I've been out of the loop for nearly a year now - work and life got too crazy for me to carve out any time to play with my truck since last fall. To make a long story short, the starting issues that plagued me then have not ended, despite tons of rewiring.

So far, I've replaced the alternator, voltage regulator, resistance coil, dash harness, headlight harness, ground straps, starter cable, battery cable, starter solenoid, headlight switch, ignition switch contacts, starter button, and refurbished the cluster. The system is 6V positive ground, with a single wire alternator.

Here are the symptoms: I charge the battery, connect the battery's quick-disconnect to make the current continuous, hop in the cab to start it up, press the starter button, and nothing happens (not even a click from the solenoid). If I disconnect the starter button wire and touch it to the frame, the starter cranks, but slowly and not enough to start the engine (same thing happens if I press the button on the solenoid). So, it seems clear to me that the starter button isn't working, but there's also more going on. If I try to start it a few times in succession, the starter motor struggles again, and each time I do this, it seems weaker and weaker, as though the battery is quickly draining. Things smell hot (electric hot, if you know what I mean) at this point, and if I touch the starter cable at this point, it is quite warm, and the negative terminal of the battery is HOT. So, I'm thinking that the starter motor is bad, and that it's working against a large resistance and is drawing a massive load. Is there any other explanation I should be considering at this point, like a bad ground or a short somewhere else in the system? If so, is there an easy way to narrow it down? Any help would be greatly appreciated, and you can't make the explanation too simple for me (I have limited knowledge/comfort with electrical systems).

It's been sad having the truck sitting unused for over a year!

Thanks,
Cap'n Sygo

 

Welcome back! Since starting is all battery and if you have no dead cells in it, I'd look towards the starter. Begin with the cables, they have to be huge for the amp load, then look to the grounds to the frame from the engine (important one) and then test the solenoid. It should be clean where it touches the cable and the firewall. I'm guessing when I think that you meant "generator" not alternator? Ok, so check the cable to the starter next. Then pull the starter if there is nothing left to check. Be careful with it because the mounting bolts also hold the starter motor itself together. Make sure you find some nuts or something small enough to hold the bolts in the starter after you remove it. You can either test the starter with some jumper cables or see if the local NAPA can test it. 6 or 12v, it doesn't matter much. Remember that twice the voltage equals half the amperage, so I'd test with 6v if you can to see if the starter windings can handle the amp load. Make sure all of the hot cables are good.

 

Are your battery cables adequate for a 6v system? I think 00 gage is recommended. Also, do you have enough grounds? I ran cables Bat(+) to cab, cab to frame, and cab to motor. And make sure all connections are clean. Maybe check and see that the starter motor to engine mount is nice and clean. If all that checks out good then maybe your starter needs rebuilt. Hope you get it sorted out!

 

Hi Lee,
Thanks for the speedy reply! The battery is about a year old - how would I check for dead cells, other than to take it to the shop I bought it from?

As far as the cables go, this is the battery cable I installed. And this is the starter cable. I'm assuming that since these are listed as being compatible with '47 Ford trucks, they should be the real deal. I guess you're suggesting I might have fried, them, though. Would it be ok to test the 'bad cables' hypothesis by substituting jumper cables for them?

When you say that the solenoid/firewall connection should be 'clean', do you mean shiny bare metal? The solenoid is bolted to the firewall, which does have a coating of paint, but I was figuring (hoping?) that the inner edge of the hole cut for the bolt would make a good contact. Ditto with the ground strap from the engine to the firewall. Should I just scour the face down to bare metal for each of those spots on the firewall?

Thanks again!
Cap'n Sygo

 

Is your dash painted nicely behind your starter button? The button grounds to the dash. If there is corrosion, or nice new paint, and the button cannot get a good ground then you get no action when you push the button.

As mentioned above 6V likes nice large internally clean battery cables. Nothing that can be purchased already made up at your average auto parts store is large enough. One other area that probably isn't your problem but you should be aware of: If you have good cables try tightening up the nut holding the stud on your starter. If that gets loose then you can have extra resistance there.

Update: you posted while I was posting. Since it looks like your cables are decent onto the next areas. The ground strap location on the fire wall needs to have no paint where the strap connects. You don't need a large area, but clean metal is necessary. This also is true for the solenoid and the starter to oil pan surface (remember the starter needs to ground too).

 

Hi Joe,
Thanks for weighing in, as well. I don't see the gauge or voltage listed on the Mac's site for the cables I've linked in the message I just posted, but I figured that if they were marketed as being for this vehicle, they should be ok.

Just checked the grounds, and I've got two that I can see: battery to engine and engine to firewall. Where should I look for the firewall to frame ground? I don't recall seeing a strap sold for that. The reason I grounded the battery to the engine was that was how the the grounds were set up when I bought it. Is it more typical to ground the positive pole of the battery to the firewall? If so, where on the firewall? This seems like a place where the puzzle could get solved!

When I first got the truck, there were troubles with starting, and at that time, I took the starter off - I remember checking to make sure that where the face of the starter meets the engine was nice and clean, and it was.
Thanks again!
Cap'n Sygo

 

Hi Fred,
There is fresh paint where the starter button is inserted. I'll scrape it down and try again (hopefully I haven't fried the new starter button already). The cable is tightly connected to the starter, so I don't think that's the trouble. However, I suppose the starter might not have a nice clean surface at that point. I'll also shine up the firewall behind the solenoid and where the strap connects. I'm curious about the discrepancy between my strap configuration and Joe's, and if that might be a factor, as well.
Thanks,
Cap'n Sygo

 

I should have been clearer, my apologies. May flathead era Fords were either factory equipped with a small braided engine to firewall ground strap or had one added over the years. I was referring to this.

I doubt you have hurt your starter button at all. It simply makes contact between the dash and the starter button wire. It is a wonderfully simple setup, the type that engineers today seem to find ways not to design.

Since you asked the question I don't actually know where the correct ground cable placement is on your truck. I have seen grounds to engine on a lot of the old Fords, my 53 is set up this way. However, on page 263 of the 49-50-51 truck shop manual Fig. 37 states ground return through frame. Someone on this forum is bound to know how Ford originally did it on your truck. However, if your strap is attached to the engine with clean metal then your starter solenoid or starter motor are not working properly.

 

The ground cable configuration you have now should provide for good cranking. I think the ground to the frame is for lights. You mentioned your cables getting warm when cranking the motor. If the cable connections are nice and clean then that means the cables aren't thick enough to handle the amps. You can get 00 cables made to order at NAPA or a welding supply shop.

 

I've got this new braided strap from the engine to the firewall. Another similar (but longer) strap connects the +pole of the battery to the engine block (I'll polish that spot to make it shine, and see if that helps).
Thanks again!

 

Thanks, Joe. I'll check all of the connections, and will report back in the next day or two.

 

Cap'n , I will be up at Lynden on Aug 3-6th. That's wed thru Saturday. Berthusan park Puget Sound antique tractor and Machinery Asso annual show. I set up every year (30th year for me)... We just hang out waiting to help someone get their stuff working. The show is 'closed' in the evening but that's when we do most of the wrenching. About half of my buddies are Boeing guys and they know all the technical stuff. That;s the only reason I can even get my worn out stuff back to Orcas at the end of the show. Please look us up. Park on a hill, roll start it and Cliff, Eric and Fred will figure it out on the spot. I will bring a known good starter as well.......

 

Hi GB - I saw in an earlier string that you were going to be up at the tractor show. Sadly, I'm going to be away that week, spending time with friends on the OR coast. I couldn't have done what you suggested anyway (drive the truck up there) since I can't start it, and I still haven't fixed the no brakes issue. One step at a time, right? Next time you're up our way, I'd love to bribe you to swing by our place and check the rig with me...maybe a case of beer would do the trick?
-Cap'n Sygo

 

Lee - I realized that I never said anything about your generator/alternator question. What I've got is a 1 wire alternator, not a generator. More info on them at this site: 6 volt alternators - Positive Ground
-Cap'n Sygo

 

The frame strap I have is attached to the transmission mount (top side). It was there, so I hooked it back up. Apparently the positive grounding likes a "return" line. Your alternator is like mine, except positive ground.