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hot start problem ls3

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Old May 10, 2010 | 03:05 PM
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Default hot start problem ls3

hi guys i have just fitted a ls3 stroker motor from scdp it turn over easy and starts and runs very well, sounds great and revs very well, idles well,and turns over with a ratchet on the crank nut. But run the motor for 10-15 minutes and stop it when hot and try to restart it wont turn over (just like a flat battery) which it is not i have tried 3 batterys,re wired it twice, ran extra wires, extra earths,etc etc all make no difference. it is pulling 350-400 amps when hot should be 175 ish ??, the wires dont get hot but the starter does. ive tried 3 std starters all the same, it all pionts to the starter not being up to it but i have ran a few motors like this with no problems, msd etc do a stronger starter , is it for this type of thing ?? comp is 11.4-1 so not that high, any help please people.
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Old May 10, 2010 | 04:33 PM
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sorry if this is the wrong section can a mod move it if it should be somewhere esle cheers,
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Old May 11, 2010 | 12:20 PM
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Try insulating the starter from the exhaust by using a heat shield or some wrap. I did that with mine and it made a big difference. I also run a power master starter, its clockable and more powerful then a stock type. One other thing you can do is run a #4 or #2 wire to the starter.
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Old May 11, 2010 | 02:30 PM
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Moved from Advanced Tech.
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Old May 12, 2010 | 10:03 AM
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i have tried heat sheild and massive wire , now just ordered a msd heavy duty starter as running out of ideas,
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Old May 26, 2010 | 11:26 AM
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still will now start hot !!!! pulling over 400 amps at start up even with the msd starter on it , it flys over cold and runs very well just wont turn over when hot any ideas please,
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Old May 26, 2010 | 01:10 PM
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Pull the plugs and check the rolling torque with it cold and hot. It could be a bearing clearance issue or something similar. Have you cut open the oil filter yet?
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Old May 26, 2010 | 01:23 PM
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Originally Posted by tinker-27
hi guys i have just fitted a ls3 stroker motor from scdp it turn over easy and starts and runs very well, sounds great and revs very well, idles well,and turns over with a ratchet on the crank nut. But run the motor for 10-15 minutes and stop it when hot and try to restart it wont turn over (just like a flat battery) which it is not i have tried 3 batterys,re wired it twice, ran extra wires, extra earths,etc etc all make no difference. it is pulling 350-400 amps when hot should be 175 ish ??, the wires dont get hot but the starter does. ive tried 3 std starters all the same, it all pionts to the starter not being up to it but i have ran a few motors like this with no problems, msd etc do a stronger starter , is it for this type of thing ?? comp is 11.4-1 so not that high, any help please people.
Did you mean SDPC?
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Old May 26, 2010 | 07:38 PM
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Check your cranking spark table to be sure it has enough timing pulled at temp.
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Old May 26, 2010 | 08:30 PM
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Originally Posted by Larry
Check your cranking spark table to be sure it has enough timing pulled at temp.
Great Idea. I was thinking about timing being too high too, but didn't think anyone had a reason to play with that table.

If you want to see if its timing related try upluging your coil packs and cranking it while it's hot. If it cranks over normal then you have a timing problem. If not then it's mechanical.
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