Powerman5K Posted July 31, 2022 Share Posted July 31, 2022 My clutch pedal began sticking about 3/4 of the way after being released. If I put my foot under it and pull up, it will snap back the rest of the way. Any ideas as to what would cause this? Release spring? Bushings? I can't find a replacement spring for an 80' F100. Link to comment Share on other sites More sharing options...
Gary Lewis Posted July 31, 2022 Share Posted July 31, 2022 You probably need to adjust the clutch linkage. But it is also probable that your linkage is worn. Go to Driveline/Clutches & Linkage page and then the Clutch Linkage tab, Mechanical tab, and then the Adjustments And R&R tab for the factory shop manual instructions. Link to comment Share on other sites More sharing options...
Powerman5K Posted July 31, 2022 Author Share Posted July 31, 2022 You probably need to adjust the clutch linkage. But it is also probable that your linkage is worn. Go to Driveline/Clutches & Linkage page and then the Clutch Linkage tab, Mechanical tab, and then the Adjustments And R&R tab for the factory shop manual instructions. So I need to check the Adjusting Rod under the truck by the transmission? If so, am I adjusting it out or in? Link to comment Share on other sites More sharing options...
mat in tn Posted August 1, 2022 Share Posted August 1, 2022 So I need to check the Adjusting Rod under the truck by the transmission? If so, am I adjusting it out or in? don't automatically adjust this. find an assistant if you can. set the brake! engine off! have assistant work the clutch while you thoroughly inspect the workings and the action. there could be a worn or loose pivot ball or even a loose bracket. Link to comment Share on other sites More sharing options...
Ford F834 Posted August 1, 2022 Share Posted August 1, 2022 This may be overly obvious, but check that the return spring is in place and has good tension. This is a HELP! section part if you need another one: Also double check that the spring under the dash is properly seated in the pivot on the cast aluminum pedal box. I have had a failed clutch MC cause incomplete pedal return, but you wouldn’t have a hydraulic clutch in a 1980 unless someone swapped it. Link to comment Share on other sites More sharing options...
Powerman5K Posted August 1, 2022 Author Share Posted August 1, 2022 This may be overly obvious, but check that the return spring is in place and has good tension. This is a HELP! section part if you need another one: Also double check that the spring under the dash is properly seated in the pivot on the cast aluminum pedal box. I have had a failed clutch MC cause incomplete pedal return, but you wouldn’t have a hydraulic clutch in a 1980 unless someone swapped it. I have checked the spring under the dash and it operates normal until it gets to the hangup point. Then if I pull up on the pedal, I can see the spring shift position and the pedal fully decompressed. I'm assuming this should operate smoothly? Link to comment Share on other sites More sharing options...
85lebaront2 Posted August 1, 2022 Share Posted August 1, 2022 I have checked the spring under the dash and it operates normal until it gets to the hangup point. Then if I pull up on the pedal, I can see the spring shift position and the pedal fully decompressed. I'm assuming this should operate smoothly? How much free play (travel before the throwout bearing touches the pressure plate) is there? Too much free play will let the assist spring (the one under the dash) go over center. It is designed to do this to reduce the effort needed to disengage and hold the clutch disengaged. I also agree with the suggestion to fully check the linkage. I had two Fords with mechanical clutch linkages ( both cars) and both developed a crack in the cross shaft (piece from frame to engine) which first gave me a hanging pedal and finally no pedal (push it down and it went "thud" and stayed there). Link to comment Share on other sites More sharing options...
Powerman5K Posted August 1, 2022 Author Share Posted August 1, 2022 How much free play (travel before the throwout bearing touches the pressure plate) is there? Too much free play will let the assist spring (the one under the dash) go over center. It is designed to do this to reduce the effort needed to disengage and hold the clutch disengaged. I also agree with the suggestion to fully check the linkage. I had two Fords with mechanical clutch linkages ( both cars) and both developed a crack in the cross shaft (piece from frame to engine) which first gave me a hanging pedal and finally no pedal (push it down and it went "thud" and stayed there). I checked and there doesn't seem to be any cracks in the linkage. The pedal goes down 1/4 of the was before the clutch engages. It's the same distance I have to pull the pedal up the rest of the way. Link to comment Share on other sites More sharing options...
FuzzFace2 Posted August 1, 2022 Share Posted August 1, 2022 I checked and there doesn't seem to be any cracks in the linkage. The pedal goes down 1/4 of the was before the clutch engages. It's the same distance I have to pull the pedal up the rest of the way. Me 3 on checking the linkage and dont just look at it pull it apart. Remove the rod from the arm at the pedal and look over that end of the rod & arm to make sure they are round. There should also be a thin plastic bushing that fits over the rod before going thru the arm and the pin back in. At the other end of that rod do the same pull it and look it over the same way. There is also a bushing here too. Unbolt the frame pivot for the Zbar or cross shaft and remove the povit and cross shaft. IIRC there are pins you need to pull on the shaft before it can come off the motor side pivot. There should be plastic bushings on both the the frame & motor side pivots. They are held in place with half round spring clips before the bushings can be removed from the pivots. There should also be felt seals that fit on the pivots before the bushings are installed. Make sure all bushings are in good shape. On the Zbar / cross shaft when going back together pack grease in the ends and around the pivots and after you get the frame pivot bolted down push the felt seals into the Zbar / cross shaft. If the Zbar / cross shaft bushings are not kept in good shape they can cock the Zbar / cross shaft and put strain on the motor side screw in pivot and could snap it! You can not get this screw in pivot for the 300 six motor any more. The last one posted from Ebay was $170 IIRC Dont ask how I know all this BTW my pedal was doing the same thing for about 2 weeks before the motor side pivot broke off the motor. I was lucky it happened 1/4 mile from my house and I had a new pivot because I had fixed this one 2 times before. Also when I put the truck on the road 2 years before it had now thin bushings, they were trashed when I pulled it apart for this last fix. I hit the hardware store for thicker bushings in hope they will last longer than 2 years. This is how I got the truck Dave ---- Link to comment Share on other sites More sharing options...
mat in tn Posted August 1, 2022 Share Posted August 1, 2022 Me 3 on checking the linkage and dont just look at it pull it apart. Remove the rod from the arm at the pedal and look over that end of the rod & arm to make sure they are round. There should also be a thin plastic bushing that fits over the rod before going thru the arm and the pin back in. At the other end of that rod do the same pull it and look it over the same way. There is also a bushing here too. Unbolt the frame pivot for the Zbar or cross shaft and remove the povit and cross shaft. IIRC there are pins you need to pull on the shaft before it can come off the motor side pivot. There should be plastic bushings on both the the frame & motor side pivots. They are held in place with half round spring clips before the bushings can be removed from the pivots. There should also be felt seals that fit on the pivots before the bushings are installed. Make sure all bushings are in good shape. On the Zbar / cross shaft when going back together pack grease in the ends and around the pivots and after you get the frame pivot bolted down push the felt seals into the Zbar / cross shaft. If the Zbar / cross shaft bushings are not kept in good shape they can cock the Zbar / cross shaft and put strain on the motor side screw in pivot and could snap it! You can not get this screw in pivot for the 300 six motor any more. The last one posted from Ebay was $170 IIRC Dont ask how I know all this BTW my pedal was doing the same thing for about 2 weeks before the motor side pivot broke off the motor. I was lucky it happened 1/4 mile from my house and I had a new pivot because I had fixed this one 2 times before. Also when I put the truck on the road 2 years before it had now thin bushings, they were trashed when I pulled it apart for this last fix. I hit the hardware store for thicker bushings in hope they will last longer than 2 years. This is how I got the truck Dave ---- wear happens and bad, broken or missing bushings go undetected all too often allowing damaging wear to happen. Link to comment Share on other sites More sharing options...
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