|
|
Post by the light works on Jul 1, 2015 15:35:04 GMT
I think he means as opposed to sidestapping it to reengage it. I don't know what that means. Is there something different about the way a clutch works on a semi-tractor? sidestepping the clutch, AKA dumping the clutch is when you simply take your foot off of it instead of releasing it slowly. for normal driving in a tractor trailer, once you get moving the third pedal is just there for decoration. |
|
|
|
Post by GTCGreg on Jul 1, 2015 15:46:09 GMT
I don't know what that means. Is there something different about the way a clutch works on a semi-tractor? sidestepping the clutch, AKA dumping the clutch is when you simply take your foot off of it instead of releasing it slowly. for normal driving in a tractor trailer, once you get moving the third pedal is just there for decoration. I see. I've owned cars like that where you only needed the clutch starting out and could easily shift gears without ever touching it again. My Jeep isn't like that. You need to clutch whenever you shift between gears. I thought SD was talking about riding the clutch to control engine RPM while slowing down. My mistake. |
|
|
|
Post by the light works on Jul 1, 2015 15:53:18 GMT
sidestepping the clutch, AKA dumping the clutch is when you simply take your foot off of it instead of releasing it slowly. for normal driving in a tractor trailer, once you get moving the third pedal is just there for decoration. I see. I've owned cars like that where you only needed the clutch starting out and could easily shift gears without ever touching it again. My Jeep isn't like that. You need to clutch whenever you shift between gears. I thought SD was talking about riding the clutch to control engine RPM while slowing down. My mistake. I've only driven one thing where the shift linkage was so funky that it couldn't shift without the clutch, and that was a three-on-the-tree. |
|
|
|
Post by GTCGreg on Jul 1, 2015 16:20:43 GMT
I see. I've owned cars like that where you only needed the clutch starting out and could easily shift gears without ever touching it again. My Jeep isn't like that. You need to clutch whenever you shift between gears. I thought SD was talking about riding the clutch to control engine RPM while slowing down. My mistake. I've only driven one thing where the shift linkage was so funky that it couldn't shift without the clutch, and that was a three-on-the-tree. Well, it CAN be done on my Jeep, but it's not easy. You have to get the engine RPM exactly correct before putting any pressure at all on the stick and then at just the right RPM jam it in. If you miss, it just grinds. I think it may be that the syncros are too worn. It has almost 200K miles on it and the gearbox has never been serviced. |
|
|
|
Post by the light works on Jul 1, 2015 16:37:04 GMT
I've only driven one thing where the shift linkage was so funky that it couldn't shift without the clutch, and that was a three-on-the-tree. Well, it CAN be done on my Jeep, but it's not easy. You have to get the engine RPM exactly correct before putting any pressure at all on the stick and then at just the right RPM jam it in. If you miss, it just grinds. I think it may be that the syncros are too worn. It has almost 200K miles on it and the gearbox has never been serviced. usually, the more worn they are, the easier they engage, because it rounds the corners a bit. |
|
|
|
Post by GTCGreg on Jul 1, 2015 17:08:37 GMT
Well, it CAN be done on my Jeep, but it's not easy. You have to get the engine RPM exactly correct before putting any pressure at all on the stick and then at just the right RPM jam it in. If you miss, it just grinds. I think it may be that the syncros are too worn. It has almost 200K miles on it and the gearbox has never been serviced. usually, the more worn they are, the easier they engage, because it rounds the corners a bit. Are you talking about the synchros or the dogs. The synchros are small rings that engage before the dogs engage to bring the free wheeling gears up to speed. The dogs are supposed to have pointed ends. Maybe the dog ends are flattened out. In the case of my Jeep, probably everything inside the gear box is worn out.  |
|
|
|
Post by the light works on Jul 1, 2015 18:44:57 GMT
usually, the more worn they are, the easier they engage, because it rounds the corners a bit. Are you talking about the synchros or the dogs. The synchros are small rings that engage before the dogs engage to bring the free wheeling gears up to speed. The dogs are supposed to have pointed ends. Maybe the dog ends are flattened out. In the case of my Jeep, probably everything inside the gear box is worn out. what the picture isn't showing is the other side of the synchros have square toothed bits that index into the gears for a positive lock. (assuming yours has a tremec transmission, anyway.) I know this because I used to have the parts for second gear sitting in a box (the shift fork for second in the tremec transmission bends with age and doesn't fully engage second gear - which results in it kicking out of gear when you step off the throttle. it's a quick fix, and for some reason the transmission guy sent the old parts home with me. addendum: the way it is supposed to work is that the synchro freewheels on the shaft. when you select the gear, the idler first engages the synchro, which meshes easily because there is only friction to overcome. then the friction adjusts the speed of the gearset until the synchro indexes to the gear, and then the teeth on the synchro are perfectly aligned with the teeth on the gear. when you grind the gears, either they synchro has indexed without the teeth meshing, or the synchro hasn't indexed so the gear speed isn't matching. (also why heavy transmissions can fight if you try to shift them too fast) |
|
|
|
Post by GTCGreg on Jul 1, 2015 19:09:57 GMT
what the picture isn't showing is the other side of the synchros have square toothed bits that index into the gears for a positive lock. (assuming yours has a tremec transmission, anyway.) I know this because I used to have the parts for second gear sitting in a box (the shift fork for second in the tremec transmission bends with age and doesn't fully engage second gear - which results in it kicking out of gear when you step off the throttle. it's a quick fix, and for some reason the transmission guy sent the old parts home with me. addendum: the way it is supposed to work is that the synchro freewheels on the shaft. when you select the gear, the idler first engages the synchro, which meshes easily because there is only friction to overcome. then the friction adjusts the speed of the gearset until the synchro indexes to the gear, and then the teeth on the synchro are perfectly aligned with the teeth on the gear. when you grind the gears, either they synchro has indexed without the teeth meshing, or the synchro hasn't indexed so the gear speed isn't matching. (also why heavy transmissions can fight if you try to shift them too fast) Good explanation. In the case of my Jeep, some of those parts may be badly worn away or completely gone. Some day, I may have to find out. |
|
|
|
Post by the light works on Jul 1, 2015 19:13:50 GMT
what the picture isn't showing is the other side of the synchros have square toothed bits that index into the gears for a positive lock. (assuming yours has a tremec transmission, anyway.) I know this because I used to have the parts for second gear sitting in a box (the shift fork for second in the tremec transmission bends with age and doesn't fully engage second gear - which results in it kicking out of gear when you step off the throttle. it's a quick fix, and for some reason the transmission guy sent the old parts home with me. addendum: the way it is supposed to work is that the synchro freewheels on the shaft. when you select the gear, the idler first engages the synchro, which meshes easily because there is only friction to overcome. then the friction adjusts the speed of the gearset until the synchro indexes to the gear, and then the teeth on the synchro are perfectly aligned with the teeth on the gear. when you grind the gears, either they synchro has indexed without the teeth meshing, or the synchro hasn't indexed so the gear speed isn't matching. (also why heavy transmissions can fight if you try to shift them too fast) Good explanation. In the case of my Jeep, some of those parts may be badly worn away or completely gone. Some day, I may have to find out. in mine, all the sharp corners you see in the stock photo had been burnished round, plus a little wear on the gear faces from not being fully engaged. - and of course, the shifting fork was sloppy. |
|
|
|
Post by silverdragon on Jul 2, 2015 7:48:05 GMT
Just for interest, I tried a slower-than-idle speed run yesterday.
The engine complained like hell.
Id di NOT like that and shook its self like a wet dog.
|
|
|
|
Post by silverdragon on Jul 2, 2015 7:51:37 GMT
Plus, I have always been taught, USE the damn clutch. Thats what its there for. Slip the clutch under heavy engine braking. Its an art form, for sure,. but I cant be the only one who does that?... Really? That's NOT what it's there for. Engine braking is one thing, Burning up the clutch is a totally different matter. Why would you rather wear the clutch over the brakes? Well, maybe if it's on someone else's truck. Slip the clutch as opposed to (As TLW sort of said) Stomp Snatch Dump and nose-job-on-the-windscreen.... You have to ease it in gently or you snap half-shafts?... It burns no more clutch than a reasonably urgent start up-hill with a load on. |
|
|
|
Post by silverdragon on Jul 2, 2015 8:00:15 GMT
Changing up, roller-skate style, no clutch, if you get out of gear, foot off the loud pedal, push against the next slot gently, the synchro's start to spin up, when the engine revs drop to that of the gear, it will just "pull" its self into gear.
Going down the box, blip the throttle, when revs match the gear should just slide in.
Best practised on an old vehicle you dont mind grinding, and never do that in a hurry, it has to all be done gently.
This is one of the reasons I like driving, its all gentle work, it may be heavy, but there is no need for hurry in a HGV, it gets there when it damn well pleases.
Try telling a cat you are late for a doctors appointment... if you push it too hard your getting the claw in the hurt place. The bigger the cat, the more the hurt....
Its the same in a Heavy, if you push too hard, its going to hurt you in ways you never imagined?...
I drive the equivalent of a disgruntled hungry female Tiger.
|
|
|
|
Post by the light works on Jul 2, 2015 13:52:24 GMT
Changing up, roller-skate style, no clutch, if you get out of gear, foot off the loud pedal, push against the next slot gently, the synchro's start to spin up, when the engine revs drop to that of the gear, it will just "pull" its self into gear. Going down the box, blip the throttle, when revs match the gear should just slide in. Best practised on an old vehicle you dont mind grinding, and never do that in a hurry, it has to all be done gently. This is one of the reasons I like driving, its all gentle work, it may be heavy, but there is no need for hurry in a HGV, it gets there when it damn well pleases. Try telling a cat you are late for a doctors appointment... if you push it too hard your getting the claw in the hurt place. The bigger the cat, the more the hurt.... Its the same in a Heavy, if you push too hard, its going to hurt you in ways you never imagined?... I drive the equivalent of a disgruntled hungry female Tiger. I wish I had footage of me running Tender 23. all of what you just said was out the window. the loud pedal was treated like an on/off switch and shifting went as fast as the flywheel would let it - the only shift that made more than one click was from 6-L to 1-H (which also made a bang when the lever hit the seat) and 5-H to 6-H. of course, the deadline was a little more significant than in HGV driving. |
|
|
|
Post by silverdragon on Jul 3, 2015 6:00:32 GMT
Changing up, roller-skate style, no clutch, if you get out of gear, foot off the loud pedal, push against the next slot gently, the synchro's start to spin up, when the engine revs drop to that of the gear, it will just "pull" its self into gear. Going down the box, blip the throttle, when revs match the gear should just slide in. Best practised on an old vehicle you dont mind grinding, and never do that in a hurry, it has to all be done gently. This is one of the reasons I like driving, its all gentle work, it may be heavy, but there is no need for hurry in a HGV, it gets there when it damn well pleases. Try telling a cat you are late for a doctors appointment... if you push it too hard your getting the claw in the hurt place. The bigger the cat, the more the hurt.... Its the same in a Heavy, if you push too hard, its going to hurt you in ways you never imagined?... I drive the equivalent of a disgruntled hungry female Tiger. I wish I had footage of me running Tender 23. all of what you just said was out the window. the loud pedal was treated like an on/off switch and shifting went as fast as the flywheel would let it - the only shift that made more than one click was from 6-L to 1-H (which also made a bang when the lever hit the seat) and 5-H to 6-H. of course, the deadline was a little more significant than in HGV driving. Rollerskate style, car driving, after the pregnant rollerskate VW beetle nick-name from old, is nothing like driving heavy goods. Gear changes are you pick a slot and snap it in, if it doesnt go in, you have a problem. Heavy goods, the clutch above 2nd gear is just a noise abatement device that sort of quietens down the box as you change gear, (sarcasm...) it doesnt do "much", because if you miss a cog, either you have to "know" and be able to "feel" the engine-gearbox match to get that cog back, or you stop and start again?...(And I have had to do that a few times in my life...) Of course, modern gearboxes are a little easier, especially the indexed sequential automatic ones. The full manual Volvo I drive makes a satisfying click(clack?) when I get the cog right, dunno if that is something mechanical or designed to aid the driver to let him know its in the right slot..... or right in the slot, if you now what I mean?... |
|
|
|
Post by the light works on Jul 3, 2015 14:56:32 GMT
I wish I had footage of me running Tender 23. all of what you just said was out the window. the loud pedal was treated like an on/off switch and shifting went as fast as the flywheel would let it - the only shift that made more than one click was from 6-L to 1-H (which also made a bang when the lever hit the seat) and 5-H to 6-H. of course, the deadline was a little more significant than in HGV driving. Rollerskate style, car driving, after the pregnant rollerskate VW beetle nick-name from old, is nothing like driving heavy goods. Gear changes are you pick a slot and snap it in, if it doesnt go in, you have a problem. Heavy goods, the clutch above 2nd gear is just a noise abatement device that sort of quietens down the box as you change gear, (sarcasm...) it doesnt do "much", because if you miss a cog, either you have to "know" and be able to "feel" the engine-gearbox match to get that cog back, or you stop and start again?...(And I have had to do that a few times in my life...) Of course, modern gearboxes are a little easier, especially the indexed sequential automatic ones. The full manual Volvo I drive makes a satisfying click(clack?) when I get the cog right, dunno if that is something mechanical or designed to aid the driver to let him know its in the right slot..... or right in the slot, if you now what I mean?... 0-60 in T-23 was just under a mile. the volunteer mechanic we had (before the paid mechanics ran him off for getting things done) told me if he got a chance to put the fuel injectors in tune he could cut that in half. I had the shift timing right that I just bounced my foot off the pedal and snapped the stick to shift. but 90% if the time I was quite literally driving it either wide open or coasting - so the only shift I took slow enough for the clicks to be discrete from each other was going to 6th if I got up to speed before I needed to slow down again. |
|
|
|
Post by silverdragon on Jul 4, 2015 6:40:40 GMT
Is that because its always in a hurry (blue's and two's) or just its such a damn slug there was no danger of it ever getting over the speed limit whatever you tried?...
Just asking, because even the lowest powered slug I ever drove on the heavy side was quite capable of being able to cruise on half throttle...
On the lighter side, I gave up trying to drive a fiat thing once because it had zero guts and I was fed up of being a rolling road block.(... thinking on, it may have been a citron?... it wasnt anything fancy, just a ride, cheep, and on borrow until the repairs to mine were finished...)
Micro-Mini economy is one thing, but not daring to go on any road that had a 50mph limit because I know how much I held up people on a 40 limit road, well, how can any [modern] car maker justify that?...
Trucks?..
Yeah, of course, I am aware that heavy goods often has a speed limit 10mph lower than the posted limit above 30mph.
But its not as if the tailgater flashing his lights behind me doing 40 in a 50 limit when I have 40 tons up is going to causer me any concern at all?...
Lug Nuts rule.
If he wants to be a plank, I can roll over him any time, and they will just wipe the paint transfer off the bumpers.
|
|
|
|
Post by the light works on Jul 4, 2015 6:55:30 GMT
Is that because its always in a hurry (blue's and two's) or just its such a damn slug there was no danger of it ever getting over the speed limit whatever you tried?... Just asking, because even the lowest powered slug I ever drove on the heavy side was quite capable of being able to cruise on half throttle... On the lighter side, I gave up trying to drive a fiat thing once because it had zero guts and I was fed up of being a rolling road block.(... thinking on, it may have been a citron?... it wasnt anything fancy, just a ride, cheep, and on borrow until the repairs to mine were finished...) Micro-Mini economy is one thing, but not daring to go on any road that had a 50mph limit because I know how much I held up people on a 40 limit road, well, how can any [modern] car maker justify that?... Trucks?.. Yeah, of course, I am aware that heavy goods often has a speed limit 10mph lower than the posted limit above 30mph. But its not as if the tailgater flashing his lights behind me doing 40 in a 50 limit when I have 40 tons up is going to causer me any concern at all?... Lug Nuts rule. If he wants to be a plank, I can roll over him any time, and they will just wipe the paint transfer off the bumpers. more the slug thing. I did get to make one code three run just before we retired it - but with that mile for 0-60, there were only a few spots where I was at cruising speed for more than a hundred yards or so. - mainly because there were only a few straightaways that long, and it couldn't corner like my work truck. |
|
|
|
Post by silverdragon on Jul 4, 2015 7:00:42 GMT
I have to ask, what was the 60-0 length like?.. did it have any brakes at all, or was it quite good at stopping...
|
|
|
|
Post by the light works on Jul 4, 2015 7:05:36 GMT
I have to ask, what was the 60-0 length like?.. did it have any brakes at all, or was it quite good at stopping... well, it was a bit iffy running empty... but yes, they did s better job tuning the brakes than the engine. of course, you'd offload a few gallons of water in the process. |
|
|
|
Post by silverdragon on Jul 4, 2015 7:24:42 GMT
I have to ask, what was the 60-0 length like?.. did it have any brakes at all, or was it quite good at stopping... well, it was a bit iffy running empty... but yes, they did s better job tuning the brakes than the engine. of course, you'd offload a few gallons of water in the process. Wear a raincoat whilst driving?... |
|
