grounding issues please help!? im frying throttle cables

[datsun1973]

I just finished swapping a l20b into my 1973 620. Everything works fine except after turning the truck over the first time my gas pedal got stuck. After doing some research on this site I think I fried the throttle cable. The plastic around it was all melted. All my grounds look good except i dont have one from the engine to the body. Is that whats causing the problem? Where do i put the ground from? I didnt see any loose wires off the engine.

[thisismatt]

If you dont have a ground from engine to body then your starter and alternator will draw current through any other means

[MikeRL411]

Been beat to death.  Look at http://community.ratsun.net/topic/53944-need-help-with-an-electrical-issue/ for example.  "Search" is your friend although sometimes it's a bit cranky,  You didn't really "finish" the swap.

[datsun1973]

Thanks for the quick response. I did see that thread my question though is were specifically do i ground the motor from. Is there a specific place on the block that is preferable to ground it from? Thanks again

[Laecaon]

On the head, right behind the fuel pump. Sometimes a lifting loop will be mounted there.

[datsun1973]

Thank you!!!!!

[mklotz70]

On the head, right behind the fuel pump. Sometimes a lifting loop will be mounted there.

and just to be extra clear..... that's the neg batt cable that connects there.  You must have the batt ground cable connected to the body somewhere?

 

There's also another ground between the frame one of the starter bolts.  I would also recommend a ground from the dizzy body to the core support or the coil mount....especially if you're running elect ignition.

[DanielC]

A pickup had four main parts, generally isolated in rubber, so they can move a little bit, THAT MUST HAVE A GOOD ELECTRICAL GROUND TO EACH OTHER.

The engine, the cab, the bed, and the frame.

Additionally, the battery has to have a good connection to the starter, both positive, and negative side.

There should be a ground wire from the cylinder head, the boss just behind the fuel pump down to the frame of the alternator.

There should be a ground wire from the frame of the alternator to the voltage regulator mount.  Even if your truck has been changed to an internally regulated alternator, this wire must still be there, with a good connection to the inner fender of the truck.

 

An electrical connection that looks good tells you nothing.  You need to check the voltage drop across the connection.  For example, take a volt meter, and measure the voltage from the center of the negative terminal on the battery, to the frame of the starter.  You ideally should have a voltage drop of less than .200 of a volt.  Note: there is NOT a decimal point error in that last sentence.

 

More on voltage drop testing here:

http://www.vernco.com/Sparks/id606.htm

[datsun1973]

Thanks again guys!