Battery / Starter voltage question

[ymz]

One of our 2003 cars (with over 940,000 km) shows a deep voltage drop while cranking (at -6 degrees C.)... I plugged in one of those cigarette-lighter socket voltage readers, and it goes down to around 8 volts while cranking... I've swapped batteries with the other cars, including a just-about-new (Costco) battery, and the other cars only go down to 10.x volts while cranking... does this mean that the starter in this car is drawing too much power?


Yuri

 

[P2B]

One of our 2003 cars (with over 940,000 km) shows a deep voltage drop while cranking (at -6 degrees C.)... I plugged in one of those cigarette-lighter socket voltage readers, and it goes down to around 8 volts while cranking... I've swapped batteries with the other cars, including a just-about-new (Costco) battery, and the other cars only go down to 10.x volts while cranking... does this mean that the starter in this car is drawing too much power?


Yuri

Starter is the most likely culprit, but could also be bad connections or cables. You would need to check for voltage drops from B+ to starter and B- to block to isolate

Simon

 

[steve6]

^^ Starter is drawing too many powers

 

[iluvmydiesels]

connections / batt posts and grounds is the first and easiest place to check.
a multimeter is usually better for readings. about $20 at sears.
when battery is fully charged, take a voltage reading now. needs to be above 12.5+V. if you have battery charger itd be good. after charging, wait a while and take a battery reading.

 

[ymz]

Battery resting voltage (overnight-cold) is 12.3... I find it curious that the other cars only go down to between 9.8 and 10.3during cranking...



Should I be looking at a replacement starter? (the original one lasted 850,000 km and I put in a used one...)


Yuri.

 

[BobnOH]

Rule out bad connects and any addional mechanical resistance. Then starter, repair or replace.

 

[steve6]

Yuri, in my option, yes you should replace it. or you can order a brush kit and just replace that. Its what I commonly do. I did solenoid and brush kit just before winter and it was lovely how much it revived my starter.

 

[Mongler98]

Clean connections at battery and starter, check for frays. Make sure battery is fully charged overnight, turn on lights for 2 minutes. Now test again. You need a volt meter and you need to test amp draw on the starter main wire. Should be like 140 amps +/- 10%.
As for thebattery, this is cold cranking amp 101. You can still have 12.6v at the battery but only be able to draw fewer amps. My hunch is your battery is probably dead in its capacity to dump amps.

 

[iluvmydiesels]

testing for amps is more difficult. you have to know how to do it. and have a meter that will handle that may amps. if you do it wrong, or dont know how to do it, you ll just blow your multi-meter.
a battery load test is best, and final. however you have to take battery into a shop. costs a few bucks i guess. charge a battery before taking in.
your up pretty far north, these are recent starting attempts, this week and such. whats the temp in the mornings when your doing this? as things have warmed quite a bit here.
do you have the right batteries in your cars. diesels will need 700CCA or more. glow plugs need to work right. bosch glow plugs are normally the best. the relay could be bad, or the GP fuse. do you have your cars otherwise winterized? a 5w-XX synthetic is best. or a 0w. you may need winterizer additive in fuel when filling up. depending on weather report.

the thing you put a used starter in, (after ?original starter? lasted so long) is an indicator. do you still have original starter, you could send to a shop with a kit to get them to refurbish it.

 

[ymz]

I've tried 3 different batteries - fully charged - in this car... all H8 - which should be fine for this engine... Yes, the original starter (we got the car right off the boat - 6 km on it) did last 850,000 km... I looked around the shop and found 2 other used starters, so I guess I'll swap one of them in there...


Thanks...


Yuri

 

[Mongler98]

multimeter with an amp loop is fool proof.
https://www.amazon.com/Aenllosi-Etekcity-Auto-Ranging-Multimeters-voltmeter/dp/B07JLN99XL/ref=sr_1_30?keywords=multimeter&qid=1551481686&s=gateway&sr=8-30
$14 bucks with amazon prime.

this is probably the best tool that you can NOT do with out when you need it and for this price? yea just get the proper tool and never guess again.

 

[Mongler98]

having 8 volts is not necessarily the starter, but it looks like it is. Just dont go spending money on a part to find out it was something else, this has to be the worst feeling in auto work i have ever had.
Make sure you go with an OEM replacement, or rebuild it with OEM parts. The thing most starters fail at is the gear and related area, bearings from over heating but the root of 99% of all those problems is excess heat from higher amp draw due to BAD BRUSHES. It might be as simple as just replacing the brushes and sanding the stator.

 

[ymz]

multimeter with an amp loop is fool proof.
https://www.amazon.com/Aenllosi-Ete...s=multimeter&qid=1551481686&s=gateway&sr=8-30

That's only the case... and that particular meter only measures AC amperage... (I've got one of those...)



In any case, I swapped out the starter for a used one... I'll see what the voltage reads tomorrow morning...


Yuri

 

[Mongler98]

Fine,
ELIKE 3266TA 600A Auto-Ranging Digital Clamp On Meter & Multimeter with NCV,AC/DC Voltage,Resistor,Diode,Continuity https://www.amazon.com/dp/B01C0IYLMM/ref=cm_sw_r_cp_apa_i_-NNECb4MN671D

So a few bucks more but you still get the point.

 

[ymz]

Followup... replacement (used) starter only causes the battery voltage to drop to about 10.4 while cranking, so... I guess I'll send the other one to be rebuilt...


Thanks, everyone...


Yuri


PS: the ultra-low-priced clamp-on multimeters do NOT measure DC amperes... you have to move up a class...
https://www.amazon.com/dp/B0721MKXBC/ref=psdc_14244471_t2_B00NWGZ4XC

 

[Mongler98]

fair enough, i was just clicking links, not shopping for you!
glad you have it sorted. Seems like having a cig lighter voltage gizmo is about the only line of defense against getting stuck someplace with a dead starter. I will be doing this, for this reason, especially since my escape is notorious for eating starters.