The Stovebolt Site Forums The Shop Area The Electrical Bay Ode to an intermittent Runtz

Oh runtz, oh runtz, why do you act this way
you work for a while, then you've nothing to display
I don't know what I did to you to make you act this way
intermittent runtz, you make me pull my hair
I've worked on you for so long you make me want to swear
your connections fine, your ground is good
but still you give me grief
one day you will not work the next you are a relief
intermittent runtz I don’t know what to say
I think I'll ask the stovebolt guys, why you just won't work all day

I'm not a poet but it sounds to me like you have a short or a crack in the little circut board. I would contact the place you bought it and get a replacement. If your connections are good and it works intermitently you have a faulty unit.

Good Luck
George

Crow; try www.speedwaymotors.com 12 to 6 volt reducers.There a two types of voltage reduces.One is for eletronis devicies such as your gauges.This is transistorized and we call in the Runtz.You need one of these for each electric gauge on your car.The other reducer is the ceramic block style which is used ONLY for your fan motor.NEVER,EVER use the ceramic block version for gauges,radios or lighting as the power surge,when first turned on WILL DESTROY THE ELECTRONICS! Free Catalog page 132 street rod catalog. hope this solves you problems.

Ok sorry for the vacation guys but i have been like the one armed paper hanger these past months....shop expansion and related....

As for the part time Runtz.... The Runtz has a built in circuit protection to protect the dash gauges from voltage spikes and shorts in wiring harnesses. If the Runtz detects a voltage spike it will shut down like a fuse until things cool down then will come back. It will do that about 4-5 times before it acts like a fuse and stops the flow of current completly.

This case sounds like enough of a voltage spike to just barely trip the Runtz.

That is why it is important to be sure the power to the ignition switch comes directly from the battery post of the battery and not from the amp gauge or starter solenoid as per original.

When the starter switch is closed to crank the engine a voltage spike is created that travels thru the electrical system ....about 300 volts worth. By powering the dash gauges thru the battery, the battery will "eat" those voltage spikes and protect the dash gauges from the voltage spikes.

This is important because the Runtz is a solid state device and is very accurate. If you notice most new positive battery cables already have a 10 gauge wire moulded into the battery clamp. That is what that wire is for.....to power the ignition.

All of this is also true for things like cell phones plugged into cigar lighters, and modern stereo radios... all need to have direct battery power.

Have you seen modern radios installed in old cars and soon after the LED lights are burned out and you cannot figure out what station they are on? A voltage spike is what took out the LED lights and soon ennough the radio itself will be next.

So the important lesson here is be sure the power to the ignition switch and any solid state accessories comes directly from the battery....
Class dismissed....
Randy

I have been running a Runtz in my resurrected '51. The alternator is a delco 10SI. I have a #8 copper wire running from the alternator to the starter battery terminal, so I am not using the ammeter for anything but a power distribution point.

The sender never has read correctly (read 1/4 tank when tank is dry) and has been erratic at times. The fuel gauge quit recently (read empty all the time) so I installed a new sender. The gauge did not work so I 'ohmed' the sender and it reads correctly (30 ohms @ full, 0 ohms @ empty). I then traced the circiut and figured out that the Runtz was not putting any voltage.

What typically goes wrong with these units after 'voltage spikes'? How can I fix this voltage reducer so my gas gauge works again?

Racecarl,

If the Runtz is solid state, and it fizzles, I think it is non-repairable. You can pick up a small voltage reducer that will work with your fuel gauge for under two dollars...at that price, I wouldn't spend much time with the Runtz that went south.

Stuart

I just read a post by a guy named crow,
What he's talking about I really don't know;
Something about a faulty Runtz,
Sounds like maybe it's making shunts;
I do know he came to the right place,
These guys are better than the guys at "Ace";
They'll get him back on the right path,
So his "bolt" won't have to feel his wrath;
You wanna know why I'm talking this way?
Cause I'm just excited about a Chevrolet!!
Burma Shave