John Paul Posted July 2, 2009 Share Posted July 2, 2009 i have a 2000 vision 427. My clutch is adjusted, but it suddenly very hard to push the pedal. Any ideas? Quote Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/ Share on other sites More sharing options...
HK Trucking Posted July 2, 2009 Share Posted July 2, 2009 Is the clutch release shaft well greased? (one fitting on each side of the bellhousing).Is the throwout bearing greased?It could be that the clutch cable is at the end of it's lifespan and has lost it's internal lubrication, causing the inner cable to chafe on the outer jacket instead of sliding smoothly. If the clutch cable is doing that, it won't be long until it snaps, because that chafing will cause the inner cable to wear and break. Clutch cables are not greasable, so it would need to be replaced if that is indeed the problem. Quote "If You Can't Shift It Smoothly, You Shouldn't Be Driving It" Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-37604 Share on other sites More sharing options...
Greg Rider Posted July 2, 2009 Share Posted July 2, 2009 Is the clutch release shaft well greased? (one fitting on each side of the bellhousing).Is the throwout bearing greased?It could be that the clutch cable is at the end of it's lifespan and has lost it's internal lubrication, causing the inner cable to chafe on the outer jacket instead of sliding smoothly. If the clutch cable is doing that, it won't be long until it snaps, because that chafing will cause the inner cable to wear and break. Clutch cables are not greasable, so it would need to be replaced if that is indeed the problem.As I am not as familiar with newer trucks I would lean towards the cable. Cars have been using cable operated systems for some time and when it snaps you have no clutch. My actual first thought was spinach and a stair-master! Quote #1 on A-model registryIf I drink because of work, why can't I drink at work? Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-37617 Share on other sites More sharing options...
mopar Posted July 2, 2009 Share Posted July 2, 2009 Along with what HK Trucking has said about the inkages and cable ware, there is also an in cab shaft that should be greased. I would ask Rob for some more advise on that issue. Quote Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-37619 Share on other sites More sharing options...
Rob Posted July 2, 2009 Share Posted July 2, 2009 Along with what HK Trucking has said about the inkages and cable ware, there is also an in cab shaft that should be greased. I would ask Rob for some more advise on that issue.Mopar has hit on a very important point. While you are evaluating both your clutch pedal linkage and cable assemblys ensure the cross shaft bushings that the clutch pedal rides upon have integrity. Some of those are bronze oilite, and some are plastic or nylon. These wear substantially and are relatively easy to replace should they be worn. Before shooting the fittings with grease, shake the pedal from side to side, and in a circular pattern to check these bushings. When the cable is out is the time to service them.If the bushings are let go then the shaft wears on the housing and causes an expensive repair to make work right again.Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-37620 Share on other sites More sharing options...
mopar Posted July 2, 2009 Share Posted July 2, 2009 Mopar has hit on a very important point. While you are evaluating both your clutch pedal linkage and cable assemblys ensure the cross shaft bushings that the clutch pedal rides upon have integrity. Some of those are bronze oilite, and some are plastic or nylon. These wear substantially and are relatively easy to replace should they be worn. Before shooting the fittings with grease, shake the pedal from side to side, and in a circular pattern to check these bushings. When the cable is out is the time to service them.If the bushings are let go then the shaft wears on the housing and causes an expensive repair to make work right again.RobI knew Rob knows some thing about the clutch issue, also I would ask you how much free play dose your clutch pedal and clutch fork has? Quote Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-37642 Share on other sites More sharing options...
John Paul Posted July 3, 2009 Author Share Posted July 3, 2009 I knew Rob knows some thing about the clutch issue, also I would ask you how much free play dose your clutch pedal and clutch fork has? Quote Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-37655 Share on other sites More sharing options...
John Paul Posted July 3, 2009 Author Share Posted July 3, 2009 I disconnected the clutch cable, worked easy. The shaft through bellhousing and throughout is well greased. Still hard to press. Even blew air into clutch assembly, then drenched the clutch and pressure plate with a light oil, still no good result. I'm thinking there may only one other way to find this one. Quote Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-37657 Share on other sites More sharing options...
fjh Posted July 3, 2009 Share Posted July 3, 2009 I disconnected the clutch cable, worked easy. The shaft through bellhousing and throughout is well greased. Still hard to press. Even blew air into clutch assembly, then drenched the clutch and pressure plate with a light oil, still no good result. I'm thinking there may only one other way to find this one.Change the clutch cable!The clutch cables can feel fine with no load on them but once loaded they become stiff. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-37671 Share on other sites More sharing options...
Rob Posted July 3, 2009 Share Posted July 3, 2009 Change the clutch cable!The clutch cables can feel fine with no load on them but once loaded they become stiff.If you have verified that the pedal and linkages are loose and without play in bushings I would change the clutch cable also. FJH is very correct as I've seen that myself that they tighten, (or restrict movement) with a load on them.A 2000 model year truck has had a lot of clutch action over the years.Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-37673 Share on other sites More sharing options...
John Paul Posted July 4, 2009 Author Share Posted July 4, 2009 ok, thanks. i'll replace cable and let you guys know how it turns out. Quote Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-37722 Share on other sites More sharing options...
Rilex Transport Posted November 11, 2019 Share Posted November 11, 2019 Hello John Ricky here.Did you ever fixed your problem with clutch pedal and what was the issue. I have 2008 Mack and clutch is very hard to press. Sometimes goes very smoothly as it should be but in the morning when is cold I have to use alot of power to press. Once is to the floor,goes into gear with no problem. Thank you Quote Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-435694 Share on other sites More sharing options...
JoeH Posted November 13, 2019 Share Posted November 13, 2019 Replace your clutch cable, they fray internally and generate resistance. Quote Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-435810 Share on other sites More sharing options...
david wild Posted November 13, 2019 Share Posted November 13, 2019 NO NO NO the cable will create some drag as it gets worn but if you have a Mack trans your gonna get stiff clutch, done mine twice, works great for couple weeks and goes right back to same crap, all the fuller trans trucks don't seem to have that problem, one more good reason to run a fuller trans. Quote Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-435816 Share on other sites More sharing options...
JoeH Posted November 13, 2019 Share Posted November 13, 2019 I fail to see how a Mack trans can affect the clutch pedal, given that clutches are outside the trans, and you can put whatever brand clutch you want with whatever trans you want. I realize you hate Mack transmissions, but this one stumps me and just smells of irrational prejudice. Replacing trans because the clutch pedal is hard to press is about the dumbest thing I've heard. Rilex, give more info. Is the clutch properly adjusted? Is the clutch brake in good working order? Is the throw out bearing grease? 2 Quote Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-435823 Share on other sites More sharing options...
1965 Posted November 13, 2019 Share Posted November 13, 2019 On 11/11/2019 at 6:45 AM, Rilex Transport said: Hello John Ricky here.Did you ever fixed your problem with clutch pedal and what was the issue. I have 2008 Mack and clutch is very hard to press. Sometimes goes very smoothly as it should be but in the morning when is cold I have to use alot of power to press. Once is to the floor,goes into gear with no problem. Thank you Does it have air assist clutch? Those air cylinders go bad & make them hard to press. If so it’s best to just do away with it & put regular cable on. Did this to my CHU. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-435825 Share on other sites More sharing options...
Mack Technician Posted November 13, 2019 Share Posted November 13, 2019 11 hours ago, david wild said: NO NO NO the cable will create some drag as it gets worn but if you have a Mack trans your gonna get stiff clutch, done mine twice, works great for couple weeks and goes right back to same crap, all the fuller trans trucks don't seem to have that problem, one more good reason to run a fuller trans. Your mother and I didn't raise you to act like this, you learned it somewhere else. On 7/1/2009 at 11:51 PM, John Paul said: i have a 2000 vision 427. My clutch is adjusted, but it suddenly very hard to push the pedal. Any ideas? Mack has forever had issues with stick-slip Phenomenon in the clutch cables. They call it "Phenomenon" because science hasn't been able to cure it or properly/measure/define/predict it. Mack never cure it either. Your nylon surfaces in the clutch cable rub till they become mated. Once they true-up the stick slip starts to kick in. We have it in our wet brake systems, I have to put an additive in to relieve stick slip. Every time you slide your trailer tandem you experience stick-slip. It takes a lot of power to get the slide action to start, but once you break loose it takes less power to move. Install a new cable if it's bugging you. If it's an air clutch system make sure you have the proper updates to keep the weather out of the assist. https://en.wikipedia.org/wiki/Stick-slip_phenomenon Good luck! Quote Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-435826 Share on other sites More sharing options...
david wild Posted November 13, 2019 Share Posted November 13, 2019 we have changed the cable made no difference at all, put new clutch in works great for 2/3 weeks and goes right back to crap, I think it is caused by upside down forks, that is my idea with what is wrong. only mack uses and only our macks have problem. Quote Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-435843 Share on other sites More sharing options...
fjh Posted November 14, 2019 Share Posted November 14, 2019 Nope they bin doing it for yearS like this something else is causing this! Quote Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-435847 Share on other sites More sharing options...
theakerstwo Posted November 14, 2019 Share Posted November 14, 2019 Its not the release fork design. Quote glenn akers Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-435848 Share on other sites More sharing options...
david wild Posted November 14, 2019 Share Posted November 14, 2019 We even used different clutch manf. ???? still like mounted in cement. Quote Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-435860 Share on other sites More sharing options...
JoeH Posted November 14, 2019 Share Posted November 14, 2019 On R models, take the heavy spring hanging from the underside of the dash holding the clutch pedal up. Our spring fell out a few years ago, clutch is way easier to push. R models use 2 return springs, one down by the bellhousing, the other up under the dash. The dash one doesn't do anything critical. Not sure how Rilex's 2008 is set up. Quote Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-435866 Share on other sites More sharing options...
fjh Posted November 14, 2019 Share Posted November 14, 2019 11 hours ago, david wild said: We even used different clutch manf. ???? still like mounted in cement. Are you using the Eaton Easy pedal clutch? If so the clutch needs to be set in this order ! To take advantage of the Over center nature of the easy pedal clutch you likely already know this however I will state it again ! Set the cable so the clutch brake engages RIGHT AT THE FLOOR! THE LAST 1/2 TO 1/4 inch should be CLUTCH BRAKE ONLY! Then adjust your winder inside so that you have the 1/2 inch - 9/16 Gap at the release bearing as required to achieve the necessary 1- 1/2 free pedal in the cab ! If its set this way Then ,I don't have any solutions to your problem other wise I have never ran into the 3 week issue your claiming here Fuller or Mack trans other than a bad cable! And I been at this a fair few years! just sayin! Quote Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-435879 Share on other sites More sharing options...
theakerstwo Posted November 16, 2019 Share Posted November 16, 2019 I added to my superliner and CH a clutch air assist and have no more hard clutch. Only because i have a bad knee.I tryed to post some photos but give up. Quote glenn akers Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-435991 Share on other sites More sharing options...
c-mac Posted November 25, 2019 Share Posted November 25, 2019 If it has the air assist cylinders that will be your problem Quote Link to comment https://www.bigmacktrucks.com/topic/9931-hard-clutch/#findComment-436593 Share on other sites More sharing options...
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