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81 F100 6 cylinder 300cc

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Old 04-16-2017, 04:03 AM
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Default 81 F100 6 cylinder 300cc

First time posting I apologize if it's in the wrong subforum. I have a 1981 Ford F100 with a 300cc 6 cylinder engine. I was having problems with the starter and flywheel (horrible noise, won't turn over half the time, missing flywheel teeth, etc) and then the clutch completely went out. While everything is torn apart to replace the clutch I am being told I should replace the flywheel also but I just discovered I only have half the money I originally thought for the repair. I have been looking online and see that there is a flywheel ring gear replacement but I can not find anywhere that says which year make or models this option applies to and in asking my mechanically inclined friends none have heard of it before. Can someone please help or lead me in the right direction for the information? My friends all seem to have their own reasons and agendas for stearing me toward their opinions and I just really need the cheapest but effective option. I can not afford a new flywheel and if I can use the ring gear option that would be great but then would I need to have the flywheel machined (sorry not sure of he terminology ) can that be done at home with a sander? If I have to have it machined the new flywheel may have just been cheaper than the gear and the shop.
 
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Old 04-16-2017, 01:05 PM
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Welcome to the site..

A replacement ring gear is usually the way to go, if the flywheel surface isn't heat cracked ( deep heat crack/checking) or full of hot spots (spotty blued-dark areas of heat hardening ) it may be reusable. Its always good to have the flywheel resurfaced/cut but if its not worn (meaning a depressed lip worn 'in to' the flywheel surface from the clutch friction disc) then in a pinch you can break the flywheel glaze with abrasive wheel type work. Post an image if you like..

To change the ring gear an oxy/acet torch with a rosebud or larger heating tip moved/rotated patiently around the ring gear 'flange' surface works well and will eventually expand the ring gears pinch fit and it will drop off. Same on install, gently/steady even heating around the gear will expand and it will fall into place. Once it's cooled, it's locked tight in place. So, may/may not need the help of a machine shop if all checks out, and optional tools available. Starter replacement a must.
 
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Old 05-12-2017, 02:42 PM
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Originally Posted by Hayapower
Welcome to the site..

A replacement ring gear is usually the way to go, if the flywheel surface isn't heat cracked ( deep heat crack/checking) or full of hot spots (spotty blued-dark areas of heat hardening ) it may be reusable. Its always good to have the flywheel resurfaced/cut but if its not worn (meaning a depressed lip worn 'in to' the flywheel surface from the clutch friction disc) then in a pinch you can break the flywheel glaze with abrasive wheel type work. Post an image if you like..

To change the ring gear an oxy/acet torch with a rosebud or larger heating tip moved/rotated patiently around the ring gear 'flange' surface works well and will eventually expand the ring gears pinch fit and it will drop off. Same on install, gently/steady even heating around the gear will expand and it will fall into place. Once it's cooled, it's locked tight in place. So, may/may not need the help of a machine shop if all checks out, and optional tools available. Starter replacement a must.
Thank you so much for the reply sorry for the delayed response. after the flywheel was removed the ring gear now makes much more sense. I am still not sure why nobody I know has heard of that option. the flywheel did have "hot spots" and luckily I was given the money to get the new flywheel. you were so correct about the starter. the teeth were horribly worn down almost non existent and it rattled. So now working on getting another starter. think in about using a used one from a junk yard it can't be any worse than the brand new one that started all this mess. I'm assuming the parts store will not take any responsibility and at least replace the starter seeing that it's been about two years now. Thank you again.
 
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Old 05-14-2017, 12:22 AM
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Originally Posted by Gypsy278
Thank you so much for the reply sorry for the delayed response. after the flywheel was removed the ring gear now makes much more sense. I am still not sure why nobody I know has heard of that option. the flywheel did have "hot spots" and luckily I was given the money to get the new flywheel. you were so correct about the starter. the teeth were horribly worn down almost non existent and it rattled. So now working on getting another starter. think in about using a used one from a junk yard it can't be any worse than the brand new one that started all this mess. I'm assuming the parts store will not take any responsibility and at least replace the starter seeing that it's been about two years now. Thank you again.

Was able to find a used starter and get it installed and the truck still will not move. Maybe you could help troubleshoot before I waste more money I don't have and still don't fix the real problem. Getting it into gear became harder and harder progressively, near the end getting it into 2nd and reverse you had to physically force it and it grinded like crazy but no amount of force would make it go into third or fourth unless it was rolling and also no amount of force would make it go into 2nd if it was rolling. Once you were moving it wasn't too bad as long as you downshifted into second at exactly 4mph (impossible to force it in before or after that speed) , if you missed that downshift the whole mess started over again. Eventually that also got worse and it took more force for second and reverse and downshifting had to happen at about 2mph. Then while driving I tried to put it into third and the shift lever went into position but it acted as if it was in neutral, could not accelerate just coast. the same day lost 2nd and made it home by a hair all the way using 4th. Everyone said clutch so that is what I replaced but now it appears it was the tranny instead. Yes, the clutch would definitely have had to be replaced soon but financially now was not the right time. Now that the new clutch is in when you try to put it into gear and accelerate it will move about half an inch and then the engine completely dies unless you are In 4th gear but driving in fourth all the time is not an option at all. Does this sound like a transmission needing replaced or could their be something else causing this to happen? Thank you for any assistance.
 
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Old 05-14-2017, 09:37 AM
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The clutch should have about 1.5" of "free play" in the clutch pedals travel from the top as you gently push down and feel initial resistance against your foot as the clutch is applied. If there too much free play the clutch won't disengage all the way making for hard/grinding shifts.
Not the only reason, but generally if all shifts are grinding and difficult, clutch drag during shifts may be an issue or checked.

With it in gear, engine running,, and you gently/slowly start to release the clutch, how far off of the floor does the clutch start to engage? Mean the clutch starts to pull or add drag on the clutch?

Not uncommon for syncros to cause grinding shifts, but usually they fail over time, not global fails, more of a noticed grind increase. Shift forks/sliders as well can cause shift concerns.

As a first step, You might take a trans lube sample and look for metal debris. If the clutch is 'fully' disengaging, and shifts are still hard, grind, gear selections 'pop out' or have to be held in by holding resistance against the shift lever,, the trans would cause. A larger amount of debris or suspended metals in the lube may point to a direction...
 
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Old 05-15-2017, 10:54 PM
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Originally Posted by Hayapower
The clutch should have about 1.5" of "free play" in the clutch pedals travel from the top as you gently push down and feel initial resistance against your foot as the clutch is applied. If there too much free play the clutch won't disengage all the way making for hard/grinding shifts.
Not the only reason, but generally if all shifts are grinding and difficult, clutch drag during shifts may be an issue or checked.

With it in gear, engine running,, and you gently/slowly start to release the clutch, how far off of the floor does the clutch start to engage? Mean the clutch starts to pull or add drag on the clutch?

Not uncommon for syncros to cause grinding shifts, but usually they fail over time, not global fails, more of a noticed grind increase. Shift forks/sliders as well can cause shift concerns.

As a first step, You might take a trans lube sample and look for metal debris. If the clutch is 'fully' disengaging, and shifts are still hard, grind, gear selections 'pop out' or have to be held in by holding resistance against the shift lever,, the trans would cause. A larger amount of debris or suspended metals in the lube may point to a direction...
Sorry to keep bothering you but I have a feeling even if proven 100% these two would still deny anything was wrong with the new clutch work. So I had to have the truck moved. Of course had to have my buddy tow it. Interesting thing is while being towed the clutch pedal has to be pushed down the whole time even in neutral. If not pushed the Truck tries to start like neutral is a gear and its being push started. That does not sound normal to me at all. I'm I inaccurate that it is odd for that to happen?
 
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