53 flathead slow crank

1953 merc flathead 255. good battery has ran recently but i went to start today and it cranks very slow and wont start also neg cable gets hot but that may be due to me cranking on it so much.

 

poor connection at battery, or starter, or ground. Clean the battery first, then the others.

 

I've got the same set up and had this problem a lot. I ended up having to recharge my battery and clean it pretty much constantly. I ended up replacing my battery terminals and investing in a battery tender and the problem went away.

Then again this is the same car that tore through 5 generators in a year so by this point I was pretty sick of putzing with getting it started.

 

How heave is the ground cable

 

Diagnostics: Hot cable is almost certainly too small in gauge and is hot because of resistance. Replace with BIG one.
Heat is a good general indicator of resistance...a hot solenoid likely has fried contacts, and sometimes you will actually hear sizzling and see smoke at a bad terminal connection.
Battery cables should be large gauge, and even larger if 6 volt! General parts store ones are small even by 12V standards.
Add a cable from battery ground connection on firewall direct to starter bolt, bypassing all kinds of paint, rust, and dirt on ground side.
All fomoco with generator should have G post on gen wired right to regulator base and a jumper added over to that same fireall connection.
Kill off all the resistance points and that sucker will start serious cranking.
Rule of survival: Anything electrical that is hard to figgerout will eventually prove to be a ground problem.

 

when was the last time the grounds were cleaned? maybe its getting time to clean the connections