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Old 01-13-2010, 03:05 PM   #41
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Originally Posted by Scotty15 View Post
There are a couple settings in the "spark setting" box I'm not sure about.

"Cranking Timing" can be time based or trigger return. Mine is set to time based.

There is another box labeled "Hold Ignition". Mine is set to 0.

those are correct.
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Old 01-13-2010, 04:21 PM   #42
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For you guys that weren't raised working on cars with distributors, if the car is hard to start and acts like it is kicking backwards against the starter's rotation (which it is), then retard the cranking timing a few degrees and see if that helps. Keep retarding it a few degrees at a time until it cranks on the first try. It sounds like raising the cranking speed threshold is a good idea, too.

The term for this phenomenon is "kicking back" and not hydrolocking. Hydrolocking is what occurs when a liquid (hydro) (oil, water, fuel) is present in the combustion chamber and cannot be compressed thereby preventing the engine from being turned without damage.

Back a few years, kicking back commonly broke arms, shoulders, noses, and numerous other body parts when individuals had to hand crank automobiles. If the spark advance was not properly retarded when hand cranking, it could severely injure or kill you. Policemen were occasionally thrown over the handlebars of their kick-start motorcycles by the same issue.
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Old 01-13-2010, 04:23 PM   #43
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I'm convinced this is an ignition thing, at least for my car. And as I've said previously, I'm running Toyoda COPs, but it also did this with the stock ignition.
You dont have Spark A and B swapped do you?
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Old 01-13-2010, 06:55 PM   #44
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The car starts and runs just fine 90% of the time. So no, spark outputs are not reversed. When cold it does this pretty consistently. First turn of the key, tries to lock up. Second turn, starts up fine.

sixshooter-

I also own a 1926 Model T Ford. I am WELL aware of hand cranked engines and the dangers. Always put your thumb on the same side of the crank as your other fingers!
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Old 01-13-2010, 07:34 PM   #45
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As mentioned, I also thought there was no way a few cranks at 15ms PWs could flood the cylinders to the point where true hydro-locking occurs. I used that term loosely to describe the noise that occurs but Im glad it's not just me that suffers the problem of second attempt cold starts.

I'm playing every morning now before work to try and remedy the issue. Out of interest, can "kicking back" cause any adverse effect to the life of the engine or accessories such as the starter motor? After reading a few articles online, it seems it can.
I'll keep cringing until I can hope to tune it out.
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Old 01-14-2010, 10:04 AM   #46
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The only time I've ever encountered "kick back" was when I've had my spark inputs reversed or I was injecting way too much fuel. While you may not hydro-lock the car, you can certainly flood it enough where you cannot continue to start the motor as the raw fuel will not ignite.
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Old 01-14-2010, 10:29 AM   #47
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Is there a way to tell if there is either too much fuel or too little?
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Old 01-14-2010, 10:34 AM   #48
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The only time I've ever encountered "kick back" was when I've had my spark inputs reversed or I was injecting way too much fuel. While you may not hydro-lock the car, you can certainly flood it enough where you cannot continue to start the motor as the raw fuel will not ignite.
I check mine by datalogging and analysing my PW values during cranking.
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Old 01-14-2010, 11:02 AM   #49
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Is there a way to tell if there is either too much fuel or too little?

does it not start from lack of fuel or not start from too much fuel?
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Old 01-14-2010, 11:40 AM   #50
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does it not start from lack of fuel or not start from too much fuel?


no, but really, is there a way to tell?
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Old 01-14-2010, 01:57 PM   #51
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Yes - pull a spark plug and see if it's wet with fuel or not.
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Old 01-14-2010, 02:02 PM   #52
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and like I suggested before, you'll feel the "kick back" thing if it's getting flooded, you can also tend to smell it and sometimes even ignite large quantities of fuel and shoot off rockets in the exhaust.

if there's not enough fuel it will crank and crank and crank and crank without anything else odd happening, it just wont catch.
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Old 01-14-2010, 02:14 PM   #53
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My little mind agrees that the whole thing may be too long a fuel prime setting. This based on how some flooded engines behave - kicking back etc.
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Old 01-14-2010, 05:06 PM   #54
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Then explain why mine does not do this with the coil disconnected? I can crank, and then crank some more and it will turn over fine. And it doesn't flood while playing around with no spark. Plug the coils back in and it starts right up.

Plus why will it do this on the first turn of the key, then start right up on the second? You would think that would make a flooding situation worst.
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Old 01-14-2010, 05:10 PM   #55
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has tps? use flood clear mode and try with coils connected. how does it behave?
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Old 01-14-2010, 05:38 PM   #56
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Quote:
Originally Posted by Matt Cramer View Post
Yes - pull a spark plug and see if it's wet with fuel or not.
After how many seconds of cranking? How much fuel does it take to get a spark plug wet?

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Originally Posted by Braineack View Post
and like I suggested before, you'll feel the "kick back" thing if it's getting flooded, you can also tend to smell it and sometimes even ignite large quantities of fuel and shoot off rockets in the exhaust.

if there's not enough fuel it will crank and crank and crank and crank without anything else odd happening, it just wont catch.
If the injector pulse width is too small and you crank for a few seconds, won't the cylinder eventually get enough fuel to start?

I've had lower pulse widths and many seconds of cranking and a huge fireball/missile comes out the back. Is there a science to knowing the amount of fuel the engine needs to start up? CC's or PW based on injector size.
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Old 01-14-2010, 06:08 PM   #57
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has tps? use flood clear mode and try with coils connected. how does it behave?
I just went out and tried this. My TPS is connected, and it will enter "clear flood mode"

It turned over fine. I got a little pop out of the intake but of course did not start. It had also done that from time to time, so I'm not sure what to make of this. (The pop, not the no start, and yes I know why)

But I have to ask, if there is no fuel for the ignition to ignite, what difference does it make where the timing is? It could be silly advanced and with no fuel it can't kick back because there is nothing to ignite? We still don't know the answer to what is causing this. I'm voting for arbitrary too far advanced timing on that first turn of the key.

I'm tempted to go back to the LoRes code. I didn't have this problem then.
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Old 01-14-2010, 06:12 PM   #58
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I finally got a working tune burned in, Then I tried to start ( cold) and it did the hard cranking thing.
I played with the cold idle wizard and let the car cool off for a few hours .

Outside temps are near 70 but I let the motor cool off much as I could and moved the cranking timing from 18 to 15.

It started fine but I'll need a few more cold start ups to tell if the setting helped.

If it was up to me I would want less rather than more fuel at start up so as to not wash the oil out of the upper cylinder area at start up....but not sure how to do this

Last edited by poobs; 01-14-2010 at 06:23 PM.
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Old 01-15-2010, 06:32 AM   #59
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If it was up to me I would want less rather than more fuel at start up so as to not wash the oil out of the upper cylinder area at start up....but not sure how to do this
You're not sure how to have less fuel for cranking?!?

Maybe try reducing the Cranking PW for the desired temp
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Old 01-15-2010, 09:02 AM   #60
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Originally Posted by richyvrlimited View Post
You're not sure how to have less fuel for cranking?!?

Maybe try reducing the Cranking PW for the desired temp
Thanks. I will do that.

I started it up this morning. The temperature was in the 50s. It stalled once but there was no labored cranking.
Typically It runs a little rough for about 3 sec immediately after starting and then it recovers and idles fast until it warms up.
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