Hot cutout on 36 ford

[zoegrant]

A question....Should the cutout on top of my generator on my 36 feel hot to the touch, approx. 150 degrees according to my heat sensor gun. ????????

I had just replaced it as my other had died, the points on the old one actually fused together. I suspected that the Battery wire screw had shorted against the case.

[ford38v8]

It's doubtful you'll find anything under the hood to be less than 150º F.

[zoegrant]

How does the cut out actually work ?

[Kube]

Zoe,
I'm thinking there's a charging issue / short somewhere in your circuit(s).
For a comparative test, I just took out my '36 roadster - 100% STOCK. It is 86° here currently. I ran it to the grocery store, 7.8 miles from here. Parked, bought a few items, got back in, started up immediately and drove home. (hmmm.. no vapor lock, no electric fuel pump and 10% ethanol fuel).I guess I must be doing something wrong...
Anyway, drove the 7.8 miles home, parked in the garage, shut it off and carried in the groceries. Went back after about five minutes, allowing the temps to rise after shutting it down.
Here's what I got, all in Fahrenheit:
Cylinder heads 126° - 137°
Intake manifold 134° -136°
Starter body 110° -116°
Carburetor 109°
Fuel pump 106°
Water pumps 135° - 141°
Generator 105°
and lastly: cut out 116° - 117°

[JSeery]

Originally Posted by zoegrant

How does the cut out actually work ?

It acts like a relay to prevent battery current from flowing back into the generator at very low rpms or with the engine stopped.

[V8COOPMAN]

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Originally Posted by Kube

Zoe,
I'm thinking there's a charging issue / short somewhere in your circuit(s).
For a comparative test, I just took out my '36 roadster - 100% STOCK. It is 86° here currently. I ran it to the grocery store, 7.8 miles from here. Parked, bought a few items, got back in, started up immediately and drove home. (hmmm.. no vapor lock, no electric fuel pump and 10% ethanol fuel).I guess I must be doing something wrong...
Anyway, drove the 7.8 miles home, parked in the garage, shut it off and carried in the groceries. Went back after about five minutes, allowing the temps to rise after shutting it down.
Here's what I got, all in Fahrenheit:
Cylinder heads 126° - 137°
Intake manifold 134° -136°
Starter body 110° -116°
Carburetor 109°
Fuel pump 106°
Water pumps 135° - 141°
Generator 105°
and lastly: cut out 116° - 117°

Originally Posted by ford38v8

It's doubtful you'll find anything under the hood to be less than 150º F.

Hmmm.....Those Kube temps from his '36 roadster don't seem to be anywhere near that 150°F figure. WTF, over? Factual data is usually way-mo-better than supposition and WAGs. DD

[V8COOPMAN]

Originally Posted by Kube

I'm thinking there's a charging issue somewhere in
my '36 roadster - 100% STOCK. I ran it to the grocery store, 7.8 miles from here. Parked, bought a few items, got back in, started up immediately and drove the 7.8 miles home, parked in the garage, shut it off. I guess I must be doing something wrong.

Well duh! Maybe you need to question your thinking here. Didn't you know....I was just reading somewhere that you must drive a 6v vehicle for ten miles at highway speed to sufficiently replenish ALL the sparks in your battery that you use-up during each "start". DD

[flatheadmurre]

A current meter is you friend in this case...it will verify if you have a high current going out of the generator that will kill your points and create a raised temp while doing it.
When you have verified if the current is normal or not...then you can continue to search for a problem.

[Bill OH]

And you can also connect a voltmeter across the generator output and the battery terminal on the cutout to determine if you have a voltage drop in the points of the cutout when the engine is say running 1500 rpm. Set the voltmeter on at least the 10 volt scale. At 1500 rpm there should be negligible reading. At engine idle, the voltmeter should show battery voltage. This test will indicate the condition of the cutout points. Make sure the connections on the cutout are CLEAN AND TIGHT.

[Kube]

Originally Posted by V8COOPMAN

Well duh! Maybe you need to question your thinking here. Didn't you know....I was just reading somewhere that you must drive a 6v vehicle for ten miles at highway speed to sufficiently replenish ALL the sparks in your battery that you use-up during each "start". DD

Yeah, I'm thinking that thread about driving ten miles to replenish your battery was the one on the Early Ford Club site. Am I correct?
I found it difficult to believe there are some folks that truly think they need to drive their Ford a minimum of ten miles at HIGHWAY speeds to replenish the battery just from the drain of starting.
I mean YIKES! Just how long does it take these guys to get their cars to start? Maybe that's the issue? Their cars are not set up properly?
Of course there are those that believe nearly everything under the hood is 150°+. Probably the same guys that have to crank their engines over (too) long to get them to start.
I say if under the hood is 150°+ all over the place, yeah, they probably have vapor lock.
I also say they need to repair their vehicles properly so they start rapidly and run cooler.
I suppose these days it's easier to blame ethanol fuels, poorly constructed batteries, etc. rather than actually go to the trouble and expense to fix their vehicles properly. These old Flatheads are not all that difficult to figure out...

[rotorwrench]

Battery condition has the most affect on how the generator works since it controls the voltage in the system. A high resistance connection on the battery can over tax the generator. The one thing about a stock 3-brush generator is that it will put out a constant current all the time whether it's needed or not. The current output is adjustable with the 3rd brush. Perhaps it is set too high but a bad battery connection could also be a problem.

[Kerk]

I lost 2 Amp meters on a 32 ford when the points in the cut out stuck Closed when I shut the car OFF.. I would only use a Funspot cut out after that ! JM2CW kerk

[Terry,OH]

How does the cutout work?? When the engine stops the contacts in the cutout open and prevent the battery from discharging through the generator. When the engine starts and the generator produces volts and amps the cut out picks up to close the contacts allowing the generator to charge the battery. The cut out does not limit current or regulate it. That is done by the "third" brush in the generator and the battery.

[rotorwrench]

The residual magnetism left from the polarizing of the field is what allows the generator to work up enough voltage for the electro-magnetic core in the cut out to close the switch points and bring the generator on line. If these points should get stuck together due to excessive heat or poor condition then the generator will try to motor after the engine is shut down. This will burn up the generator since it doesn't have the torque to turn the engine. It will just sit there and get hotter and hotter till something fails. The solder in the armature will usually melt first.

Original cut outs may have the cap spot welted on from underneath. The spot welds can be ground till the cap will release. With the cap off, the points can be dressed and the magnetic pole condition can be evaluated. These cut outs can be repaired as long as they aren't toasted.

[koates]

Originally Posted by Kerk

I lost 2 Amp meters on a 32 ford when the points in the cut out stuck Closed when I shut the car OFF.. I would only use a Funspot cut out after that ! JM2CW kerk

Funspot should read as FUN PROJECTS which is a regulator not just a cut out. I have fitted several of these units and they work very well provided the enclosed instructions are followed correctly. Apparently not in stock at the moment. The company has changed hands. Regards, Kevin.