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homemade87 · 10-10-2018, 06:53 AM

The voltometer reads above 12 volts before I try to crank it over. While cranking it drops to almost 0. After it has started it has around 14 volts. Should I try and wrap it in some heat shielding?

This statement you made most likely tells you whats wrong . A battery can read 12.5 volts and still be bad . The plates in the battery sulfates and will not let the current thru them but still show good voltage . The test you did tells you this under load . A battery should not drop voltage that far when cranking . A couple volts at the most if that . Your battery is not up to the task . The 14v tells you the charging system is doing its job . This does not mean the battery is doing its job .

When a electric motor , in this case is the starter gets hot they are less efficient and will not start up under heavy loads when hot when the current is not there to draw from . When cold they may do fine but most likely is on the edge .

Get a new battery regardless . You need to resolve this before going any further . You will be chasing your tail .

10-10-2018, 06:53 AM	#14
homemade87 Registered User Join Date: Apr 2010 Location: Guntersville Alabama Posts: 1,073	Re: Hot starter motor The voltometer reads above 12 volts before I try to crank it over. While cranking it drops to almost 0. After it has started it has around 14 volts. Should I try and wrap it in some heat shielding? This statement you made most likely tells you whats wrong . A battery can read 12.5 volts and still be bad . The plates in the battery sulfates and will not let the current thru them but still show good voltage . The test you did tells you this under load . A battery should not drop voltage that far when cranking . A couple volts at the most if that . Your battery is not up to the task . The 14v tells you the charging system is doing its job . This does not mean the battery is doing its job . When a electric motor , in this case is the starter gets hot they are less efficient and will not start up under heavy loads when hot when the current is not there to draw from . When cold they may do fine but most likely is on the edge . Get a new battery regardless . You need to resolve this before going any further . You will be chasing your tail . Last edited by homemade87; 10-10-2018 at 02:17 PM.