View Full Version : Info needed for the 40s K series

01-08-2012, 12:39 PM
I have a 45 K5 (possibly) theres no placards. what are the most common engine used in them? on the title it says its a 3500. what the cfm is on the carb and if i should even keep the oil air cleaner? im also having a sparking problem but i know i can take care of that when i convert it to a 12v system but does anyone know where i can find a 12v generator or brackets that could be used for an alternator......any info would help alot thanks

Allan E.
01-09-2012, 04:06 AM
I believe IH was using the Green Diamond series engines in the K5 trucks. If so, the engine will be green.
If you're having a sparking problem, replace the points, condensor, and coil. There's nothing else that can cause the problem if the coil is getting power.

Chances are you can have your generator rebuilt and reconfigured for 12 volts, or find one that uses the same housing that is 12 volts. If you need a bracket, nobody will be able to help you until they know which engine you have. I always leave the 6 volt starter in place for that, change out the light bulbs, and install a regulator to feed the instruments. If there is a fan and electric windshield wipers, they require a bit more work. I can't remember whether the K series had vacuum wipers or not.

You are in the heart of K truck country. Look up "sunflower reunion" and see when the next one is. There will be a plethera of knowledge about where to find parts for your truck. Lots of really good folks, too.

01-09-2012, 08:26 PM
Thanks. I already have the new bulbs and reducers for the starter and panel and I've started running new wire along with trying to clean up the few wires there are under the dash. There is a heater but i am going to leave it disconnected for now until I can go through it and make sure it was in working order. In all honesty i feel a bit foolish for asking some of these questions I'm an avid mechanic but theres not a whole lot of literature on this so better to ask questions then be sitting out in the rain.

Allan E.
01-10-2012, 09:05 AM
Binderbooks will have the manual. It will be worth its weight in gold.

I wouldn't try to reduce the voltage to the starter. It will simply spin faster with 12 volts applied. If anything, you'll want it re-wound so that it's made to operate on 12 volts. Auto electric shops do this all the time, especially in Kansas, where people use farm equipment from the WW2 era all the time. There's enough room under the hood to do whatever you want to do. That's the nice thing about old trucks.

With a 12 volt system, you'll need to add a ballast resistor to the ignition circuit. The 12 volt systems did that to keep from burning up the points, but most of them also started the engine with 12 volts to the coil, then reduced the voltage via the ballast resistor in the RUN position. The easiest way to do that is with a remote solenoid, such as is used on a 71 ford. This has the added advantage of giving you an isolator so that if the starter sticks, it won't continue to run.