Bad voltage regulator

[Dwd14329]

My 1947 2N was running great after new carb, distributer, plugs and wires, coil, and cleaning out gas tank and filters. I have very good gas flow thru carb. I changed oil and added sea foam to fuel tank for winter and plugged in a battery maintainer.

My issue: I started up tractor, purred like a kitten for a couple minutes, then started running as if the tractor was running on half cylinders, after a minute or so it started purring like a kitten again then started running bad again. Same cycle! I pulled plugs and they are completely fouled. I will replace plugs to see what happens but my questions is how plugs fouled? I ran tractor off and on in summer and it ran beautiful. My tractor was converted to 12v system by previous owner. I've owned it less than a year, so my question is, can a voltage regulator cause my problem? How can I test my voltage regulator? I will be testing battery voltage with a tester while running tractor after I change the plugs today but I cant figure out why this suddenly happened. Any incites? Can it be the voltage regulator and how can I know for sure if it is? I'm not a certified mechanic and don't understand the connection between the voltage regulator and firing sequence but I'm open to advice. Does the voltage regulator feed constant voltage to distributer, points, etc.. ? As you can tell, im obviosly not a mechanic. Please advise! Thanks

 

[Bruce (VA)]

The voltage regulator is in the charging circuit and not in the ignition circuit. Your voltage regulator has nothing to do w/ your stated problem.

Chances are anyway that you have an alternator w/ an internal voltage regulator.

Check all the connections in the ignition circuit, starting with each plug wire at the plug and cap as well as the coil wire, ignition switch, resistor, etc.
75 Tips

 

[Abbby]

Maybe you have a sticky float?

 

[Steve A W]

Read Bruce's 75 tips.
There's a lot to be learned there.

 

[Dwd14329]

(quoted from post at 06:21:25 12/09/23) Maybe you have a sticky float?

Would a sticky float foul out plugs? Trying to understand, if float was stuck open then I would have excess fuel causing rich burn at plugs, correct? It would make sense as to why suddenly my plugs are fouled. Please advise. I gather from Bruce that the regulator is not my issue so fuel must be my problem.

 

[Eman85]

Voltage regulator doesn't sound logical but if you have a voltmeter hook it to the battery and take readings with the engine off and then with the engine running. As someone stated you most likely have a GM style alternator with an internal voltage regulator.
How much Seafoam did you add to the tank? How long has the tractor been sitting? Might want to drain and refill tank with some non-ethanol gas or hook a remote tank up and see how it runs.

 

[Bruce (VA)]

You do not have a v/r problem. You could have either a fuel or electrical problem.

You most likely do not have a sticky float, but you could easily have a sticky needle valve. Same symptoms, but floats usually work or they don't.


Check the wiring first. It's easy. Put some Seafoam or MMO in the tank to clean up a potential sticky needle valve.

Post back w/ results.
75 Tips

 

[Jim L WA]

You said, My 1947 2N was running great after new carb......
There might be your problem. New carburetors from the land of almost right have a poor reputation. What was wrong with your old one? I would put it back on and see how it runs. Let us know.

 

[Dwd14329]

(quoted from post at 09:07:58 12/09/23) Voltage regulator doesn't sound logical but if you have a voltmeter hook it to the battery and take readings with the engine off and then with the engine running. As someone stated you most likely have a GM style alternator with an internal voltage regulator.
How much Seafoam did you add to the tank? How long has the tractor been sitting? Might want to drain and refill tank with some non-ethanol gas or hook a remote tank up and see how it runs.

I added recommended amount of seafoam to 10 gallons of gas. A little less in fact. I changed plugs and again it ran good for a couple minutes then started puttering as if starving for fuel or miss firing. Checked all plug wires as advised from Bruce and disassembled carb to see if float was free and all looks good. I did check voltage and voltage on battery at 13v before running then drops to 12 volts after started. Is it possible the Delco alternator is bad? I also inspected and tightened all connections. A couple slightly loose connections but it didn't appear to correct the issue. This tractor was running great, just boggles me. Doesn't it sound like it could be pin pointed to just one thing? I couldn't locate a physical voltage regulator on the tractor so I'm assuming you are correct with alternator having internal regulator.

 

[Dwd14329]

(quoted from post at 09:07:58 12/09/23) Voltage regulator doesn't sound logical but if you have a voltmeter hook it to the battery and take readings with the engine off and then with the engine running. As someone stated you most likely have a GM style alternator with an internal voltage regulator.
How much Seafoam did you add to the tank? How long has the tractor been sitting? Might want to drain and refill tank with some non-ethanol gas or hook a remote tank up and see how it runs.

I added recommended amount of seafoam to 10 gallons of gas. A little less in fact. I changed plugs and again it ran good for a couple minutes then started puttering as if starving for fuel or miss firing. Checked all plug wires as advised from Bruce and disassembled carb to see if float was free and all looks good. I did check voltage and voltage on battery at 13v before running then drops to 12 volts after started. Is it possible the Delco alternator is bad? I also inspected and tightened all connections. A couple slightly loose connections but it didn't appear to correct the issue. This tractor was running great, just boggles me. Doesn't it sound like it could be pin pointed to just one thing? I couldn't locate a physical voltage regulator on the tractor so I'm assuming you are correct with alternator having internal regulator.

 

[Dwd14329]

(quoted from post at 09:07:58 12/09/23) Voltage regulator doesn't sound logical but if you have a voltmeter hook it to the battery and take readings with the engine off and then with the engine running. As someone stated you most likely have a GM style alternator with an internal voltage regulator.
How much Seafoam did you add to the tank? How long has the tractor been sitting? Might want to drain and refill tank with some non-ethanol gas or hook a remote tank up and see how it runs.

I added recommended amount of seafoam to 10 gallons of gas. A little less in fact. I changed plugs and again it ran good for a couple minutes then started puttering as if starving for fuel or miss firing. Checked all plug wires as advised from Bruce and disassembled carb to see if float was free and all looks good. I did check voltage and voltage on battery at 13v before running then drops to 12 volts after started. Is it possible the Delco alternator is bad? I also inspected and tightened all connections. A couple slightly loose connections but it didn't appear to correct the issue. This tractor was running great, just boggles me. Doesn't it sound like it could be pin pointed to just one thing? I couldn't locate a physical voltage regulator on the tractor so I'm assuming you are correct with alternator having internal regulator.

 

[Dwd14329]

I actually did try the previous carb after I rebuilt it to specs. Both are aftermarket. Same issue

 

[Dwd14329]

Bruce,
I put a voltage meter on battery, read 13 volts, started engine and slowly dropped to 12volts. Is that enough voltage? Should I have the alternator tested? Can a bad alternator cause my symptoms?

 

[R Geiger]

(quoted from post at 13:28:21 12/09/23)
Bruce,
I put a voltage meter on battery, read 13 volts, started engine and slowly dropped to 12volts. Is that enough voltage? Should I have the alternator tested? Can a bad alternator cause my symptoms?

he voltage should go up to around 14 when running. I would have the alternator tested.

 

[Dwd14329]

(quoted from post at 12:36:24 12/09/23)

(quoted from post at 13:28:21 12/09/23)
Bruce,
I put a voltage meter on battery, read 13 volts, started engine and slowly dropped to 12volts. Is that enough voltage? Should I have the alternator tested? Can a bad alternator cause my symptoms?

he voltage should go up to around 14 when running. I would have the alternator tested.

I understand that to be correct, 14v when running. Here's my question. Can low voltage cause missfiring? Am I correct by saying if correct voltage is not present at the spark plugs, they will not fire correctly? Could that be what is fouling my plugs? I will obviously have alternator tested. If replaced can my issue be resolved or do I have another fuel issue internally in carb? I have very good fuel flow through carb. I pulled plug at the bottom of carb and flowed out very good. I'm getting mixed views as to whether the altenator has anything to do with firing, or the ignition system. I'm going to drain the fuel tank and add low ethanol fuel to see if that resolves my issue. I have not changed anything and the tractor ran beautifully all summer. All I did was add recommended amount of seafoam.

 

[Dwd14329]

(quoted from post at 10:17:17 12/09/23) You do not have a v/r problem. You could have either a fuel or electrical problem.

You most likely do not have a sticky float, but you could easily have a sticky needle valve. Same symptoms, but floats usually work or they don't.


Check the wiring first. It's easy. Put some Seafoam or MMO in the tank to clean up a potential sticky needle valve.

Post back w/ results.
75 Tips

Bruce

I checked all ignition circuit wiring and tightened all connections. Plug wires look good. I added seafoam to previous tank. I just drained tank and put fresh fuel in tank. Seems to be running better except that it's not idling good. It wants to ramp up and down slightly between approx 200 rpm range. This missing appears to be gone after running fresh fuel for about 10 minutes. Any thoughts on inconsistent idle?

 

[used red MN]

In reply to your question of the affects of the alternator
charge on the ignition. I think that the battery voltage
would have to get below the level that the machine
would no longer start off the battery to have any
problems with the plugs firing. I have a Farmall M that
is a family tractor that I resurrected. In the course of
getting it running the wiring to the generator was bad
so I wired in a lead for an alternator and taped it back
but have since never installed the alternator. The
generator is there turning along but it has no wires
connected to it. There is a resistor on the original 6
volt coil to give the coil circuit the proper resistance. I
have just used it with a 12 volt battery sat on it. It will
easily start it the tractor two to three dozen times or
more. I am sure you realize during that time the battery
voltage is dropping. I have never experienced any type
of misfiring from the lower battery voltage. Now I
realize that different coils may react to low voltage
differently but I doubt it would be much different from
the ignition on my Farmall.

 

[Dwd14329]

That helps, thank you, used red MN. My miss information came from Google. It would make sense if I had a computerized ignition system that voltage might have an effect on coils but not in this case. I have a 12v system but may have to replace the altenator before it gets too bad. I've always read at least a little over 13v on the battery after starting any vehicle with a charging system. My concern is the voltage I'm getting at the battery after starting is only 12v, no higher! And it makes sense that 12 volts would not have an effect on firing. I'm not sure if you read previous posts but I took the advice of tips given and drained fuel tank and replaced with non tanted fuel. Maybe this old tractor didn't like the seafoam. Who knows?? It seams to be firing smoother but now I have an inconsistent idle. Wants to ramp up and down consistently as if searching for the correct idle speed. I don't know if the governor would have anything to do with idle but when I speed up the rpms it runs smooth. Any ideas?

 

[Factotum]

If you have one, try switching out the ignition coil. Sounds like it is firing intermittently when it warms up.

 

[Eman85]

(quoted from post at 05:13:10 12/10/23)
That helps, thank you, used red MN. My miss information came from Google. It would make sense if I had a computerized ignition system that voltage might have an effect on coils but not in this case. I have a 12v system but may have to replace the altenator before it gets too bad. I've always read at least a little over 13v on the battery after starting any vehicle with a charging system. My concern is the voltage I'm getting at the battery after starting is only 12v, no higher! And it makes sense that 12 volts would not have an effect on firing. I'm not sure if you read previous posts but I took the advice of tips given and drained fuel tank and replaced with non tanted fuel. Maybe this old tractor didn't like the seafoam. Who knows?? It seams to be firing smoother but now I have an inconsistent idle. Wants to ramp up and down consistently as if searching for the correct idle speed. I don't know if the governor would have anything to do with idle but when I speed up the rpms it runs smooth. Any ideas?

Is this a single wire alternator? Did you check voltage after revving engine? Many 12v conversions with a single wire alternator need the alternator to reach a certain RPM before they get excited to charge.