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What do you do when


Travis
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Well i guess the positive cable isn't the problem starter hit twice today. Out of about 8 starts.

But, I've noticed a pattern.

Back in Oct. When it first started doing this i replaced that starter and it worked great for 2 weeks, i then replaced the solenoid on that starter, it did fine for about 1 week, i then replaced the cheap starter with the Arrowhead starter, it worked good for 1 month , i replaced the cables it works good for about 20 days.... Hmm.

One thing in thinking of doing is ohming the trigger wire.

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Travis,

What is the battery voltage, measured at the; 1) battery posts, not cable terminals); and 2) cable terminals (not the battery posts) when cranking or attempting to crank the engine?

Also, what is he voltage between the +battery post and the +terminal on the starter while cranking/trying to crank it over? (this tests the voltage drop, an indicator of the resistance of all wiring, solenoid contacts, etc between in battery and starter..

In the last, what is the voltage between the − battery post and starter body? (this tests the voltage drop in the ground circuit).

These four simple tests (preferably conducted when the engine does mot want to crank) will assess the condition of the battery terminals, all positive wiring and controls of the starter circuit, and all of the return (ground) path. Post what you observe and we can begin to identify (or rule out) any and all potential electrical issues.

-cliff-

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11 minutes ago, cliffyk said:

Travis,

What is the battery voltage, measured at the; 1) battery posts, not cable terminals); and 2) cable terminals (not the battery posts) when cranking or attempting to crank the engine?

1.   12.75 sitting, drops to 11.90 while cranking, when the starter hits, voltage doesn't drop

2.  12.75 sitting,drops to 11.90  while cranking, when the start hits, the voltage isn't dropping, staying 12.75

 

Also, what is he voltage between the +battery post and the +terminal on the starter while cranking/trying to crank it over? (this tests the voltage drop, an indicator of the resistance of all wiring, solenoid contacts, etc between in battery and starter..

11.90 while cranking

In the last, what is the voltage between the − battery post and starter body? (this tests the voltage drop in the ground circuit).

haven't tested yet

These four simple tests (preferably conducted when the engine does mot want to crank) will assess the condition of the battery terminals, all positive wiring and controls of the starter circuit, and all of the return (ground) path. Post what you observe and we can begin to identify (or rule out) any and all potential electrical issues.

-cliff-

 

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Okay, i ohm'd the wiring in the starter circuit, (trigger wire, wires going to starter relay from key switch, 0 resistance.

Here's something that is very strange though.

 when i first hooked my meter to the battery, it was on auto range, i did +lead to positive post,  - lead to negative post and the meter went to continuity and started buzzing!! WHAT??? continuity between the + AND - posts

battery never has acted weak on start ups in the morning like it's being drained or anything. , charging voltage is showing 13.2 at idle, raising with engine rpm.

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All batteries have an quite low internal resistance. A typical lead acid battery in good condition will have a resistance of 3 to 5 mΩ (0.003 to 0.005 Ω).

The "under load" voltage drop tests I described are much better at identifying poor wiring and connections than any (low current/low voltage) ohmmeter tests. Faulty connections can often measure 0 Ω with a multi-meter but actually have significant resistance under load at high currents like those drawn by a starter motor.

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[quote]

Also, what is he voltage between the +battery post and the +terminal on the starter while cranking/trying to crank it over? (this tests the voltage drop, an indicator of the resistance of all wiring, solenoid contacts, etc between in battery and starter..

11.90 while cranking

[/quote]

11.90 v would be very odd. Are you sure you measured between the + battery post and the + post on the stater? In a perfect world that measurement should be 0.0 V--I.e. no voltage loss between  the battery and the starter.

Note: there is no connection to "ground" or the negative battery terminal in this test. Red lead to the + battery post, the black lead to the +starter terminal. This is somewhat counter-intuitive, however we want to measure the voltage difference between those points--it is an indicator of the circuit resistance.

In the real world 0.2 to 0.5 V would not be unusual, much more than 0.6 to 0.8 V means a bad wire, connection and/or contacts.

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That measurment was taken  from the + on the starter to ground and the + on the battery to ground, same voltage both times, while cranking. that's about the usual amount of drop i get on other small equipment.

you know, thinking back a little bit, i wonder if i ought to try shimming the starter back a little bit, because the way the starter system works, the gear is connected to the solenoid, so when the solenoid pulls back, it pushes the gear outwards, and i wonder if it's too close to the flywheel gear it won't spin to mesh because the gear is hitting so the solenoid can't make the contact to pass power through the starter.

 BUT, if that were the case, why does it work perfect  60% of the time?

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Please make the measurement I described last:

"between the + battery post and the + post on the stater? In a perfect world that measurement should be 0.0 V--I.e. no voltage loss between  the battery and the starter.

Note: there is no connection to "ground" or the negative battery terminal in this test. Red lead to the + battery post, the black lead to the +starter terminal. This is somewhat counter-intuitive, however we want to measure the voltage difference between those points--it is an indicator of the circuit resistance.

 

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6 minutes ago, Travis said:

ah okay, i gotcha. now

You can do similarly with the ground path, black lead to the negative battery post, red lead to the starter body. This indirectly tests the integrity of the ground path--again 0.0 V would be perfect, 0.2 to 0.5 acceptable, more than 0.8 bad... 

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1 minute ago, cliffyk said:

You can do similarly with the ground path, black lead to the negative battery post, red lead to the starter body. This indirectly tests the integrity of the ground path--again 0.0 V would be perfect, 0.2 to 0.5 acceptable, more than 0.8 bad... 

is that with key on or while cranking?

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3 minutes ago, Travis said:

the only thing is my meter will not read voltage going from + to + or - to -.....

i suppose i could check from battery+ to ground while cranking, and then from starter + to ground?

Is it one of those damned auto-function /auto-ranging meters? They often react too slowly and get confused--can it be locked into reading volts?  Preferably in a 0-5 V or so range...

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11 minutes ago, Travis said:

nope, Klein selectable set on DC 20 max

It has to read something--while cranking it should detect at least 0.0 to 0.5 V (0.0 is not likely as that would indicate no resistance in the path--not possib;le in the real world).

Are you 100% certain?

One lead (red or black, doesn't matter) to the + battery post and the other to the + terminal on the starter motor. NO ground or -battery  connection...

Crank  long enough for the meter to stabilse (3 to 5) seconds.

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well apparently my meter will not read voltage when not grounded. Tried with a klein tester and a cheaper chinese one too.

 so what i did  is check voltage at the battery, while cranking, holds at 11.9, same at the starter lug while cranking. and what is happening when the starter gear hits the flywheel, that's preventing the solenoid from closing fully.

but i really don't think it's doing it because of misalignment or something, because when it starts to happen , it seems to do it fairly frequently.

just wonder if sometimes the solenoid isn't getting enough amps through the trigger to completely pull in.

 

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6 hours ago, cliffyk said:

Sometimes just jiggling things about will clear up llightly loose or corroded connections...

i've thought about that, one simple thing i may try  is put a new connector on the trigger wire at the solenoid, since it's the most exposed, and maybe go from there.

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