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no spark at all on one engine , related to timing shunt (454 crusader)

erich said:
Why not swap modules between the two engines? That should prove if it is the module or not, unless they are specific to engine rotation.
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erich.....not a bad suggestion, but at this point I am afraid to risk blowing another one. FYI i did swap them last week when I first encountered the no spark issue on the starboard side, and the one in question fired up the other motor just fine. I did not check timing on that module however while it was swapped. Reminder to all of my helpers here, this is on the counter rotating starboard side. The balancer turning counter clockwise when viewed from front of engine, resulting in advanced timing mark coming up on the right hand side of timing tab, as opposed to coming up on left hand side of tab on the port (standard rotation) motor when viewed from the front.
Throwing this out there for further consideration....prior to the stalled engine, no spark event....I had over ridden the base timing with shunt because it was not advancing enough by running it up to 2500 rpm and advancing the distributor to obtain 28* advance at that speed. This action resulted in an idle speed timing of more than 12* advance WITHOUT the shunt. In speaking with the technician at the place where I bought the Delcos a couple months ago, he told me that 12* advance at idle was excessive, and he stated that condition could in itself cause a no spark issue. He advised me to retard the distributor a bit to see if that cured my problem, which it did not. As I reported, it turned out to be a loose run wire under the helm. So now the engines are running again, but I am not seeing the advance on that starboard motor that I think I should be seeing.
 
realcaptron said:
erich.....not a bad suggestion, but at this point I am afraid to risk blowing another one. FYI i did swap them last week when I first encountered the no spark issue on the starboard side, and the one in question fired up the other motor just fine. I did not check timing on that module however while it was swapped. Reminder to all of my helpers here, this is on the counter rotating starboard side. The balancer turning counter clockwise when viewed from front of engine, resulting in advanced timing mark coming up on the right hand side of timing tab, as opposed to coming up on left hand side of tab on the port (standard rotation) motor when viewed from the front.
Throwing this out there for further consideration....prior to the stalled engine, no spark event....I had over ridden the base timing with shunt because it was not advancing enough by running it up to 2500 rpm and advancing the distributor to obtain 28* advance at that speed. This action resulted in an idle speed timing of more than 12* advance WITHOUT the shunt. In speaking with the technician at the place where I bought the Delcos a couple months ago, he told me that 12* advance at idle was excessive, and he stated that condition could in itself cause a no spark issue. He advised me to retard the distributor a bit to see if that cured my problem, which it did not. As I reported, it turned out to be a loose run wire under the helm. So now the engines are running again, but I am not seeing the advance on that starboard motor that I think I should be seeing.
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a couple of notes. First: both engines have (or should have) identical distributors. They spin in the same direction and have the same hardware top to bottom. Second: at 2500 rpm the timing is likely still in transition. I'd go to 3500rpm or even 4000 to see what happens there. Of course, doing this at idle is perfectly fine and safer than at speed. There is no reason to do any of this work in gear.
 
diver_dave said:
a couple of notes. First: both engines have (or should have) identical distributors. They spin in the same direction and have the same hardware top to bottom. Second: at 2500 rpm the timing is likely still in transition. I'd go to 3500rpm or even 4000 to see what happens there. Of course, doing this at idle is perfectly fine and safer than at speed. There is no reason to do any of this work in gear.
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Yes, they are identical distributors that each rotate clockwise.
 
I don't think you need to go past 3000 to get max advance on an EST.....and the tech either has a bad memory or hasn't done a complete check on a running v-8 engine....its not uncommon to get up to 10 deg increase in timing (@650 RPM) when the shut is disconnected, when running on the module.
 
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