Clutch Failure, pedal to the floor! |
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Clutch Failure, pedal to the floor! |
mikedsilva |
Apr 17 2015, 05:04 AM
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#1
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Member Group: Members Posts: 90 Joined: 23-February 15 From: Australia Member No.: 18,462 Region Association: Australia and New Zealand |
I'm new to 914 and have no experience with gearboxes...
Tonight, my clutch failed.. the pedal went to the floor. The cable is fine (new)... But turns out that the "fork" the cable is connected to in the gearbox, seems to pivot back and forth freely. The clutch is still engaged but that fork piece doesn't appear to be attached to it. With the basic description I have given, any ideas what it is? Sounds like I will be doing my first gearbox removal... Here is a link to a short vid I just took... https://www.youtube.com/watch?v=F3sahANR2ow |
pilothyer |
Apr 17 2015, 06:49 AM
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#2
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Member Group: Members Posts: 838 Joined: 21-May 08 From: N. Alabama Member No.: 9,080 Region Association: South East States |
Sounds like the clutch cable tube (inside the tunnel) has broken. If you can verify that it has not, you will be removing the transaxle to see what is wrong and it will be fairly easy to see. The clutch cable tube usually breaks free from the weld at the front and then the back at the firewall. Here is a picture of the tunnel (removed and up side down) the tube in question is the largest one in the picture.
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edwin |
Apr 17 2015, 06:53 AM
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#3
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Member Group: Members Posts: 321 Joined: 20-May 09 From: Australia Member No.: 10,384 Region Association: Australia and New Zealand |
Mine had a sheared ball pivot in the bell housing when I got it.
Could also be the pedal roll pin which will drop the cable tension as I remember. Hydraulic is a nice fix if you can get your head around it. |
bandjoey |
Apr 17 2015, 09:44 AM
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#4
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bandjoey Group: Members Posts: 4,926 Joined: 26-September 07 From: Bedford Tx Member No.: 8,156 Region Association: Southwest Region |
(IMG:style_emoticons/default/agree.gif) easy to verify. Pull up the carpet, remove the inspection plates by the shifter, use Hand,mirror and light to find and wiggle the tube. If it moves let us know for further instructions.
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TheCabinetmaker |
Apr 17 2015, 10:01 AM
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#5
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I drive my car everyday Group: Members Posts: 8,301 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
Before you go pulling the trans axle, there are a few thing you can check. First, if the tube breaks loose from the front of the tunnel the pedal does not typically go to the floor. It just feels mushy. Check the roll pin at the pedal cluster. It might have broke. Is so, you can move the pedal while looking at the cable end visible from the front inspection hole. If the pedal moves and the cable does not, you lost the roll pin. Then check the trunnion that the cable goes thru at the clutch fork. I've seen that trunnion break and disappear. If it's Ok, remove the cable from the clutch fork. If it moves from one end of the hole to the other, your ball has broken or the plastic ball cup has dissentigrated.
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SirAndy |
Apr 17 2015, 10:41 AM
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#6
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Resident German Group: Admin Posts: 41,669 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
Mine had a sheared ball pivot in the bell housing when I got it. I've seen this happen too. Time to drop the engine and tranny and get a good look ... (IMG:style_emoticons/default/smash.gif) |
Dave_Darling |
Apr 17 2015, 10:59 AM
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#7
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914 Idiot Group: Members Posts: 14,991 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
(IMG:style_emoticons/default/agree.gif) with Curt (Cabinetmaker). Check the pedal first, because it's less invasive, but realize that odds are better than even that you'll be tearing the trans off the motor soon.
Fortunately that job isn't very hard. --DD |
mikedsilva |
Apr 17 2015, 12:54 PM
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#8
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Member Group: Members Posts: 90 Joined: 23-February 15 From: Australia Member No.: 18,462 Region Association: Australia and New Zealand |
thanks for the replies but we have ascertained it is not the cable or the tube...
It's something in the transmission/clutch itself. i will try to get the transmission out of the car this weekend... |
cwpeden |
Apr 17 2015, 02:04 PM
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#9
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Great White North, huh? Group: Members Posts: 916 Joined: 20-August 06 From: Victoria BC Member No.: 6,693 Region Association: Canada |
Make sure to clean the CV bolt heads well and get the correct socket for them. Its called a triple square, 8mm I think.
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Brian Mifsud |
Apr 17 2015, 02:11 PM
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#10
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Mechanical Engineer Group: Members Posts: 981 Joined: 3-March 03 From: Penngrove, CA Member No.: 384 Region Association: None |
Mine had a sheared ball pivot in the bell housing when I got it. Could also be the pedal roll pin which will drop the cable tension as I remember. Hydraulic is a nice fix if you can get your head around it. Me too... by process of elimination I found the nylon (original) "Socket" that that clutch fork pivots in had split. It was not a metal to metal fit on it's backside when new, in fact had about a 1/8" clearance on it's backside. When the nylon failed, the ball had nowhere to go but the WRONG direction. This amplifies the lack of travel in the RIGHT direction, so I could never fully disengage my clutch even with cable completely tightened up. Dad's lathe and a chunk of bronze fixed that quickly. We machined a replacement that has no clearance behind it, and will outlast the car by lifetimes. No need to go hydraulic on such a wimpy clutch.. we are only managing 80HP! |
mikedsilva |
Apr 17 2015, 03:28 PM
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#11
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Member Group: Members Posts: 90 Joined: 23-February 15 From: Australia Member No.: 18,462 Region Association: Australia and New Zealand |
I updated the first post with a link to a short vid I took with my phone...
Here is the link (i don't know how to embed) https://youtu.be/F3sahANR2ow |
SirAndy |
Apr 17 2015, 03:31 PM
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#12
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Resident German Group: Admin Posts: 41,669 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
(i don't know how to embed) It's in the FAQ subforum: http://www.914world.com/bbs2/index.php?showtopic=97052 (IMG:style_emoticons/default/smile.gif) |
mikedsilva |
Apr 17 2015, 07:40 PM
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#13
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Member Group: Members Posts: 90 Joined: 23-February 15 From: Australia Member No.: 18,462 Region Association: Australia and New Zealand |
(i don't know how to embed) It's in the FAQ subforum: http://www.914world.com/bbs2/index.php?showtopic=97052 (IMG:style_emoticons/default/smile.gif) awesome.. thanks https://www.youtube.com/watch?v=F3sahANR2ow |
euro911 |
Apr 17 2015, 08:42 PM
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#14
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Retired & living the dream. God help me if I wake up! Group: Members Posts: 8,851 Joined: 2-December 06 From: So.Cal. & No.AZ (USA) Member No.: 7,300 Region Association: Southern California |
Yep, you need to pull the transaxle. If you rig or block the rear of the motor, you won't have to remove the motor and all the ancillary connections.
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ThePaintedMan |
Apr 17 2015, 09:33 PM
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#15
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Advanced Member Group: Members Posts: 3,886 Joined: 6-September 11 From: St. Petersburg, FL Member No.: 13,527 Region Association: South East States |
Yep, you need to pull the transaxle. If you rig or block the rear of the motor, you won't have to remove the motor and all the ancillary connections. (IMG:style_emoticons/default/agree.gif) At our Chumpcar race, we had a total clutch friction material failure. Probably because it was a used clutch that sat for awhile, it fell into a million pieces when we pulled the transaxle. The good news is a tranny can be pulled, clutch replaced and reinstalled in ~45 minutes if you have 4 guys who all know what they're doing. Still wish I had videotaped it. We had almost everyone under the car at one point, all tightening one thing or another. (IMG:style_emoticons/default/aktion035.gif) |
mikedsilva |
Apr 18 2015, 11:46 PM
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#16
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Member Group: Members Posts: 90 Joined: 23-February 15 From: Australia Member No.: 18,462 Region Association: Australia and New Zealand |
OK.
Got the trans out of the car easily enough... (the two bolts at the top had me stumped for a while...) Here are some picks of what I found and short video to show the movement soon. I'm too new to transmissions and this is the first I have ever pulled off a car, so I don't what these bits are meant to do... It seems the clutch fork has come off the pin.. but how is this possible?? (IMG:http://www.914world.com/bbs2/uploads_offsite/i1260.photobucket.com-18462-1429422412.1.jpg) (IMG:http://www.914world.com/bbs2/uploads_offsite/i1260.photobucket.com-18462-1429422412.2.jpg) (IMG:http://www.914world.com/bbs2/uploads_offsite/i1260.photobucket.com-18462-1429422412.3.jpg) |
mikedsilva |
Apr 18 2015, 11:50 PM
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#17
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Member Group: Members Posts: 90 Joined: 23-February 15 From: Australia Member No.: 18,462 Region Association: Australia and New Zealand |
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ndfrigi |
Apr 19 2015, 12:02 AM
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#18
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Advanced Member Group: Members Posts: 2,933 Joined: 21-August 11 From: Orange County Member No.: 13,474 Region Association: Southern California |
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euro911 |
Apr 19 2015, 12:28 AM
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#19
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Retired & living the dream. God help me if I wake up! Group: Members Posts: 8,851 Joined: 2-December 06 From: So.Cal. & No.AZ (USA) Member No.: 7,300 Region Association: Southern California |
What's the part # on the lever? Looks like it's not long enough (IMG:style_emoticons/default/popcorn[1].gif)
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Tbrown4x4 |
Apr 19 2015, 01:24 AM
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#20
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Senior Member Group: Members Posts: 704 Joined: 13-May 14 From: Port Orchard, WA Member No.: 17,338 Region Association: None |
Looks like it might have been knocked out of place during installation. Was the transmission or clutch just replaced?
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