The clutch disc allows slippage as it is being engaged so unless you're just dumping the clutch, the crank isn't being yanked from zero to 500RPM in next to no time flat. Since dumping the clutch normally results in a stall or a jerk during normal driving, I don't do that, and neither does anyone else who is experience at driving a stickshift car. So for those people, they will let the clutch out gradually while bump starting a vehicle just as they do during normal driving. It's what they're used to doing.
Bump Starting Vehicles.
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The clutch disc allows slippage as it is being engaged so unless you're just dumping the clutch, the crank isn't being yanked from zero to 500RPM in next to no time flat. Since dumping the clutch normally results in a stall or a jerk during normal driving, I don't do that, and neither does anyone else who is experience at driving a stickshift car. So for those people, they will let the clutch out gradually while bump starting a vehicle just as they do during normal driving. It's what they're used to doing.
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Not in your case. I never said that anyone who thought about it did it in the manner that I described. Not at all. Now in my youth ..I surely have. I needed to get the car started and didn't have a whole lot of help to get it moving (alone) ..where the "ease the clutch" meant coming to a stop.
This is, and always was, a "what if" when someone suggested "damage". I merely described the differences in how you think of it ..and how it can be. Others have constructed inferences from that simple mission statement that aren't apparent in anything that I've posted. I've attempted ..in every way humanly possible ..to qualify that in spades.
I have surely got to check my meds. Maybe I should try art so I can see if I'm experiencing the Vincent Van Gogh effect in terms of perception.
This is, and always was, a "what if" when someone suggested "damage". I merely described the differences in how you think of it ..and how it can be. Others have constructed inferences from that simple mission statement that aren't apparent in anything that I've posted. I've attempted ..in every way humanly possible ..to qualify that in spades.
I have surely got to check my meds. Maybe I should try art so I can see if I'm experiencing the Vincent Van Gogh effect in terms of perception.
Consider also that the crank is decelerating from 750RPM (or whatever it happens to be turning at) to 0RPM in next to no time flat in the event of a stall.
Does this hurt the engine?
Does this hurt the engine?
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I've never said in any way that this damages the engine...ever ..reread the entire thread. If you can show me one statement that has said that damage occurs (except to maybe a mount or two that can happen anyway) ...I can see why some here insist on somehow discounting anything that I've said. Someone said that you can damage valves and I ..merely out of curiosity, explored the difference between a starter turning ..and the engine firing to "whatever" vs. the crank being turned way faster (and anyone here ..whether THEY do it or not ..can surely figure that SOMEONE COULD) from the drive end.
The comical part is that a few of you seem to discount what I said ..but also proclaim to have enough sense not to do exactly what I describe (naturally- cough -cough for other reasons)
The rest is constructed in your imaginations
The comical part is that a few of you seem to discount what I said ..but also proclaim to have enough sense not to do exactly what I describe (naturally- cough -cough for other reasons)
The rest is constructed in your imaginations
Couple of observations regarding how this thread has progressed.
First someone states that valves could bend with bump starting, then does not defend his claim when challenged, probably because he realizes he was wrong.
Second, Gary Allan takes things to a ridiculous extreme and then puts in a lot of effort trying to defend his position. In his efforts he disparages others' thought processes and also makes wild statements like pistons splaying around without proper compression and vacuum. Long before the engine reaches this amount of stress something in the driveline would have given way(like a driveshaft breaking) and the engine would not be subject to that kind of stress. I think Gary Allen is trying too hard here defending the indefensible.
First someone states that valves could bend with bump starting, then does not defend his claim when challenged, probably because he realizes he was wrong.
Second, Gary Allan takes things to a ridiculous extreme and then puts in a lot of effort trying to defend his position. In his efforts he disparages others' thought processes and also makes wild statements like pistons splaying around without proper compression and vacuum. Long before the engine reaches this amount of stress something in the driveline would have given way(like a driveshaft breaking) and the engine would not be subject to that kind of stress. I think Gary Allen is trying too hard here defending the indefensible.
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Well, (with a big smile on my face) I never said the effect was severe or mild or anything. I merely suggested that it was different. Everyone else in their "disparaged thought processes" made assumptions and couldn't employ adaptive thought ..even with the most extreme examples to "help" them see. The responses indicated that this was most assuredly needed.
Technical agnostics know this above all else.
For those who have had need to check their range and elevation in a head wind...
"See what you made me do??
You said, "who knows".
I just wonder if the effect on an engine from a stall would be the same as a bump start involving a clutch dump. In either case you're going from one state (running/not running) to the other very quickly.
When I compression-start a vehicle I try to get it to what minimum speed I think it'll fire over (usually just a few MPH), I then engage the clutch rapidly- just long enough to turn the engine sufficiently- then disengage the clutch rapidly. The engine will fire over the vast majority of the time when I do this.
I think I tried the slow-engage method and it seems the vehicle tended to jerk more than I cared for.
Never thought if my method is excessively tough on the drivetrain...
I think I tried the slow-engage method and it seems the vehicle tended to jerk more than I cared for.
Never thought if my method is excessively tough on the drivetrain...
before my sister went off to college i MADE her learn how to manually push start her 98 civic and i made her do it on a smooth gravel road which has higher rolling resistance compared to a tarmac road. she weighs about 130lbs and could push that car to a brisk walking speed, jump in and pop the clutch to start it. i figured if she could do it on smooth gravel then tarmac would be a piece of cake.
i also tought her how to push start in reverse (as if to coast backwards at walking speed out of a downsloped parking space and bump the clutch without actually pushing the car).
she has used this a few times to start the car and get home. a few times were because she left the lights on and the battery was so discharged that it wouldnt start the car but had enough power to run the ignition. once the battery went bad and didnt have enough power to start it. reciently her starter went out and she had to push start the car 2 times a day for a week untill she could get it fixed.
and you know what? bump starting isnt hard to learn. my sister doesnt know #@$%! about cars. but for someone with a manual transmission, to learn how to do this is invaluable. it can save you from being late to work, late getting home, save you towing costs, etc.
it isnt going to damage pistons, valves or cranks. thats a load of #@$%!. people do alot worse things to engines, like neutral drops and clutchless shifting at WOT and overheating and low oil levels and you guys are worried about a few drops of gas in the converter or some mystical made up stress on the crank and piston from push starting a car?
hahahah
as an interesting side story, i once had a honda elsinore 2 stroke 250cc motorcycle that was the easiest bike in the WORLD to start. all i had to do was put it in first and rock backwards briefly and then pull in the clutch. what would happen is the engine would do half a revolution in reverse and then fire the plug which would make the engine start spinning foreward and it would keep running in the normal foreward direction from then on out.
no kick starting involved, just a single gently bawkwards pull n the handlebars was all that was required.
my buddy had a benz with a bad starter or solenoid or some such thing. he had to awalys park with 1 wheel on a curb so that when he got in the car would roll off the curb and he could pop the clutch to start it.
this is one of the reasons i dislike automatics. no push starting an auto! makes me wish my automatic stratus was a manual, but i digress, the car was basically free so its hard to complain.
i also tought her how to push start in reverse (as if to coast backwards at walking speed out of a downsloped parking space and bump the clutch without actually pushing the car).
she has used this a few times to start the car and get home. a few times were because she left the lights on and the battery was so discharged that it wouldnt start the car but had enough power to run the ignition. once the battery went bad and didnt have enough power to start it. reciently her starter went out and she had to push start the car 2 times a day for a week untill she could get it fixed.
and you know what? bump starting isnt hard to learn. my sister doesnt know #@$%! about cars. but for someone with a manual transmission, to learn how to do this is invaluable. it can save you from being late to work, late getting home, save you towing costs, etc.
it isnt going to damage pistons, valves or cranks. thats a load of #@$%!. people do alot worse things to engines, like neutral drops and clutchless shifting at WOT and overheating and low oil levels and you guys are worried about a few drops of gas in the converter or some mystical made up stress on the crank and piston from push starting a car?
hahahah
as an interesting side story, i once had a honda elsinore 2 stroke 250cc motorcycle that was the easiest bike in the WORLD to start. all i had to do was put it in first and rock backwards briefly and then pull in the clutch. what would happen is the engine would do half a revolution in reverse and then fire the plug which would make the engine start spinning foreward and it would keep running in the normal foreward direction from then on out.
no kick starting involved, just a single gently bawkwards pull n the handlebars was all that was required.
my buddy had a benz with a bad starter or solenoid or some such thing. he had to awalys park with 1 wheel on a curb so that when he got in the car would roll off the curb and he could pop the clutch to start it.
this is one of the reasons i dislike automatics. no push starting an auto! makes me wish my automatic stratus was a manual, but i digress, the car was basically free so its hard to complain.
I would not have even begun to consider purchasing my '95 Civic if it were an automatic.
And what a fantastic car it has been- manual everything except the brakes, for some strange reason they are power-assisted. Even the ashtray is manual.
And what a fantastic car it has been- manual everything except the brakes, for some strange reason they are power-assisted. Even the ashtray is manual.
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