Keeping your next sale ad from reading Newly Rebuilt Engine - Printable Version +- Wanderlodge Gurus - The Member Funded Wanderlodge Forum (http://www.wanderlodgegurus.com) +-- Forum: Yahoo Groups Archive (/forumdisplay.php?fid=61) +--- Forum: WanderlodgeForum (/forumdisplay.php?fid=63) +--- Thread: Keeping your next sale ad from reading Newly Rebuilt Engine (/showthread.php?tid=661) |
Keeping your next sale ad from reading Newly Rebuilt Engine - mrdonut12 - 05-21-2005 11:47 There are far too many coach advertisements with this listed as a positive selling point. The engines in these things are designed to go a lot of miles and there's no reason for this many failures. One simple thing we can all do is the simple cool down after coming off the highway. The turbo charger is a turbine that has 2 sides and a bearing in the middle. The force of the exhaust drives one side and the other side forces more air into the engine. The more exhaust force, the more air is forced into the engine and the more power developed. The bearing in the middle isn't a bearing like we think of one, with little rollers in it. It's a ring of very soft metal that's smooth. The shaft of the turbine is very hard metal and also very smooth. Pressurized oil forced into the gap between the 2 produces a very slick environment and the shaft spins very freely with very little friction. When a very hard metal rubs against a very soft metal with a film of oil in between, very little wear occurs. If both were very hard, wear would be greater. The hot exhaust really heats up the turbine and when you come off the highway and shut off the engine, the oil flow stops and the oil gets cooked in the turbo bearing. When restarted, the oil is gone and severe wear can occur until oil pressure and flow is restored. Little bits of bearing debris are now floating through your oil and engine. So, to protect your engine coming off the highway, cool the engine by downshifting and letting the engine slow you down. Take your time on decel, you're sucking cool air into the engine and cooling off the turbo. If you have a digital pyrometer, you can take the turbo's temperature to see how long of a cool-off cycle it really needs. Even in a non-turbo (or your generator), let the engine run after the load is removed to allow the exhaust valves and parts of the cylinder cool off so you don't bake something. Giving engines a cool down cycle can avoid serious premature engine wear and help them live forever. It's something you need to know. George Witt 81 FC 35 Lincoln, Nebraska--Huskers Keeping your next sale ad from reading Newly Rebuilt Engine - Mike Hohnstein - 05-21-2005 15:27 Good points. I find that 5 minutes at 1000 rpm with the electric fan clutch on cools the engine down real well. It's never a good thing to shut any engine down after highway use with out a short period at idle to allow the exhaust components to normalize a little. Many 454 Chevy exhaust manifolds have had short service life due to lack of cool down after highway running. I put 100k miles on P 30 Chevy motorhomes towing various trailers over the years. Never lost a manifold because I always idled down before shutting the engine off. Mike Hohnstein Mike Hohnstein ----- Original Message ----- From: mrdonut12 To: WanderlodgeForum@yahoogroups.com Sent: Saturday, May 21, 2005 6:47 PM Subject: [WanderlodgeForum] Keeping your next sale ad from reading Newly Rebuilt Engine There are far too many coach advertisements with this listed as a positive selling point. The engines in these things are designed to go a lot of miles and there's no reason for this many failures. One simple thing we can all do is the simple cool down after coming off the highway. The turbo charger is a turbine that has 2 sides and a bearing in the middle. The force of the exhaust drives one side and the other side forces more air into the engine. The more exhaust force, the more air is forced into the engine and the more power developed. The bearing in the middle isn't a bearing like we think of one, with little rollers in it. It's a ring of very soft metal that's smooth. The shaft of the turbine is very hard metal and also very smooth. Pressurized oil forced into the gap between the 2 produces a very slick environment and the shaft spins very freely with very little friction. When a very hard metal rubs against a very soft metal with a film of oil in between, very little wear occurs. If both were very hard, wear would be greater. The hot exhaust really heats up the turbine and when you come off the highway and shut off the engine, the oil flow stops and the oil gets cooked in the turbo bearing. When restarted, the oil is gone and severe wear can occur until oil pressure and flow is restored. Little bits of bearing debris are now floating through your oil and engine. So, to protect your engine coming off the highway, cool the engine by downshifting and letting the engine slow you down. Take your time on decel, you're sucking cool air into the engine and cooling off the turbo. If you have a digital pyrometer, you can take the turbo's temperature to see how long of a cool-off cycle it really needs. Even in a non-turbo (or your generator), let the engine run after the load is removed to allow the exhaust valves and parts of the cylinder cool off so you don't bake something. Giving engines a cool down cycle can avoid serious premature engine wear and help them live forever. It's something you need to know. George Witt 81 FC 35 Lincoln, Nebraska--Huskers ------------------------------------------------------------------------------ Yahoo! Groups Links a.. To visit your group on the web, go to: http://groups.yahoo.com/group/WanderlodgeForum/ b.. To unsubscribe from this group, send an email to: WanderlodgeForum-unsubscribe@yahoogroups.com c.. Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service. [Non-text portions of this message have been removed] |