Search Sort Posts:  Oldest to newest Newest to oldest

23/05/2008, 17:30 sweet 17 Joined on 05/08/2006 charente maritime Posts 2,636 Re: no Diesel Thank you, Ron.  I knew there was a catch but I wasn't sure what and I certainly couldn't have explained it to Wooly in a way that he would have accepted!    Report

23/05/2008, 17:47 powerdesal Joined on 07/01/2006 ex-Sharjah U.A.E Posts 2,174 Re: no Diesel  Ron Avery wrote: You can freewheel for short distances without doing any harm to a car or van, but with those old cars the key phrase was this "........but disengaged the gearbox from the axle on the overrun " If you freewheel too much in a short space of time or for too far you will damage the gearbox as it will not lubricate itself and the short term gain could be long term pain ????????????????????????????????????????????????????????????????????????????????? Every gear box I have ever worked on has been partially filled with oil, independently of any other component and has been "splash lubricated", now obviously some hi tech motors have gear box oil pumps but they are, I suspect, not the norm and I suspect the said oil pump is driven by rotation of the gearbox. When you coast or freewheel, the gear box mainshaft is not being driven by the engine, ie in neutral or clutch disengaged. The gear box is of course still connected to the driven wheels via the diff but I am at a loss to understand how a splash lubricated box can be damaged by being turned in its normal direction of rotation. Perhaps you could explain for my further engineering education. Steve now ex-Sharjah + 50 (in France) ...........................................................................    Report

23/05/2008, 18:46 woolybanana'sbrother Joined on 18/01/2008 Posts 1,321 Re: no Diesel I am not an engineer but I would like to ask what happens to an engine when it is idling then? Coasting is just leaving the engine in neutral isn't it? Does this mean that if an engine is in neutral for more than a very short time, the gearbox is getting damaged, at least potentially? Do not try to teach a pig to sing. It wastes your time and annoys the pig.    Report

23/05/2008, 19:47 powerdesal Joined on 07/01/2006 ex-Sharjah U.A.E Posts 2,174 Re: no Diesel Wooly, When a car is in neutral and not moving, the gearbox is not being turned even when the engine is running, or rather the gearbox output shaft is not being turned. The main input shaft is in fact turning but the gears are not selected. When you declutch you physically disconnect the engine from the gearbox allowing the gears to be selected, the synchromesh "cones" spinning up the layshaft to match the mainshast, when the clutch is released the engine drive is "solid " through the gear shafts to the propshaft then the diff then the wheels. When coasting in neutral, the wheels are rotating and driving the diff and hence the propshaft and the layshaft. The mainshaft is, assuming the clutch is not depressed, still being rotated by the engine at low rpm, but not "meshed" with the layshaft. When going back into gear after coasting, the clutch is depressed to take drive away from the mainshaft and allow the synchro to link the main and layshafts. IMHO the lubrication argument is false because the gearbox gear and bearing lubrication is continuous as long as anything is turning in the box because the gears, shafts and bearings are in the oil or are being splash fed. The above is of course a gross simplification given the increasing complexity of modern gearboxes, but is, I believe correct in principle. Steve now ex-Sharjah + 50 (in France) ...........................................................................    Report

23/05/2008, 19:52 ErnieY Joined on 05/12/2006 Nr Prayssac (Lot) Posts 3,740 Re: no Diesel  Ron Avery wrote: If you freewheel too much in a short space of time or for too far you will damage the gearbox as it will not lubricate itself and the short term gain could be long term pain What a load of nonsense Ron, go and hang your head in shame Apart from automatics the one and only car I have ever head of that could potentially have it's gearbox damaged by freewheeling, or rather the equivalent, i.e. being towed without the engine running and turning it or by prolonged coasting, is the Triumph TR7 because it had a pumped oil system, not just immersion/splash.   My doctor said one drink per day, I can live with that !    Report

23/05/2008, 20:10 woolybanana'sbrother Joined on 18/01/2008 Posts 1,321 Re: no Diesel Steve, have you been at the saddiqui or the flash? Not a word do I understand, nor does Ron. Just my gearbox please on a Meriva. Is the thing safe if I slip out of gear? Do not try to teach a pig to sing. It wastes your time and annoys the pig.    Report

23/05/2008, 20:14 powerdesal Joined on 07/01/2006 ex-Sharjah U.A.E Posts 2,174 Re: no Diesel Just the white grenache. Yes, if its a manual box. Steve now ex-Sharjah + 50 (in France) ...........................................................................    Report

23/05/2008, 20:17 woolybanana'sbrother Joined on 18/01/2008 Posts 1,321 Re: no Diesel I fancy a return to the Gulf if they'll have me. Permanently ***. Thanks for the clarification. I shall continue my habit then. Do not try to teach a pig to sing. It wastes your time and annoys the pig.    Report

23/05/2008, 20:24 powerdesal Joined on 07/01/2006 ex-Sharjah U.A.E Posts 2,174 Re: no Diesel I will swap anytime, cant wait to leave.   Steve now ex-Sharjah + 50 (in France) ...........................................................................    Report

Page 4 of 6 (46 items) « First ... < 2 3 4 5 6 >

France Forum » Regions » West » no Diesel

(Quick links) Forums Home |- Search Forums |- Active Topics |- Unanswered Posts User Options |- Sign In |- Join this community |- Forgot Password About This Forum (READ ONLY) |- About This Forum Moving |- Finding/Owning French Property |- Making the Move From Outside the EU |- Long-Term Letting |- Employment Vacancies in France Legal and Finance |- French Legal Issues |- French Finance Building and Renovation |- House Renovations |-- Working with Wood Living |- Earning a Living |- Driving |- French Education |- Pets |- Animal Welfare, Rescue & Protection |- French Satellite TV, French Internet and Telephone |- Health |-- Changes to Healthcare Entitlement, CPAM, CMU and Cartes Vitales |- Swimming Pools in France Owning/Running a Business |- French Artisans |- Gite Owners |- Hotel and Restaurant Owners |- B&B/Chambres d'Hôtes Owners Leisure and Pastimes |- Gardening |- Sport, Leisure and Pastimes |- Shopping |- French Antiques, Arts & Crafts |- Photography |- Motorcycling in France |- Books and Literature |- Getting Married in France |- Pregnancy and Birth French Culture |- French Food and Wine |- French Culture |- French Language |-- French Language FAQs and Useful Links |- Wildlife/Nature/Environment |- French History Travelling to/from France |- Travelling to/from France |- Latest Good Value Deals to/from France Holidays |- Holidays General Discussion |- The Complete France Post Bag |- The Lighter Side |- Other Topics |- Forum Technical Support |- Useful Links About France/French Living Regions |- HOTEL SEARCH |- Central |- North East |- North West |- Paris Ile de France |- South East |- South West |- East |- West |- Corsica and DOM-TOMs