pigdog Posted February 8, 2011 Share Posted February 8, 2011 After owning the Ferret for a while now I would like to check in and see if I'm driving it correctly. I have been changing up to the next gear at around 3500 RPM's I hold the GCP down long enough for the RPM's to drop a bit then let it out. On changing down I wait till about 1500 RPM's and hold the GCP down, blip the gas to bring the RPM's up then let out the GCP. I wanted to know if this is correct. -Chris 1965 Mk 2/3 Ferret 00 EC 55 Quote Link to comment Share on other sites More sharing options...
0 sirhc Posted February 8, 2011 Share Posted February 8, 2011 Chris, It sounds like you are slipping the GCP. Remember you can not use it like a clutch. Once you have pressed it down, you must let it back up straight away. Chris Quote Link to comment Share on other sites More sharing options...
0 griff66 Posted February 8, 2011 Share Posted February 8, 2011 (edited) must have to disagree having read the manuals you are meant to match revs between gears holding pedal fully down and increasing revs or otherwise is not slipping gear change if your doing it right its nice smooth changes by slipping they mean gear change pedal half up etc brake band fully disengaged or fully engaged.. Edited February 8, 2011 by griff66 Quote Link to comment Share on other sites More sharing options...
0 oily Posted February 9, 2011 Share Posted February 9, 2011 ...I drive a saracen, similar gearchange system,.... should be no real need to blip throttle, when changing gear up or down, a smooth change from one gear to the next with no jerks, is what you are aiming for, and as already stated GCP, is pressed hard down and released instantly..... in fact in the manual it actually states that it is quite acceptable to change gear at full throttle when moving about off-road, I have tried it, -out of curiosity, more than necessity, and yes it works!, but I was wary of doing it! Quote Link to comment Share on other sites More sharing options...
0 griff66 Posted February 9, 2011 Share Posted February 9, 2011 from user hanbook 12174 page 119 to change gear ,move the selector lever to the next higher or lower position .when the engine has reached the appropriate speed,press gear ghange pedalas far as it will go,and release.when changing up a pause must be made with the pedal fully down while the engine is decelerated. if changing down,the engine must be accelerated by maintaining pressure on the accelerater.do not at any time pump/blip the the throttle whist changing gear .change up speed 3500 rpm,change down 2000 to 2500 rpm.. Quote Link to comment Share on other sites More sharing options...
0 AlienFTM Posted February 9, 2011 Share Posted February 9, 2011 (edited) ...I drive a saracen, similar gearchange system,.... should be no real need to blip throttle, when changing gear up or down, a smooth change from one gear to the next with no jerks, is what you are aiming for, and as already stated GCP, is pressed hard down and released instantly..... in fact in the manual it actually states that it is quite acceptable to change gear at full throttle when moving about off-road, I have tried it, -out of curiosity, more than necessity, and yes it works!, but I was wary of doing it! These guys are right. It doesn't matter how hard or quick you smack the GCP (ok it does: make it happen fast and hard!), that's the right way to do it. The fluid flywheel entirely governs the smoothness of the change so pratting about with the GCP gains you exactly nothing and loses you plenty cos that's not how it is designed. As to changing gear at full revs, yes. I was taught this by the RNZAC instructor who had to do me a three-day Ferret driver course before we went to UNFICYP because UNFICYP needed to know we had been trained, even though I had been driving them in NI prior to this (didn't need training: covered by a Group B licence, an automatic car, which came as a freeby when I passed Group A, a manual car). He pointed out that taking the foot off the throttle to change down going up a hill only allowed the revs to drop off, then you had to wind them back up or you'd find yourself having to change down more gears than if you simply preselected and kicked the GCP. The UN outpost at Skouriotissa was in a mine engineer's bungalow. To get out of the site onto the Green Line, we had to drive up a spoil heap. Changing down at full revs made all the difference, trust me. Most of my RAC career was spent in Ferrets. Trust me. Edited February 9, 2011 by AlienFTM Typo Quote Link to comment Share on other sites More sharing options...
0 griff66 Posted February 9, 2011 Share Posted February 9, 2011 (edited) HHMMMM guess the manuals incorrect eh?? if your driving it correctly there will be smooth changes no jerking of drivetrain etc if gcp is fully down u are not slipping the breakbands ,possibly its best to read the manuals understand them and make up your own mind! (i have driven company vehicles and they never had the easiest life! dare i suggest that some army drivers were not overly concerned with gear box longevity!!!) by the way at high rpm fluid flywheel only has 2 percent slip so at 3000rpm going from high gear to next lower with out letting road speed/rpm decay will be asking a awfull lot of a brake band/drive train !! Edited February 9, 2011 by griff66 Quote Link to comment Share on other sites More sharing options...
0 John Pearson Posted February 9, 2011 Share Posted February 9, 2011 (edited) The fluid flywheel entirely governs the smoothness of the change so pratting about with the GCP gains you exactly nothing and loses you plenty cos that's not how it is designed. . Gearchanges (both ways) take place at a minimum of 2000rpm? But if the engine (ie flywheel) is rotating at 800rpm plus then there is only 2% slip (ie almost locked up) so ALL of the slip necessary to engage different speeds of flywheel and gearbox input shaft comes from the slipping engagement of the relative gear's brake band. If you change down, leaving your foot on the gas (eg hillclimbing and the gear is too high for the slope) then good fast timing with the GCP enables the engine to speed up to match the new gearbox input shaft speed and gives a smooth change. Why would you need to keep your foot on the gas when changing up? The engine needs to slow down and it will do so, either by you releasing the gas momentarily or by extra slip and wear on the gear brake band as the vehicle's inertia slows down the engine for you. By revving the nuts out of it when changing up may give a momentary 'boost' as the extra rotational momentum of the speeding engine is brought down to the correct gear engagement speed and that might be useful in special circumstances (providing a fleeting target, going through a short length of sand or mud for example) but it will be at the cost of your gear brake band linings, universal joint wear and possible bevel gear breakage. The operational techniques taught in the past when the Government were paying the repair bills have little relevance to preserving machinery for future generations, surely? Sorry Griff 66: did not realise I was duplicating your post. Edited February 9, 2011 by John Pearson typo! Quote Link to comment Share on other sites More sharing options...
0 griff66 Posted February 9, 2011 Share Posted February 9, 2011 (edited) agreed, think people get a bit caught up in the :its not a clutch: syndrome what i think they mean by that is gcp half up and increasing revs thats a no no ! its aknack to get every change spot on no jerking but v satisfying when u do as every private ferret owner knows sometimes it all comes together and other times your glad to park up!:cool2: yes no need to keep foot on gas when changing up u want rpm to decrease Edited February 9, 2011 by griff66 Quote Link to comment Share on other sites More sharing options...
0 ferrettkitt Posted February 9, 2011 Share Posted February 9, 2011 The gear change pedal bit has to be mentioned to new owners and reading the manual for the correct way of changing gear is a must. Treat a GCP like a clutch and you will wear out the brake bands. Then you have the joy of pulling the box out to replace the bands Quote Link to comment Share on other sites More sharing options...
0 oily Posted February 10, 2011 Share Posted February 10, 2011 ... gearbox change/repair on a Ferret....-not a nice job, agreed! .... fancy trying it on a Saracen?..... I hope I never have to do it on mine!:shake::angry:sweat: Quote Link to comment Share on other sites More sharing options...
0 griff66 Posted February 10, 2011 Share Posted February 10, 2011 just in cost u have got to be looking at well over a grand for gearbox thats if u can find one! treat em gently!!! Quote Link to comment Share on other sites More sharing options...
0 oily Posted February 10, 2011 Share Posted February 10, 2011 ...I already snapped up a new old-stock one in a crate for £750, about a year ago, seems the problem was the flywheel leaking, intermittently (ie, when it got a tad warm....).... looks like I've found a source for new flywheels now, amongst other parts! Quote Link to comment Share on other sites More sharing options...
0 griff66 Posted February 10, 2011 Share Posted February 10, 2011 good price if nos i know certain places want a lot more than that and getting much harder to find its not what you know its who you know!!!:-D Quote Link to comment Share on other sites More sharing options...
0 ferrettkitt Posted February 10, 2011 Share Posted February 10, 2011 just in cost u have got to be looking at well over a grand for gearbox thats if u can find one! treat em gently!!! Cheaper to buy the bands rather than replace the gearbox Ahem I found one Quote Link to comment Share on other sites More sharing options...
0 AlienFTM Posted February 10, 2011 Share Posted February 10, 2011 Why would you need to keep your foot on the gas when changing up? Did the original comment read "change up"? (Can't be bothered to go back and check.) If so my reply is completely wrong. I read "change down". No you wouldn't want to keep revs on while changing up. Quote Link to comment Share on other sites More sharing options...
0 AlienFTM Posted February 10, 2011 Share Posted February 10, 2011 ... in fact in the manual it actually states that it is quite acceptable to change gear at full throttle when moving about off-road! No the original post didn't mention changing up, and neither did mine. I guess it also doesn't specify changing down. My reply did. One other thing. Driving Ferret and Saracen in the real world under load, if you start being gentle with the GCP, you'll end up one day with your left knee in your face and a Ferret (or worse a Saracen) stuck in a false neutral bombing down the road and the force required to operate the GCP is incredible. Not a good time to be bombing along and out of gear. No, it never happened to me personally, because I was taught always to give it a good kick and it worked. But it happened to enough of my friends. Quote Link to comment Share on other sites More sharing options...
0 griff66 Posted February 10, 2011 Share Posted February 10, 2011 (edited) well the real world for ferrets now is private ownership ,and i have had gcp kick back and its got a bit of force to it buts not like it forces your knee into your chops !!!9 nobody is talking about being gentle with gcp quick down quick up but there can be pause at bottom of travel Edited February 10, 2011 by griff66 Quote Link to comment Share on other sites More sharing options...
0 oily Posted February 11, 2011 Share Posted February 11, 2011 No the original post didn't mention changing up, and neither did mine. I guess it also doesn't specify changing down. My reply did. One other thing. Driving Ferret and Saracen in the real world under load, if you start being gentle with the GCP, you'll end up one day with your left knee in your face and a Ferret (or worse a Saracen) stuck in a false neutral bombing down the road and the force required to operate the GCP is incredible. Not a good time to be bombing along and out of gear. No, it never happened to me personally, because I was taught always to give it a good kick and it worked. But it happened to enough of my friends. I can vouch for this in my early driving attempts, yes it does take you by suprise and can be very painful,... it's something you tend not to repeat if possible!:cry: Quote Link to comment Share on other sites More sharing options...
Question
pigdog
After owning the Ferret for a while now I would like to check in and see if I'm driving it correctly.
I have been changing up to the next gear at around 3500 RPM's I hold the GCP down long enough for the RPM's to drop a bit then let it out.
On changing down I wait till about 1500 RPM's and hold the GCP down, blip the gas to bring the RPM's up then let out the GCP.
I wanted to know if this is correct.
-Chris
1965 Mk 2/3 Ferret
00 EC 55
Link to comment
Share on other sites
18 answers to this question
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.