Hey guys I just picked up a 49 F-6 and was wondering how do I tell if it has a positive or a negative ground...it has been sitting since 1991 but I got it to turn over and it wanted to fire but the starter kept free wheeling so I think I have the battery polarity reversed if it is a + ground...this is new to me any help would be appreciated

 

If your cranking it over now you have the battery hooked up right, but the starter could be giving you problems. My starter will start freewheelin when the truck tries to start, then I have to wait for the starter to stop to try again. Just be patient with it, and somebody else might chime in to help you out a little better.

 

Stock wiring will be positive ground, but it may have been changed by previous owner. Check the coil wiring, is the positive connection going to the distributor? Check your amp gauge when you turn on the headligths, does the gauge show a discharge? A discharge reading will mean that you have the polarity right. You may have to remove the starter and clean the threaded shaft for the sliding gear, but don't oil it.
...Terry

 

but wont the engine not start if the battery is backwards right? since the coils polarity is reversed ? well the starter quit on me yesterday so I think it needs a rebuild either that or the solenoid went but the lug on the starter was worn down anyway so it needs a new one either way I might as well get it rebuilt unless someone knows where I can get a lug for it also I dont think it was changed as the truck has fabric covered wiring all over it one more question is where does the wire from the coil go ? not the one that goes to the distributor the other one which terminal on the starter solenoid?

 

Which post on the coil goes to the distributor? If (-) then it is hooked up for negative ground. If the (+) or (batt) goes to the bottom of the distributor then you're set for positive ground.

The wire to the coil comes off the ignition switch in the dash (marked 'coil' on the back of the stock switch or 'ign' on aftermarket switches) Should be a red/green tracer wire.

I take it the 49 has a flathead in it.

The starter spins the right way even with the polarity reversed. It doesn't care.

If the starter is just spinning away without turning the engine over, you probably have a broken spring on the bendix. Remove the two long bolts that hold it to the bellhousing. Don't pull the bolts out, just back them off until they clear the threads. With 2 hands support the starter and lift it out of the hole. The whole shebang will come apart if you're not careful. Put a couple of nuts on the bolts after you push them back thru the endplate.

Several places sell bendix springs.