| Re: High torque starter? [message #326158 is a reply to message #326134] |
Sat, 18 November 2017 23:55  |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma:
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Senior Member |
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There are many things than can cause hard to crank problems. Here are some:
1. If you have changed your vacuum advance from the ported carb fitting to a manifold direct fitting then you have added 10 or more degrees of advance if your foot is not on the accelerator when cranking.
2. Mechanical wear in the stater or Bendix. Usually bushings or brushes / commutator.
3. Low voltage to the starter
3a. Ground cable in wrong location. It goes direct to the block.
3b. Battery in poor condition.
3c. Battery cables in poor condition. Look carefully at the ends inside the crimps for corrosion.
3d. Battery cable connections dirty. They can look clean and still not make good electrical connection.
On mine I had poor cranking speed and cleaned the connections multiple times with a battery brush to no avail. I had decent voltage at the battery. I happened to touch the negative post after cranking and it was warm. Where there is heat there is a bad connection. I had to clean and remove a little bit of lead front the cable connector and the post with a file. That fixed the problem.
The joke is I could have spotted this problem with a voltmeter in minutes. I just never did it. Any connection can be checked by putting the probes across the suspect connection and reading the voltage WHILE CRANKING. It should read ZERO. This can be done on any Positive or Negative path or their component(s). As an example hooking on voltmeter lead direct to the engine block and holding the other lead direct to the negative battery post should read Zero WHILE CRANKING. If not, then go find your bad connection. You can do the same on the positive side. You can also check battery capacity by probing post to post on the battery WHILE CRANKING. It should be in the 11 or high 10 volt range. If you have good numbers there, then check the voltages again at the starter solenoid to engine ground. If there is more the a .2 or .3 volts lower you have a cable or connection problem. The last one I checked WHILE CRANKING in 50 degree weather had about .13 volts loss on the positive cable side and .1 volt loss on the negative side for a total loss of .23 volts at the starter. Re-wiring the positive battery cable direct to the starter should have reduced the loss to .20. For a .03 volt difference I did not bother. .03 volts is hardly worth the effort and expense changing it.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
[Updated on: Sun, 19 November 2017 06:56] Report message to a moderator |
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