EOC seems pretty violent? - Page 2 - Fuel Economy, Hypermiling, EcoModding News and Forum

Twerp · 08-05-2008, 11:08 PM

Quote:

Originally Posted by Binger

what about for those of us with automatic transmissions...when I shut off at a light I put it in neutral to restart.

If I mounted a kill switch to the shifter I could put it in neutral and kill the fuel while rolling...but will it restart once I let off the switch because it is an automatic?

Will that cause harm to the transmission puting it back in D while rolling at 25-30mph? or less?

I'd be careful about doing EOC with an auto trans. I've heard that there are many auto transmissions that can be damaged by running without power to the fluid pumps. I'm no expert on this one, but I know that running an automatic Tundra with the engine off is not recommended. At the very least, look in your owner's manual at the section on towing/dinghy towing. If it gives you any warnings about running the driving wheels in neutral with the engine off, you might consider giving up on EOC and pursue other methods of saving fuel.

BrianAbington · 08-05-2008, 11:24 PM

I will look into that...I actualy tried some EOC going to and from work...and it did fine...but its good to know that there could be an issue...so I will find out.

I actualy did a 4 block eoc right into my drive way

MetroMPG · 08-05-2008, 11:41 PM

PaleMelanesian - thanks for posting that link. I'd forgotten about it.

cfg83 · 08-06-2008, 02:56 AM

modmonster -

I am pretty much in agreement with what everyone else has been posting. Here is how I describe a bump-start :

1 - Engine off, coasting at 25+ MPH.
2 - Push clutch all the way in.
3 - Move stick shift to 5th gear position.
4 - Let foot up on clutch just enough to engage engine and then push clutch back in. My non-car knowledge makes me think I am "tapping the flywheel" to turn over the engine. For me this is a pretty quick movement. If the tap goes well, the engine starts very smoothly, almost no bump in the bump-start.
5 - Let foot up on clutch and drive in 5th as normal.

I have experimented with lower gears, but the MPH "soft bump" range is very narrow, so I almost *never* do it.

CarloSW2

BrianAbington · 08-06-2008, 11:18 AM

I went to the mitsubishi dealership this morning and the mechanic I discused EOC with said there should be no issues doing this with my car.

I may give this a try for a bit.

When I was doing it last night I had no issues with my brakes or my steering. I'm not sure that it counts as a true P&G but omaha has alot of hills...and I can get my car rolling and shut it off in neutral and roll for a very long distance. I crested a hill at about 25 mph and had enough EOC momentum to cover a stretch of about 2 miles.

steensn · 08-06-2008, 05:13 PM

I have no problem doing a soft bump in second aroun 15 mph. I don't know if it is just my car, but I always use second gear at around 15 mph with the double clutch technique.

I use it so that I can judge lights and coast to them in time to never fully stop along with stop signs. I can coast all the way to 15 mph just before the stop sign using my brakes at the end and never use my ignition to start. Seems pretty seemless and I get great results.

texanidiot25 · 08-06-2008, 07:01 PM

Quote:

Originally Posted by Binger

I went to the mitsubishi dealership this morning and the mechanic I discused EOC with said there should be no issues doing this with my car.

I may give this a try for a bit.

When I was doing it last night I had no issues with my brakes or my steering. I'm not sure that it counts as a true P&G but omaha has alot of hills...and I can get my car rolling and shut it off in neutral and roll for a very long distance. I crested a hill at about 25 mph and had enough EOC momentum to cover a stretch of about 2 miles.

Interesting that they OK it. Most all Autos get their oil pumped from the spinning of the engine. With out the engine on, even in N the gears are rotating inside, but with no oil to lubricate. If you start having any weird transmission action, start the engine up and drive it easy and let the thing cool down some.

Autos are a PITA to have rebuilt.

skyl4rk · 08-06-2008, 11:04 PM

Quote:

Originally Posted by steensn

I have no problem doing a soft bump in second aroun 15 mph. I don't know if it is just my car, but I always use second gear at around 15 mph with the double clutch technique.

Try 4rth or 5th gear and see if it works, I think it would be easier on the engine. I used to bump start in the gear that I would normally be driving in at the speed in question, but have found that moving up a gear or two to bump start works better.

Frank Lee · 08-06-2008, 11:29 PM

I find the double-clutching method strange. I've EOC'd Fords and Metros both, and didn't need to double-clutch either. I just engage and disengage the clutch in the normal fashion. The whole operation is quite smooth. Is it just me???

steensn · 08-07-2008, 07:53 AM

Quote:

Originally Posted by Frank Lee

I find the double-clutching method strange. I've EOC'd Fords and Metros both, and didn't need to double-clutch either. I just engage and disengage the clutch in the normal fashion. The whole operation is quite smooth. Is it just me???

My car def does not like just engaging the clutch straight up. Even if I "get it right" it doesn't sound "happy." It sounds very smooth and much better doing a double clutch. I'm sure every car is different.