The Ford Barn

rivcokid · 07-22-2023, 01:56 PM

**UPDATE** - It seems as though the starter is the issue. I took it to cars and coffee this morning and it ran fine going there. Went to leave, and dead. I put it in gear and moved it only a bit (didn't even get out of the car, just rocked it) and it started right up! I'm not going to give up on the grounding possibility - this car sat for at least 5 years prior to my purchase, so it can't hurt. But it looks like I'll need to pull the starter and play with it.

Thanks again to everyone for advice! I'll keep you up to date on progress!

Flathead Fever · 07-22-2023, 02:14 PM

First thing to is while trying to crank the engine smack the strarter with a hammer. Hopefully it's not a nice, restored starter. Mi used to working on fleet vehicles where you could beat on them. Sometimes but not always it will start cranking if the brushed are starting to fail. You can do this when they are first failing but eventually the smack test won't work. That was the first thing we did when we know we had battery voltage and an engine would not crank. If it cranks when you smack the starter you can be pretty sure the starter is at fault.

If that don't work than this is what you need to do nest, a "voltage drop test" across every switch, cable and connection while you are trying to crank the engine. It will definitely find the bad spot. This is how professional mechanics find those opens and excessive resistance in circuits. It's an easy test to do. I would start with testing across the starter switch, the contacts are could be burned.

Resistance is a blockage just like a blocked water pipe. If you were to drill holes in both sides of the blockage in a water pipe you could route the water flow around the blockage. That is exactly what the voltmeter is doing in a voltage drop test. The voltage can't get by the blockage, so it tries to flow through the easier path of resistance through the meter and you see it as voltage reading. There should not be more than .1V to.2V volt drop or there is resistance. Current has to be flowing to do this test.

Watch this video and there are many others on voltage drop testing. You must have a voltmeter to work on electrical stuff or you are just guessing. Your starting circuit is much simpler, but the testing is the same. Doesn't matter if its 6V, 12V negative or positive ground this how you diagnose it.

https://www.youtube.com/watch?v=WMXE...ENKujYtc&t=633

rivcokid · 07-22-2023, 03:20 PM

@Flathead - thanks! I'll print your post out and give that a try too!

rivcokid · 09-14-2023, 02:04 PM

**UPDATE #2** - Well, it finally cooled off enough for me to play with the roadster. I got new battery cables including the copper positive version like the original. I removed both of the old ones, took a wire brush (drill-end kind) to the connection on the frame and transmission, reassembled the system, and it starts like a charm! In fact, it seems stronger too. Now, that said, I started it about 8 times this morning with no problems - but this was intermitant, so the next test is to start it several times over the next few days and see what I come up with. I'm cautiously optimistic, though. Thanks again for all the tips!!

Rob Doe · 09-15-2023, 03:50 AM

rivcokid, x2 on post 22 except for his following description:

"That is exactly what the voltmeter is doing in a voltage drop test. The voltage can't get by the blockage, so it tries to flow through the easier path of resistance through the meter and you see it as voltage reading."

You can find a description of how to "voltage test" the Model A starting system in Chapter 2 of the blue, Les Andrews "Trouble Shooting and Diagnostics" guide. There are other simple volt meter tests for faulty connections etc.

Warning: an ohmmeter cannot be used to find a faulty battery cable or wire.

Rob Doe · 12-18-2023, 04:50 PM

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Rob Doe · 12-18-2023, 05:02 PM

Riv, any update on this problem???

Synchro909 · 12-18-2023, 06:13 PM

Quote:

Originally Posted by Rob Doe

Riv, any update on this problem???

Ditto. I must have missed this thread when it started. I had the same thing happen years ago and might have the solution if the OP hasn't found the problem.

07-22-2023, 01:56 PM	#21
rivcokid Senior Member Join Date: Sep 2018 Location: Riverside, CA Posts: 174	Re: Frustrating start problem UPDATE - It seems as though the starter is the issue. I took it to cars and coffee this morning and it ran fine going there. Went to leave, and dead. I put it in gear and moved it only a bit (didn't even get out of the car, just rocked it) and it started right up! I'm not going to give up on the grounding possibility - this car sat for at least 5 years prior to my purchase, so it can't hurt. But it looks like I'll need to pull the starter and play with it. Thanks again to everyone for advice! I'll keep you up to date on progress!

07-22-2023, 02:14 PM	#22
Flathead Fever Senior Member Join Date: May 2010 Location: Yucaipa, CA Posts: 1,096	Re: Frustrating start problem First thing to is while trying to crank the engine smack the strarter with a hammer. Hopefully it's not a nice, restored starter. Mi used to working on fleet vehicles where you could beat on them. Sometimes but not always it will start cranking if the brushed are starting to fail. You can do this when they are first failing but eventually the smack test won't work. That was the first thing we did when we know we had battery voltage and an engine would not crank. If it cranks when you smack the starter you can be pretty sure the starter is at fault. If that don't work than this is what you need to do nest, a "voltage drop test" across every switch, cable and connection while you are trying to crank the engine. It will definitely find the bad spot. This is how professional mechanics find those opens and excessive resistance in circuits. It's an easy test to do. I would start with testing across the starter switch, the contacts are could be burned. Resistance is a blockage just like a blocked water pipe. If you were to drill holes in both sides of the blockage in a water pipe you could route the water flow around the blockage. That is exactly what the voltmeter is doing in a voltage drop test. The voltage can't get by the blockage, so it tries to flow through the easier path of resistance through the meter and you see it as voltage reading. There should not be more than .1V to.2V volt drop or there is resistance. Current has to be flowing to do this test. Watch this video and there are many others on voltage drop testing. You must have a voltmeter to work on electrical stuff or you are just guessing. Your starting circuit is much simpler, but the testing is the same. Doesn't matter if its 6V, 12V negative or positive ground this how you diagnose it. https://www.youtube.com/watch?v=WMXE...ENKujYtc&t=633 Last edited by Flathead Fever; 07-22-2023 at 02:31 PM.

07-22-2023, 03:20 PM	#23
rivcokid Senior Member Join Date: Sep 2018 Location: Riverside, CA Posts: 174	Re: Frustrating start problem @Flathead - thanks! I'll print your post out and give that a try too!

09-14-2023, 02:04 PM	#24
rivcokid Senior Member Join Date: Sep 2018 Location: Riverside, CA Posts: 174	Re: Frustrating start problem UPDATE #2 - Well, it finally cooled off enough for me to play with the roadster. I got new battery cables including the copper positive version like the original. I removed both of the old ones, took a wire brush (drill-end kind) to the connection on the frame and transmission, reassembled the system, and it starts like a charm! In fact, it seems stronger too. Now, that said, I started it about 8 times this morning with no problems - but this was intermitant, so the next test is to start it several times over the next few days and see what I come up with. I'm cautiously optimistic, though. Thanks again for all the tips!!

09-15-2023, 03:50 AM	#25
Rob Doe Senior Member Join Date: Apr 2021 Location: Central Illinois Posts: 498	Re: Frustrating start problem rivcokid, x2 on post 22 except for his following description: "That is exactly what the voltmeter is doing in a voltage drop test. The voltage can't get by the blockage, so it tries to flow through the easier path of resistance through the meter and you see it as voltage reading." You can find a description of how to "voltage test" the Model A starting system in Chapter 2 of the blue, Les Andrews "Trouble Shooting and Diagnostics" guide. There are other simple volt meter tests for faulty connections etc. Warning: an ohmmeter cannot be used to find a faulty battery cable or wire. __________________ "It ain't what you know for certain that gets ya in trouble. It's what ya know for certain that just ain't so!"

12-18-2023, 04:50 PM	#26
Rob Doe Senior Member Join Date: Apr 2021 Location: Central Illinois Posts: 498	Re: Frustrating start problem Sponsored Links (Register now to hide all advertisements) deleted __________________ "It ain't what you know for certain that gets ya in trouble. It's what ya know for certain that just ain't so!"

12-18-2023, 05:02 PM	#27
Rob Doe Senior Member Join Date: Apr 2021 Location: Central Illinois Posts: 498	Re: Frustrating start problem Riv, any update on this problem??? __________________ "It ain't what you know for certain that gets ya in trouble. It's what ya know for certain that just ain't so!"