I hope someone has a bit of advice for me on my problem. I have just finished installing a used 6Cyl flathead 7HA into my 48 F2. I purchased this about 2 months ago after being told it was pulled out of a daily driver that was being hot rodded this spring. the engine turns freely with a 1/2" ratchet but when I try to turn it over with the starter it turns abut 1/2 a revolution and then stops. i have been jumping it with a 12 volt running truck and on occasion it will turn over 6 or 7 time until it stops. this is what i have done alread to try and fix the problem: Swapped out the starter and the solenoid. cleaned all the the battery connections had the clutch pedal down while turning it over. Nothing seemed to make it any better. all of my other work on 6 volt systems once I jumped it with a 12 volt it turned over like crazy. Any ideas would be great!

 

Yer 48 should be positive ground 6 volt. Ya can't jump it from a running negative ground truck or it will try and turn backwards. If ya got yer battery hooked up backwards than that is why it wont turn over even with a new starter. Is the plus side of the coil going to the dizzy or ignition switch? If plus on the coil is going to the Dizzy than it it still positive ground.

 

All FoMoCo vehicles thru 1955 are 6V positive ground. 1956 was the first year for 12V negative ground.

6V battery's require large diameter cables. Do not use the thin cables that 12V battery's use.

You bought a used engine, so you prolly didn't hear it run, so it may be locked up.

It came from a DD? Uh huh...Do NOT believe a single word a seller claims, as sellers can lie just like used car dealers and lawyers.

 

The truck is hooked up as a positive ground. the engine doesnt even turn over fast enough or enough time to start. it does turn over by hand by a ratchet or even by hand if I grab the fan blade. I dont think the engine is locked up.

 

Like Bill said how big are yer cables? 6V needs a whole lot bigger cable than 12 volt. Sounds like ya aint getting enough juice to the starter motor to me at this point. And yer positive grounds need to be clean clean clean. All of them.

 

Somebody will probably scream at me (hehe), but here's an idea. Get yourself a 12 volt battery and unhook the starter cable from the solenoid and all the ignition wires, and leave the ignition OFF. Hook it up with the positive to the ground cable and tap the starter cable on the negative terminal of the battery. If she's gonna turn, she'll turn that way. But obviously be ready to pull the cable away if the engine is not turning freely. You'll find out if it truly is a lack of battery power that way.

 

Ya know Doc. That is exactly what I would do and have done oh so many times. Like you I was scared ta say it. Bud be careful okay. But no more dangerous than jumping 6V positive ground with 12V negative and that with the engine running.

 

Is it possible your timing is so far advanced or out of time that it would cause the starter to kick back?
If it will turn smoothly with a ratchet it will turn with the starter if everything is correct.
The starter and flywheel could be mismatched or out of alignment.
There has to be a connection between power being applied to the starter and the engine not turning so look carefully at the starter and flywheel alignment and timing, Since your trying to start and ignition is firing timing could be the link. You can eliminate that by unhooking the wire to the coil or just jumping the battery to starter as was suggested taking all other wiring out of the picture.
Good luck and hope you find your trouble.
Larry

 

Yeah I've said "hey y'all, watch this" a few times in my life. It worked when my stuck flathead started rotating (after 6 days of soaking) but still wouldn't totally turn freely with the 6 volt battery. Just understand what I said, unhook everything else to the point that you're dealing with nothing more than a 12 volt battery and that starter motor. By the way there "nicpapageorgio", maybe you and I can go to vegas sometime and you can win me another truck with a slot machine. Heck of a name choice. Hilarious.

 

The starter will spin the correct way with either polarity. Take the plugs out and see if it cranks freely and builds oil pressure. See if coolant sprays out of any of the cylinders. Which starter did you use, the old one or the one from the new engine? A bad starter is hardly news in these old engines.

 

We Should Mountaindoc. Put a dollar in and won a 48 for dF2 with a blown motor though.... The cables are definately oversized with all soldered conectors. I cleaned all of the connections thouroughly. I used my jumper cables from my running 12 vot truck and put them right to the starter and the same results would only rotate 1 time most of the time and 6 or 7 time nce in a while. I replaced the starter that came with the motor with the one that came with the truck that used to work fine and they both had the same symtoms. there isnt any grinding when i hit powere to the starter but could it be an alignment problem witht he flywheel or the wrong flywheel. I will try starting it without the plugs in tomorrow and probably throw a 12 volt batery in it too.

 

AHH!! Finely the Rest of the story. Yes Try spinning it on 12V with the plugs out. Let us know what it does.

 

Yeah keep us posted. I hope those people who sold you that motor are telling the truth. I kid you not when I say that a probable rat's nest shot out of my truck's tailpipe and across my garage floor the first time I got it started. Not too long ago, a guy posted some pics of a flathead that he tore down after removing it from his truck. It had the most awful looking rat's nest in the oil pan that I've ever seen.

 

I seen that also Doc. What a mess. Wonder what he did there. I would have cleaned it up and tried to run it. But that's just me.

 

Here is a mouse nest I picked up a year ago or so, paid $25 for it,



it was sitting in the grass out behind a farmers shed. bad thing was the mouse was still in it when I took it apart, had to be quick before it got loose in the garage!

I just picked up a flathead 6 with trans this week, it came out of a 51 F-1. I really don't know anything about the straight 6's it turns over and seems ok??? anyone know would a 239 V8 flathead starter work on it? I probably shouldn't have picked it up but when it was only $50 I figured better me than the scrap man. The people where cleaning up the farm because it had been sold to a developer.
going to try and clean it up and see if it will run.