[docnash]

Have a 46 Ford half ton with late model flathead V-8. Six volt system with positive ground. Rebuilt starter, new battery, charges well, runs real good but cranks very very slow. Have checked cables and ground. Could this be a solenoid problem or starter button. ?? Thanks for any suggestions
.

Doc

[docvette]

Doc here,

Welcome to the Forum!

Be sure your Ground cable is grounded at or near the starter..and the proper gauge.

The solenoid Could be a problem, whereas the "Contact Shoe" inside the plunger assembly may be pitted or burned..Have a load test done at the local Auto Zombie (freebie!)

The Bearings may have been damaged in the starter rebuild, does it spin up fast on the bench? OR if you take power directly to the power tab for the motor ? (Bendix not activated) If not, pull it down and reinspect it and brush contact on the armature, AND burnish the armature with Emery paper until shiny..and the bearings..

Inspect the winding solder joints..you may have a cracked or cold one.

Inspect the Bendix for slow (binding ) operation..

That should give you some direction..

Doc

[rj57]

Be sure your Ground cable is grounded at or near the starter...

So this can affect how a 6 volt system operates under load?

I ask cause my father owns a '49 Dodge pickup that cranks so slow, you'd swear you're going to have another B-day before the engine starts.

New battery cables, new battery, but the Ground (positive) cable is mounted to the transmission on this truck. No where near the starter.

[docvette]

Originally Posted by rj57

So this can affect how a 6 volt system operates under load?

I ask cause my father owns a '49 Dodge pickup that cranks so slow, you'd swear you're going to have another B-day before the engine starts.

New battery cables, new battery, but the Ground (positive) cable is mounted to the transmission on this truck. No where near the starter.

Doc here,

You ALWAYS want to deliver the Maximum current from the SOURCE (Battery ) to The LOAD (starter Body), No matter what the voltage or polarity is..

The farther current has to travel , the more resistance it encounters..The more resistance it encounters, The more heat it produces..(current doing NO useful work or wasted energy)....The more swamped the end user device becomes..Less current available to do useful work.

To simplify..

If you have a 4000 lb car , going from point A to point B..and the choice of two routes , C and D...Route C is 100 mles...Route D is 10 miles..which route is going to produce the most work, with the least amount of fuel expended?

Electricity is no different..

Doc

[docnash]

Many thanks for your help. Will pull starter again and bench test. Worked on flatheads many years but never had this problem. Will test solenoid but usually when they go bad, they won't carry any load. At least that has been my experience. Have had a starter button that was corroded and had similar effect but I have checked that. Battery cables are not stock for this application , so there is another avenue to explore. Thanks again...I will be back and post the solution.

Doc