could include many things such as mis-adjusted buffer switch, defective on-off switch, defective clutch switch, lack of DC power and probably many more items such as an open wire. Good troubleshooting techniques require a systematic procedure that provides you with a go no-go result. Richard | ||
| Jon W. Rating: N/A |
Richard, I had a jake that was not working. In order to find out where and why I did exactly what Gary said. I started from the beginning. The beginning in this case was at the engine. I idled the bus, and when I applied power to the solenoid circuit (there were two) the engine lugged as I posted before. That immediately ruled out the solenoids or the wiring from the junction box to them. Maybe because I am left handed my beginning is at the engine. Maybe right handed people begin at the driver's seat. Either way we are starting at what we perceive as the beginning. Doing what I did was as easy as it could get because it involved some wire and alligator clips. I'm lazy so if I can rule out a source of a problem as simple as that (or identify the problem) I'm all for it. Everything else after that involved tools. | ||
| Richard Bowyer (Drivingmisslazy)
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Jon, That sounds great. The way I read your post I did not understand that. Thanks for the further explaination. Richard | ||
| Gary Stadler (Boogiethecat)
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Agreed. Jon (and everyone)- I find that when I write a post, since I know exactly what's in my mind but I'm basically lazy, I tend to type what seems to be a perfect answer. Then I read it and again, it seems to be a perfect answer. Then I go over it again and read what I've just written, and try to put myself into the place of someone who has no idea what I'm talking about. In that light, I find that since my laziness has usually caused me to skip a lot of words, use terms that I understand but others might not, etc... that my post is actually not very informative and could actually be taken quite poorly by someone who's not inside my head. Same goes for posting questions. It's one thing to say "My jakes don't work, what's wrong" when what you really could have said was "My Jakes don't work but I've checked all the electrical portion of the system and it all functions properly" Posting decent questions about our busses needs just as much attention as posting answers, so that the question asked can get others to think out answers without wasting their time answering about things that really don't matter, simply because the question wasn't thought out as well as it could have been. ......... So Jon, your first answer gave a good quick way to see if Lou's Jakes actually worked but his electrical system did not... but you missed the point of his original question ("motor off"). Then when a few of us tried to answer according to his question, you appeared to scold us a bit by telling us that the best way was to test with the engine running. And the internet makes it way too easy to create reply posts that sound like you're scolding someone when you really don't mean to. I got pissy about being scolded. Richard chimed in. It almost got out of hand. It could all have been avoided by all of us reading a little more closely, thinking a little more about our answers, and re-reading our posts before hitting "that button" to make sure we were coming from a "helping" direction instead of a "hand-swatting" direction. All in all we're here trying to help, and we all have our own ways of doing things (thank heavens). Some ways may be better than others but that's for the reader to decide. Perhaps in the future if we have different suggestions than others, we could put our answers as "here's another way to do it" rather than writing it in a way that could be turned into an arguement... Cheers | ||
| Jon W. Rating: N/A |
Gary, Since I was the first to answer I wasn't questioning anybody's advice. As I read the question Lou was getting power right up to the relay but nothing was happening at the solenoids. If that was the wrong interpretation that is my fault. But, based on my interpretation I offered my original advice so Lou could narrow his search. My second post relating to hearing them click was an attempt to state that hearing the solenoids energize did not necessarily indicate they were functioning, and that with a couple of alligator clips and less than five minutes either isolated or ruled out a whole section of the potential problem area. This meduim is understandibly difficult to hold a debate or discussion in which there are different opinions due to the lag between posting and answers and the lack of seeing the posters face to face. I am not trying to be contentious and maybe trying to keep the answers short is wrong, but I don't see an issue with throwing out an opinion that differs because the ultimate choice of whether to accept the advice or not is Lou's. Absent a post from Lou as to the ultimate solution to the problem I will stand by what I posted, not to be a jerk, but because it still sounds to me that he has verified the circuit from the front right back to the engine, so it sounds like the solenoids are what's left. On my coach I had multiple solenoids so simultaneous multiple failures could be ruled out in the way I described. BTW, I don't take any of this stuff personal unitl someone really goes off the deep end. | ||
| Richard Bowyer (Drivingmisslazy)
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It certainly is nice that you guys are taking the time and trouble to go into some detail in explaining how posts happen and get answered, and how a few on the board really go off the wall if someone questions their answer. Anyhow, all this made me go back and really review the original question which was: "HOW DO YOU TEST THE JAKE ON A 8V92, MOTOR OFF, TURN SWITCH ON,POWER GOES TO RELAY ON ENGINE BUT PLUNGER DOES NOT MOVE". I really do not know what the relay is that he is talking about, but I have to assume it is the final relay in the electrical system that applies power to the Jake solenoids themselves. However he does not indicate if power is going thru the relay to the solenoid. Is the relay actually closing and applying power to the Jakes? Then he states that the plunger does not move. Is this the plunger on one of the solenoids. It sounds like he has the valve cover off and is looking at the Jake solenoids and they (or at least one) is not moving. If this is actually the case, the Jake solenoids are apparently bad and I do not know why he asked the question in the first place. LOL Richard Again, thanks guys for your time and thoughts. | ||
| Geoff (Geoff)
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You guys are something else! If you read my post to Lou I answered the question. "POWER GOES TO RELAY ON ENGINE" means there is electricity to the microswitch, "BUT PLUNGER DOES NOT MOVE" means Lou thinks the buffer pin is supposed to move with the engine off. I told him: "Lou-- the plunger will not move in the idle position or with the engine off. The way to check your Jakes is to turn on the engine, but not start it, then turn on the jake. Find the micro-switch on the buffer screw plunger and manually push the microswitch plunger in-- if the jakes work you will hear them clicking under the valve covers." I have doing this on Jakes for 25 years. Lou may have other problems with his Jakes but he did not elaborate, so offering more troubleshooting tips at this time is pointless. --Geoff '82 RTS AZ | ||
| Richard Bowyer (Drivingmisslazy)
Rating: N/A |
WOW. That is really far out Geoff. Never in my wildest dreams would I have thought he would have been talking about the buffer switch. You get the prize! Richard PS I do not thing Gary or Ron or I were further trying to diagnose Lou's problem. Rather discussing how we all could be more clear in our questions and answers. |