OL Reading on a 28 truck

rivcokid

rivcokid

Senior Member
Hi all - I'm trying to get a friend's 1928 truck going and having no luck. It would crank and not start. Then, we heard a pop and it won't even crank now. When I put the voltmeter on the battery and the starter, it reads "OL" which I've determined means open loop. The truck is pretty stock but has been converted to 12 volt negative ground.

Any ideas of where to start on this?

Thanks
 
"OL" on a modern meter typically indicates "Over Load" or "Out of Range". Be sure that if this is a multi-meter, that the DC Voltage mode is selected. Next, if it is not auto-ranging, set the appropriate scale for the 12V system; that may be 20V. Or better yet, set it to the highest range first, then move down if a lower range will work.
 
Follow advice of Sinbad. Once you get a true voltage reading on the battery, move to the terminal on the starter switch and measure the voltage there. Then move to the posts on the junction box and measure the voltage there. Then move to the coil. Then to the points with them open or a card inserted. You may have something as simple as a loose or corroded battery connection or ground strap.

A "pop" can come from a number of things. Please describe what the pop sounded like. Was it electrical or mechanical. The starter Bendix drive could be stuck. Does the engine turn over with the hand crank or in when you push the truck in high gear?

Everyone on the Barn are willing to try and help you but more detailed information is needed. You can also search out someone local in Riverside via a Model A club.

A useful site for all things electrical is at: https://www.mafca.com/downloads/Seminars/2018%20Reno%20Electrical%20System%20Alex%20Janke.pdf
 
A 12-volt conversion has to be done properly. The coil should be either a 3-Ohm primary type for 12-volt or it could be a 1.5-Ohm primary type with a ballast resistor. No telling what ignition switch it has. It may have a model A distributor mounted condenser or it could be some conversion. Coils are polarity sensitive so power should be on the + side with negative ground.

The engine may have stuck valves. No telling what the fuel system condition is. It has to be clear, clean, & well adjusted.

If the truck ran recently, resuscitation should be less problematic. If it's been laying up for several years, there could be any number of problems.
 
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Thanks all - it's only been since about February that it hasn't started, and I was assured that it ran fine then, so I'm thinking it's still something small. I'm going back over there in a few days. Will take your advice and see what happens. thanks again!
 
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