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Recently replaced battery cables and now have poor cranking and negative cable gets hot. Starter is new. Battery reads 12v on MM. Bad ground?

If you have a set of jumper cables, try jumping:

- negative on battery to bolt on starter
if that does not help
- positive on battery to positive post on starter
if that dies not work, you might have a bad starter?

foot-actuated starter or electric-solenoid-actuated starter?

Foot starter. Not in position to jump. Going to clean ground on frame and try.

Replaced neg cable without any change. Battery always reads charged at but hardly cranks the engine. Will try new battery tomorrow.

What gauge cables did you use?
6V requires O gauge minimun, OO even better.
If you went with the box store 4 Ga, that's your problem.

"Battery reads 12v on MM."

Sounds like you got a cheapy cable. Sometimes they look good on the outside but are all plastic with too small of wire. If the ground cable hooks to the engine assembly make sure the connection is clean & tight. If it hooks somewhere else make sure there is a good heavy ground cable to the engine. If the bat is strong & the cables are good you could have a bad starter.

OK, you also said that neg cable got hot, did the positive as well? Heat in a cable means one of two things only: the starter drawing to much amperage, or cable is not adequate in some way. Best first check was cable. Was replacement at least 0 as mentioned, and have really good ends? You can run both cables at same time as well. Next is checking out starter. Could try removing and try it with jumpers to a good battery, or take to a parts place or motor shop that can test it.

Replaced neg cable. New battery and fired right up. Previous battery just did not have cranking power despite reading "charged" on the battery tender. Thanks for all advice!

Also ensured good ground to frame with wire brush.

I do not like the way GM wired the ground wire to the frame next to the battery, then from the frame to the engine block. Its one too many extra places for rust to occur.
I use a longer ground cable from the battery to the frame where the woven ground strap is which goes to engine.
Carl

It is a 12 volt. Not sure of the gauge of the new cable but will check.

Wouldn't it be better to attach that long cable directly to the engine, or maybe a bellhousing bolt? Then use a ground strap to the frame and/or the cab to handle such things as grounding the lights, voltage regulator, etc.

Another one between the bed and the frame helps with tail lights, turn signals, and such. There's no such thing as having too many grounds!
Jerry

On my 6v Suburban, I have ground straps from the frame to the clutch housing on both sides of the engine. Also, a ground strap from the head to the firewall (GM spec for radio).

And, just to be safe, I run the 00 ground cable from the negative terminal on the battery directly to a starter mounting bolt (instead for the strap/cable from bettery frame.

My only weak grounds are for some lamps/bulbs, where a screw into sheet metal provides the ground (I failed to expose metal through the epoxy/urethane layers in sheet metal/etc).

Wow, surprised about the ground issue. I am installing a radio what would be the best way to ground that? I have a 12 volt 1/2 ton. THanks, Scott

Grounds are like the sewer or septic system in a municipal water supply- - - -they get the water back into the earth it came from. Ditto for auto electrics- - - -the electrons need a low-resistance path back to the battery to complete the circuit.
Jerry

Yes it would. That is exactly what I did on my '49 with a 350 in it. On my '50 (with a 235), I didn't want to lose the original look of the woven ground strap between the frame and the bellhousing bolt.

" . . . a ground strap from the head to the firewall (GM spec for radio) . . . "

I run a strap from the rearward coil mounting bolt/screw to one of the the passenger side fender-to-firewall bolts. The dash is connected to firewall, and the radio is connected to the dash. Presumably they will be bare-metal to bare-metal contact providing ground-continuity?

Here is a ground question.(pertaining to lighting protection)

You have a TV antenna on the top of your roof.
There is 20 feet of coaxial cable coming from the TV antenna going down the siding to a coaxial cable ground block.
From the coaxial cable ground block there is 20 feet of coaxial cable that is going into the home and is connected to the back of the TV.
Also from the coaxial cable ground block there a single 19 foot, 10 gauge copper
ground wire that is connected to a 10 foot ground rod that is pounded into the ground.
The antenna mast is also grounded to the ground rod with 39 feet of 10 gauge copper ground wire.

If the TV antenna gets hit by lighting, is the TV protected?

Don't make any big bets on it. Millions of volts pushing thousands of amps at the speed of light has a tendency to overpower any sort of grounding system. When we were the last residence at the end of the power grid in our neighborhood we lost two deep well submersible pumps to lightning strikes. It seems the power surge from lightning hitting a transformer half a mile away on top of a tall hill liked a wet ground 300 feet deep with my pump hanging on the end of a pipe, and the pipe was plastic! No wiring damage, no tripped circuit breakers, just motor windings fused into a solid blob of burned copper!
Jerry

I have surge protectors on my TV for that but they are no guarantee either but I figure they can't hurt.

Dennis

by the way, I used a 4 gauge ground strap.

Jerry, There is a 'trick' which may save your pumps in the future. I learned it when putting in earthquake monitoring systems for TVA. We had to to install the seismonitors on ridges due to us having to use 'line of sight' data transmission. Lighting would hit the solar panel or antenna and wipe out the electronics.
Learned to put a 'J' shaped loop in the coaxial and solar panel wire underground when it entered the electronic box. As lighting is moving at near the speed of light it tends to want to run straight. It would hit the 'J' curve and burn a hole through the insulation to reach ground. We also installed "Zapnots" on the front end of the electronics for the reduced electromagnetic spike. Yeah, we would lose a coaxial cable but not thousands of dollars of electronics.

When the power company rewired the system in the neighborhood the last time an ice storm took all the lines down, we're no longer at the end of one circuit. No problems recently, other than when one of the neighbors spits a chaw of tobacco off his back porch, the moisture shorts out the power grid! The Fayetteville electric system is notorious for having rain and thunderstorm outages! Those kerosene lamps in various places around our house are not decorative. We keep 'em filled with oil and the wicks trimmed all the time.

It's a small price to pay for being 20 miles from the nearest town big enough to have a WalMart and public housing, though!
Jerry