Starting question 73 1.7 |
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Starting question 73 1.7 |
rosenfe |
Jun 7 2024, 03:17 PM
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#1
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Senior Member Group: Members Posts: 564 Joined: 14-October 13 From: northern california Member No.: 16,512 Region Association: None |
When I turn key I get intermittent response from starter. Sometimes nothing, other times barley cranks. Rebuilt starter from bruce. New battery jumping posts with key on or off only spins starter motor. Bad starter?
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Ishley |
Jun 7 2024, 03:50 PM
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#2
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Member Group: Members Posts: 148 Joined: 4-October 21 From: Clarendon Hills Il Member No.: 25,957 Region Association: Upper MidWest |
Start with the basics… is the transmission ground strap connected and giving a good ground?
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rosenfe |
Jun 7 2024, 03:53 PM
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#3
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Senior Member Group: Members Posts: 564 Joined: 14-October 13 From: northern california Member No.: 16,512 Region Association: None |
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emerygt350 |
Jun 7 2024, 04:03 PM
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#4
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Advanced Member Group: Members Posts: 2,470 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
Jump the solenoid not just the starter. Does that work?
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rosenfe |
Jun 7 2024, 04:07 PM
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#5
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Senior Member Group: Members Posts: 564 Joined: 14-October 13 From: northern california Member No.: 16,512 Region Association: None |
I’m jumping the two posts
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Ishley |
Jun 7 2024, 04:24 PM
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#6
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Member Group: Members Posts: 148 Joined: 4-October 21 From: Clarendon Hills Il Member No.: 25,957 Region Association: Upper MidWest |
Battery good and charged? I assume if you got it from Bruce the starter was checked and is good… sounds like a power or solenoid issue. Is the supply positive good and connection is good?
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rosenfe |
Jun 7 2024, 04:48 PM
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#7
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Senior Member Group: Members Posts: 564 Joined: 14-October 13 From: northern california Member No.: 16,512 Region Association: None |
I’ve been jumping wrong part on starter. Should be positive lead to spade terminal. Now starter engages. I will test voltage of switch at starter. Pretty sure it’s a bad switch
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emerygt350 |
Jun 7 2024, 05:22 PM
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#8
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Advanced Member Group: Members Posts: 2,470 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
It could just be the normal "time to put a Ford solenoid on there". The original is picky about 12v. Google it. I will be heading for the door before the purists get here....
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SirAndy |
Jun 7 2024, 05:32 PM
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#9
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Resident German Group: Admin Posts: 41,854 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
It could just be the normal "time to put a Ford solenoid on there". The original is picky about 12v. Google it. I will be heading for the door before the purists get here.... IMHO, running a relay is a good idea regardless. There's really no need to run all that current through the starter switch. (IMG:style_emoticons/default/popcorn[1].gif) |
Superhawk996 |
Jun 8 2024, 12:16 PM
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#10
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914 Guru Group: Members Posts: 6,502 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
It could just be the normal "time to put a Ford solenoid on there". The original is picky about 12v. Google it. I will be heading for the door before the purists get here.... Ya’ gotta laugh how the solution is always to add weight to a 914 (IMG:style_emoticons/default/lol-2.gif) |
emerygt350 |
Jun 8 2024, 12:18 PM
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#11
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Advanced Member Group: Members Posts: 2,470 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
That Ford part probably adds at least 5 HP...
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Superhawk996 |
Jun 8 2024, 12:23 PM
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#12
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914 Guru Group: Members Posts: 6,502 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
Start with the basics… is the transmission ground strap connected and giving a good ground? Yes. I checked grounds How? You cannot tell the quality of a ground cable just by visual inspection. The most reliable way to verify a ground cable is measure the voltage drop across the cable while simultaneously cranking. This is because you’re trying to measure less than 1 ohm of resistance which many cheap o’ multimeters will struggle to do. |
Superhawk996 |
Jun 8 2024, 12:23 PM
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#13
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914 Guru Group: Members Posts: 6,502 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
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Superhawk996 |
Jun 8 2024, 12:28 PM
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#14
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914 Guru Group: Members Posts: 6,502 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
Good reading regarding how to measure and judge acceptable voltage drop across a ground.
https://www.fenderbender.com/running-a-shop...ircuits-part-11 The most misunderstood aspect of the stater is that it typically draws 50-100 amps of current while cranking. This is in addition to the 25 amps of current that the Bosch starter solenoid needs to draw to pull in and operate the actual motor correctly. It only takes a minute amount of resistance in the ground cable to cause HUGE problems due to the high current draw. As an example .01 ohms of resistance in a ground cable will drop 1.25 volts (way too much) if drawing 125 amps of current while cranking. |
dtmehall |
Jun 8 2024, 08:38 PM
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#15
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Newbie Group: Members Posts: 35 Joined: 21-December 23 From: Farmington Hills, Michigan Member No.: 27,808 Region Association: Upper MidWest |
Good reading regarding how to measure and judge acceptable voltage drop across a ground. https://www.fenderbender.com/running-a-shop...ircuits-part-11 The most misunderstood aspect of the stater is that it typically draws 50-100 amps of current while cranking. This is in addition to the 25 amps of current that the Bosch starter solenoid needs to draw to pull in and operate the actual motor correctly. It only takes a minute amount of resistance in the ground cable to cause HUGE problems due to the high current draw. As an example .01 ohms of resistance in a ground cable will drop 1.25 volts (way too much) if drawing 125 amps of current while cranking. |
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