ReefRaider
Seaman Apprentice
- Joined
- Apr 14, 2009
- Messages
- 30
5.7 Mercruiser. Starts fine cold. No spark after it warms up. New coil, new cap, rotor. It will run as long as I leave it running (does not die on own), but as soon as I turn the key off, no restart, no spark from coil. So my question is, what other safety or otherwise switches are downstream from the coil that kill the spark? I heard maybe oil pressure switches? The one on the 'shifter'? Do my symptoms match anything in particular?
More......I put a test light on the coil. It lights bright on the positive, dimly on the negative side. As soon as I turn the key, light goes off. ?
While cranking, and not starting when warm, my oil pressure gauge only jumps up to about 20. That's still in the 'red'. If I'm either not getting the oil pressure, or the oil pressure sensors aren't working, will that prevent spark to coil?
What about the thunderbolt IV module thing inside the distributor. Except that it's upstream of the problem, right? Or could it still prevent spark when warm or failing. No idea what its job is.
Thanks in advance!
More......I put a test light on the coil. It lights bright on the positive, dimly on the negative side. As soon as I turn the key, light goes off. ?
While cranking, and not starting when warm, my oil pressure gauge only jumps up to about 20. That's still in the 'red'. If I'm either not getting the oil pressure, or the oil pressure sensors aren't working, will that prevent spark to coil?
What about the thunderbolt IV module thing inside the distributor. Except that it's upstream of the problem, right? Or could it still prevent spark when warm or failing. No idea what its job is.
Thanks in advance!
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