Resistance measurement differences

[wavrider]

Thought I would start a thread on differences betwen Seloc manuals and the CDI ignition troubleshooting chart for V4 ignitions 1972 -1978.

Seloc says timing base resistance should ohm 8.5 ohms + or - .2 between #1 and #3/ and #2 and #4 sensor wires. If out of tolerance replace.

Boatpartstore.com CDI troubleshoting matrix (which gets referenced alot in the forums) Says it should read between 10-20 ohms?

Stator resistance between the brown wire and the brown/yellow should read 500 ohms.

I believe seloc does not give a resistance check for stator.

What should the resistance be for stator reading? If boatsparts.com matrix is incorrect for the timing base resistance can it also be incorrect for the stator resistance?

Just curious to see what others forum members ohm readings may end up being compared to Seloc and the boatspartstore.com matrix.

 

[HighTrim]

Re: Resistance measurement differences

When in doubt, refer to the OEM factory manual as opposed to the Seloc. It is model specific. I find the CDI Troubleshooting Guide to be the easiest to follow, I believe it to be a bit different than the boatpartstore guide.

Also remember, some of the values present in the CDI matrix refer to CDI Electronics Blue Timer Bases, compared to OEM. Although, without checking, I believe it to be 30 to 40 ohms

 

[HighTrim]

Re: Resistance measurement differences

This is the download.

http://www.cdielectronics.com/Downlo...S/Default.aspx

 

[wavrider]

Re: Resistance measurement differences

HighTrim,

Thanks for the download, just doing all the research I can on this ignition.

So comparing anything I can find on resistance measurements, alot of members do not have a dva meter or adapter so resistance is the way to go.

I have one of the suspected bad powerpacks dismantled and in the process of reverse engineering it, mapping schematics just so I can understand how it functions in circuit.

Looks like basically transistor switching of the 150V from the stator input.
looking forward to finishing the project.

 

[HighTrim]

Re: Resistance measurement differences

Good luck!

You have the same 'mad scientist' disease that I have! My mom use to get so mad when I would dissassemble her washing machine or my dads lawn tractor to determine how it worked.

Since the neon tester are few and far between (I am still on the hunt for one, simply because they are dissapearing so quickly) DVA meters are a way of the future. For a do it your selfer, the DVA adaptors are pretty reasonable. Ebay usually has a vast array.

 

[wavrider]

Re: Resistance measurement differences

I know what you mean by the mad scientist disease.

Got an AM radio for Christmas, by new years had it tore apart and the output wired into an old curtis mathis console type tv and stereo I hauled home from the the side of the road with me and my friends bicycles. should have seen that bog old console and two 11 year old boys pushing that thing through town.
Swapped some tubes out in the console and got it to work, hooked the am radio into it and had it playing so loud that the neighbors complained, a block away.
every since then it has been electronics, made a living out of it, dad was a mechanic ASE and could not fathom why I did not like turn wrenches like he did.

DVA adapter, seen them on ebay, trying to find schematics to make one, should only be a few components, diode, capacitor and maybe a shunt to block rf.

 

[JustJason]

Re: Resistance measurement differences

instead of worrying about the resitance... what's the trigger outputting for voltage?

 

[wavrider]

Re: Resistance measurement differences

Requires a dva adapter to measure, got one on order hopefully have it in a few days, should be around 150v according to cdi chart if memory does not fail me.

 

[HighTrim]

Re: Resistance measurement differences

There has been a thread on this forum about making a DVA adaptor, cannot remember for the life of me who authored it, if I think of it Ill let you know.