V6 135hp 1988 DVA test Coils...Cranking or Idle ??

[aussieflash]

Gday All,
Built a DVA a while ago and excited to test it out.Going to set my multimeter to 500vdc and want to test the coils output.
My question is can i do this while engine is at idle or cranking only.I will be using a remote starter button to solenoid if it needs to be cranking only.
Can I just ground neg lead and move pos test lead from coil to coil while motor idling?
Even though i built my own DVA and remote test button,I am still considered an electrical idiot!
Thanks for any help.
Paul.

 

[CharlieB]

Re: V6 135hp 1988 DVA test Coils...Cranking or Idle ??

Coil output or switchbox output to the coil?

Coil output is far more than 500V, usually coil output is gauged by spark color and gap, hot blue across a 7/16 gap.

DVA testing of stator, trigger, and switchbox outputs are great troubleshooting to determine why the coil does not produce a quality spark.

 

[aussieflash]

Re: V6 135hp 1988 DVA test Coils...Cranking or Idle ??

Lets say switchbox output to the coil then.Can I test this at Idle?Do I ground blk test lead then put pos lead to each coil connection at switch box?
Mainly want to see if DVA works,then i can trouble shoot with confidence.
A while ago while idling on muffs I pulled each plug out 1 at a time then put back.When #3,4,6 plug came out idle didn't miss a beat and #1,2,5 idle dropped noticeably.Yet when I took it for a run it had no problems getting to 5600 RPM.

 

[CharlieB]

Re: V6 135hp 1988 DVA test Coils...Cranking or Idle ??

Generally DVA tests are done cranking as voltages increase with RPM, however, if a system seems to develope a problem at RPM then testing both cranking and again at RPM may be helpful to isolate the problem.

A great resource is the CDI Electronics Ignition Troubleshooting Guide, it has specific directions with charts for most every outboard there is. And it is FREE, if this link doesn't work use the search feature as it has been posted numerous times within iBoats. Download it, save it, it is almost THE ignition Bible.

CDI Electronics Practical Outboard Ignition Troubleshooting

 

[aussieflash]

Re: V6 135hp 1988 DVA test Coils...Cranking or Idle ??

Thanks CharlieB,ive got the CDI info but it didn't say anything about Idle,cranking etc.

 

[ENSIGN]

Re: V6 135hp 1988 DVA test Coils...Cranking or Idle ??

All diagnostic tests on mercury ignition systems are done at cranking speed.Remove the spark plugs so it can spin freely.