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Old 09-18-2013, 11:41 PM   #11 (permalink)
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Quote:
Originally Posted by RobertISaar View Post
since it's relevant... thought i've had about bump-starting lately is putting the throttle on the floor(or at least, opened significantly) before letting the clutch out to prevent the instant engine braking that would happen with a closed throttle plate when going from 0RPM to whatever the engine would spin up to when in gear.

seems like it would be less strenuous on both the clutch and engine.
Maybe. Once the engine stops spinning though, the inlet manifold very quickly fills with air at atmospheric pressure. Every time you start the engine, it is, initially at least, in an equivalent state to wide open throttle.

It's (throttle open) easy enough to try anyway.

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Old 09-19-2013, 04:15 PM   #12 (permalink)
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Fuel cutoff solenoid prevents pulling unnecessary fuel through the lines during key-off engine revs. I don't know how old your carbureted car would have to be to lack a cutoff solenoid; I think Toyotas had it in the 70s.

But it makes a huge difference to let it run down to idle and run there for a second or two before keying off. Turning off while still at high revs pulls too much fuel through unburned, and it almost guarantees a nasty backfire at the next key-on. And if you look back through my history, you can see where a backfire blew my (admittedly cheap) muffler wide open. So I spare a few milliliters of fuel to prevent that. It's worth it.
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Old 09-19-2013, 08:02 PM   #13 (permalink)
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Causing the backfire was sport in my (misspent) youth. Some of the responses of bystanders were amusing until I considered that, given returned vets and gun massacres, they could have been genuinely in fear for their lives.
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Old 09-19-2013, 08:37 PM   #14 (permalink)
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Quote:
Originally Posted by Occasionally6 View Post
Causing the backfire was sport in my (misspent) youth. Some of the responses of bystanders were amusing until I considered that, given returned vets and gun massacres, they could have been genuinely in fear for their lives.
In Phoenix, when the walk sign comes on at intersection, there is some clicking sound which, to me, sounds like a machine gun.

I first heard it at the VA.
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Old 09-20-2013, 06:30 PM   #15 (permalink)
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Some folks believe that bump-starting an engine with carburettor is safer than doing the same in one with EFI.
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Old 09-20-2013, 09:36 PM   #16 (permalink)
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With my cts-v I have do a quick up down with the clutch pedal to get the smoothest kick start. A bump start should do no wear. Your using the clutch to rotate the engine internals, normally your using the clutch to move an entire vehicle.
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Old 09-21-2013, 07:07 AM   #17 (permalink)
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With my cts-v I have do a quick up down with the clutch pedal to get the smoothest kick start.
By "kick start" you mean starting with the vehicle still in motion after an EOC?
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Old 09-21-2013, 02:55 PM   #18 (permalink)
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By "kick start" you mean starting with the vehicle still in motion after an EOC?

Si senior. I should have said bump start, the motion I use with my leg would probably look like I was kick starting something.
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Old 09-24-2013, 07:36 AM   #19 (permalink)
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Kick-start in this case actually makes sense

BTW once I've considered to work around a boat-like supplementary pull-string starting setup for an old Pontiac Trans Sport which was having constant starter failures.
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Old 09-24-2013, 01:57 PM   #20 (permalink)
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Quote:
Originally Posted by Occasionally6 View Post
Causing the backfire was sport in my (misspent) youth. Some of the responses of bystanders were amusing until I considered that, given returned vets and gun massacres, they could have been genuinely in fear for their lives.
When I was in college, someone was driving an old truck through the campus and let off the gas to slow down to let people cross. When the driver got back on the gas it backfired 4 or 5 times.

Probably 10 kids dropped to the ground.

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