FUEL $$$ WTF

[W2PFY]

I drive an old clunker 93 Saturine. I did all that free wheeling for about a month coasting on long hills and such. I did not ever turn off the engine for fear that my steering wheel would lock up. I did not see any significant difference in MPG.

It gets about 35 MPG on trips and around 30 in city. 

[k4kyv]

I have noticed that simply putting the vehicle in neutral at a light makes a difference. 

When driving a manual shift I always throw it in neutral at a light or other lengthy stop. It saves wear and tear on the throw-out bearing as well as on the hip and knee joints when you don't sit there and hold down the clutch for extended periods of time. Once you develop the habit, you do it without even thinking. I find it much easier, the "lazy" way. But I wouldn't think it would make an iota of difference in idling speed or fuel economy, since idling in neutral only involves overcoming the friction of the bearings in the the gear box itself vs the the friction in the throw-out bearing when holding the clutch down. Since you have to shift all  the way back down to the bottom before taking off anyway, it makes perfect sense to go half way (to neutral) while you are stopped at the light. But still, I don't see how that would cause the idle speed to drop.

[The Slab Bacon]

i wasn't clear; sorry about that.  when I said I take the car out of gear I wasn't exactly correct--I leave it in gear but push in on the clutch pedal so it isn't engaged.  I don't put it in neutral except when sitting at a red light on level ground.

IIRC, that's called "Georgia Overdrive"   


Ya know for always driving a stick, I never do that for some odd reason  
I drive a '99 Ferd Ranger with a 2.5. I get 26 or 27 mpg around town, and well over 30+ on the highway. (I do use mid grade gas) No one else that I know with one of those gets that kind of mileage. I guess I just got a light foot. With that kind of mileage and the little bit of driving I do, I havent felt the pain too badly yet. However those $45+ fill ups do cause me to roll an eyebrow!!

[k4kyv]

I think freewheeling is illegal in this state too.  They claim it is dangerous because you are relying totally on the brakes without the benefit of the engine's braking action when you take the foot off the gas.  I'm not sure if just pressing in on the clutch would be considered freewheeling and besides, it would be hard to determine if someone was driving along with the clutch in.

I remember in Addis Ababa, Ethiopia, they used little Fiat taxis all over the place, and there were some long hills. You could ride the taxis for the equivalent of something like 16 cents US, so that's how everyone moved about.  The drivers not only put the cars in neutral; they turned off the ignition during the coast. When they finally arrived near the bottom of the hill, they would put it back in gear and turn on the ignition, and the engine would start back up again. Every driver I rode with during my visit there did it.

I think some cars back in the 30s and 40s had a freewheeling feature that worked simply by engaging a lever, and more accidents resulted.  But I doubt it is  really any safety hazard with to-days automotive and brake technology. Of course, with some cars, if you turn off the ignition the steering locks up - not good.

I have been known to "freewheel" in my van with automatic transmission when trying to track down line noise.  The damn thing puts out so much garbage in the radio spectrum with the engine running that it masks the noise I am trying to track down. So I'll just speed up to maximum safe speed, put it in neutral, cut off the ignition, and let it coast while listening with no RFI from the car's electronics.  Other drivers probably think I am having car trouble.

[flintstone mop]

i wasn't clear; sorry about that.  when I said I take the car out of gear I wasn't exactly correct--I leave it in gear but push in on the clutch pedal so it isn't engaged.  I don't put it in neutral except when sitting at a red light on level ground.

OK Rob now another tangle of webs. You will wear out the throw-out bearing on the clutch faster by constantly depressing the clutch pedal for free-wheeling.
The manual transmission in your vehicle should give you an advantage over the rest of us for increased gas mileage. If you're really innovative, install a two-speed rear end and change the gear ratios. When you're tooling along on the highway at 70MPH the RPM's would be at 1500 in your highest gear.
Fred

[W7TFO]

"When you're tooling along on the highway at 70MPH the RPM's would be at 1500 in your highest gear.
Fred"


A way to figure a gear ratio change for the best mileage is to find and/or plot the engines' torque curve (not HP), and set the gears for that peak: RPM=70 MPH (or whatever).  

This usually coincides with the highest manifold vacuum reading (gas powered rigs) whilst on the highway...but maybe not the speed you want to be going.

73DG

[W2PFY]

The old Saab cars had an automatic free wheeling system. You could set it up IIRC with a leaver inside the car. The mechanism inside the front wheels used needle bearings that were about 1/16 diameter and about two inches long. When you got done free wheeling, you just put the gas to it and the thing would re-engage with a clunking sound. As these bearings became worn, they would lock up and you had to tear the whole system apart to repair it.

I was advised by my mechanic not to use the system on my Slob. It was one of the earlier millage extenders that I know of.

  

[K3ZS]

A new mileage extender is in the works.   An engine that shuts off when you are stopped, just like with the hybrids.   It requires a different type of starter.  Think of all the gas burning while a zillion cars are stuck in traffic everyday.

[W3SLK]

Bob said:

A new mileage extender is in the works.   An engine that shuts off when you are stopped, just like with the hybrids.

Aint nothing new there. They've been using them on golf carts for years. 

[K5UJ]

i wasn't clear; sorry about that.  when I said I take the car out of gear I wasn't exactly correct--I leave it in gear but push in on the clutch pedal so it isn't engaged.  I don't put it in neutral except when sitting at a red light on level ground.

OK Rob now another tangle of webs. You will wear out the throw-out bearing on the clutch faster by constantly depressing the clutch pedal for free-wheeling.

Well, I have to admit I did some checking on this, over on a car forum, and the experts agree with you Fred.  What a fool I was to doubt the wisdom of amfone.net 

[k4kyv]

A new mileage extender is in the works.   An engine that shuts off when you are stopped, just like with the hybrids.   It requires a different type of starter.  Think of all the gas burning while a zillion cars are stuck in traffic everyday.

But that adds wear and tear on the solenoid, battery and starter motor. Plus, it becomes a PITA when the engine gets a little age on in and becomes harder to start. You can't win for losing.

I disconnected the seat switch on my riding lawn mower that killed the engine whenever I got out of the seat for any  reason, even to toss something out of the way to keep from running over it.  The instructions say never to stop the hot engine without letting it cool down at idle speed first.  Otherwise, it backfires with a loud bang.  So what am I supposed to do, sit there while the thing idles down for a couple of minutes every time I am about to run over a beer bottle that some passing driver has tossed my way, or twig that has fallen off a tree?  I also have an elastic band to hold down the stupid safety lever that stops the push mower every  time I take my hands off the handle bars.  It's even worse of a PITA to manually restart that thing every time I release my grip, and re-start by using the pull cord no less.  Plus, those pull cords are not exactly easy to replace after they wear out.

[W2XR]

I have noticed that simply putting the vehicle in neutral at a light makes a difference. 

When driving a manual shift I always throw it in neutral at a light or other lengthy stop. It saves wear and tear on the throw-out bearing as well as on the hip and knee joints when you don't sit there and hold down the clutch for extended periods of time. Once you develop the habit, you do it without even thinking. I find it much easier, the "lazy" way. But I wouldn't think it would make an iota of difference in idling speed or fuel economy, since idling in neutral only involves overcoming the friction of the bearings in the the gear box itself vs the the friction in the throw-out bearing when holding the clutch down. Since you have to shift all  the way back down to the bottom before taking off anyway, it makes perfect sense to go half way (to neutral) while you are stopped at the light. But still, I don't see how that would cause the idle speed to drop.

Actually, Don, that is considered good driving practice. The throw-out bearing in an automotive clutch is not designed for high duty cycle operation. It is only designed for intermittent usage.

Prior to the introduction of the ball-bearing type of throw-out bearing, a carbon thrust bearing was used in many cars, including my 1957 VW. The duty cycle rating of the carbon thrust bearing is even less, and they would rapidly wear out in the event the driver resorted to depressing the clutch unecessarily for long periods of time.

Some folks think the clutch should be replaced as frequently as the brake linings in their vehicle, but the clutch in a properly driven standard transmission car should easily last 150,000 miles or more, if properly used and not abused, etc.

73,

Bruce

[KB2WIG]

My John Deere rider will self crap out only if the enjine and the whirling blades are engaged.


klc

[w3jn]

Some folks think the clutch should be replaced as frequently as the brake linings in their vehicle, but the clutch in a properly driven standard transmission car should easily last 150,000 miles or more, if properly used and not abused, etc.

73,

Bruce

Indeed.  I got 250,000 miles on the original clutch and throwout bearing in my old Chrysler LeBaron when my wife finally ran it over a speed bump and the subframe collapsed.  I got 225,000 on the original clutch in my 94 Chevy pickup.  The throwout bearing froze when my sister in law was driving it and she reefed on the clutch pedal so hard she broke the linkage.  I started it in gear and drove it home sans a releasable clutch.  Actually with that Chevy I rarely use the clutch, except to start out.

Key to long clutch life is easy on the throwout bearing as discussed above, no resting your foot on the clutch pedal, and clutch/gas timing such that the engine almost stalls on takeoff and accellerating/releasing the clutch simultaneously rather than revving up, then slipping the clutch.

In my experience a manual transmission is capable of much better gas mileage than an automagic.  Not only do you have no power wasted in the torque converter, you can anticipate traffic or road conditions and short shift or hold in a higher gear as necessary.

[K3ZS]

The quick start engines operate the same as the hybrids, not the solenoid driven, geared starter motor.

[k4kyv]

I got 225,000 on the original clutch in my 94 Chevy pickup.  The throwout bearing froze when my sister in law was driving it and she reefed on the clutch pedal so hard she broke the linkage. 

Man, I am glad I am not her husband.  Sounds like she could really kick some ass.

Key to long clutch life is easy on the throwout bearing as discussed above, no resting your foot on the clutch pedal, and clutch/gas timing such that the engine almost stalls on takeoff and accellerating/releasing the clutch simultaneously rather than revving up, then slipping the clutch.

I remember chewing my wife out multiple times until she finally got the message.  There was a stop light right at the top of a steep hill approaching where she worked. If she arrived at the top of the hill when the light was red, instead of putting the car in neutral and mashing on the brake pedal, she would rev the engine a little and let out the clutch just enough to hold the car immobile until the light changed. She was afraid of rolling backwards into the car behind her when taking off if she used the brakes. I replaced one clutch myself on a freezing winter day without any assistance with the transmission, before I discovered what she was doing.

[WQ9E]

Like Don I don't like the complete shutoff on my push mower that occurs if you release the safety bar so I keep a large spring clamp handy to clamp it if I need to move something.  I only use it for trimming but that is where you find the most stuff that needs to be moved, last week it was a couple of garter snakes

My Deere utility tractor just shuts off the PTO but leaves the engine running if you leave the seat.  You still don't want to do it accidentally since it has a brake built into the PTO that stops things in a hurry.  I don't think it is a big deal with the mid-mount deck but the rear deck I use for mowing the roadside has large and heavy swing mount blades and it wouldn't do the gear box any good to bring all of that to an immediate halt.   With the graphic illustrations of human wrapped around PTO shafts I won't defeat that safety feature.

I have gotten lazy over the years and just buy automatic transmission vehicles these days, the last standard I drove was a medium duty farm truck.  I have been very impressed with the Allison electronically controlled automatic in my pickup and I can't out think it and I certainly couldn't shift better than it does after years of driving automatic.  After using the cruise control linked automatic grade braking for the first time in the Rockies I am unlikely to buy a standard in the future (even if they do become available.).  I considered ordering my CTS with a 6 speed manual but laziness won out

[KE5YTV]

Guys, Your mower will let you get off while running if you disengage the blades and set the parking brake. Not a good idea to bypass the seat switch. If someone were to roll over on an incline it would be like wrassling a buzzsaw!! 

Mike

[W2PFY]

Not a good idea to bypass the seat switch. If someone were to roll over on an incline it would be like wrassling a buzzsaw!!  Shocked Shocked Shocked

Could possibly become a diss-ass-er 

[k4kyv]

Guys, Your mower will let you get off while running if you disengage the blades and set the parking brake. Not a good idea to bypass the seat switch. If someone were to roll over on an incline it would be like wrassling a buzzsaw!! 

Mike

I don't have any steep inclines that would likely cause mine to roll over.  That did happen to a friend, and he got a deep gash on the buttocks and severe injury to his arm and hand.  Despite repeated surgeries, he never recovered full use of the hand or got relief from the chronic pain till the day he died, over 20 years later. I don't think they even had seat switches on mowers when he had  his accident. The accident happened because of pure carelessness on his part.

A better  solution than the seat switch might be one of those gravity operated switches similar to what they use on portable electric heaters, that would disconnect the ignition if the frame of the tractor tilted beyond a certain limit from horizontal. Mine  has an electrically operated PTO clutch, so the seat switch could be rewired to cut off the PTO instead of the engine, as well.

Still, common sense and reasonable precautions are worth more than all those safety bells and whistles.

[WQ9E]

Mike,

The PTO engagement on my tractor is a separate control and I do shut it off before getting off the tractor; my earlier response was concerning some of the smaller lawn equipment that shuts the engine off.  There is an available override so that the rear PTO can be used without someone in the seat but that has to be set manually.

 I was dating a rather petite woman many years ago and she wanted to try mowing with the tractor, she was doing fine until she hit a bump lifting her off the seat and disengaging the PTO.  The tractor has ROPS and I do use the belt when mowing on slopes.  It weighs more than a small car and I don't want to be caught between part of the tractor and the ground!

Guys, Your mower will let you get off while running if you disengage the blades and set the parking brake. Not a good idea to bypass the seat switch. If someone were to roll over on an incline it would be like wrassling a buzzsaw!! 

Mike

[KE5YTV]

Don,

They started making riding mowers so they wouldn't backup with the blades engaged ! After a large uprising by customers, they put an override on the ign. switch to bypass that safety item. Sometimes you can vote with the wallet.  

Roger,

I was also talking about smaller riding mowers. I worked on riding mowers and tractors for Sears. I wasn't sure how the goverment has regulated safety on large tractors. I thought maybe they weren't as strict.

[Burt]

Ok, now I'm just looking for some opinions here, and not a gubmint argument thread.

It's been the constant topic lately in over the road contractor circles regarding the ridiculous expense of fuel. (Personally dropping 400 a week per truck here at $4.25 a gallon) Last week was a bad example, but we did a large job that required a few trucks on site and a couple pieces of fuel guzzling equipment. I have my sunoco receipts in front of me right this minute, and they total more than $3000 for the 10 day job.

At a time when we need every penny possible to push this thrashed economy forward, high fuel is hammering people and causing them to pull back their spending either in fear of even higher future gas/oil expenses, or just flatly, no money left over from their weekly nut to buy anything but fuel for their vehicles.

So the question is: Should the Federal regulators take the fuel away from the oil speculators? Would this help to normalize fuel costs, or would it do more harm than good?

Nice easy question, right? I figure with the diverse and highly intelligent group here, this is a good one for conversation.

Please again, no political ugliness or I'll be the first one to ask Steve to slam the door.

J

   

I do 60 MPH, everyone passes me, gas is still to cheap

[K5UJ]

I do 60 MPH, everyone passes me, gas is still to cheap

Or too many people are too dumb. 

[W2VW]

I used to get 3,000 miles out of the clutch in my 340 'Cuda.

I could launch a cassette from the in dash player all the way to the back seatback.