99 Sub Slow Cranking.

[HammerWerf]

Folks,

RE: 99 Suburban

Learned of a new starter issue last night. Engine Turned over kinda slow, but fired up. We just got the truck back from the shop last week, after they replaced the IP. Checked the battery connections, found them a bit loose, tightened them, and let the truck for the night.

Stoped by the house at Lunch today, my Bride tells me that the work I did last night has not cured the slow starting. In 10 minutes, I checked the voltage of the batteries connected together (12.83V), Checked them seperated from each other (12.83v Driver, 12.82v Passenger). Hooked it all back up, started the truck (still slow), measured the voltage at the batteries with the alternator charging (14.1v) I also did find the passenger battery was receiving 14.1v at the side terminal connections, but when I measured the voltage at the top posts, found 13.8v, engine running.

Did a search for ideas. Found check the ground attachments on the block (to be done in evening).

I have not load tested these batteries. Took another set to Auto Zone, and the tech said the battery voltage shoud be 12v (showed 12.3v unloaded). The load test took the batteries down to 11.22v. Tech declared them good. For 3 year old batteries, where should the static voltage and load voltages be to have some confidence ( ie: they are ok/good)?

Gotta work on this problem fast. Any ideas? Failing starter is not out of the realm.

TKS.

HammerWerf

[rameye]

Just because the voltages are good that really doesn't mean all is well...amperage is really what makes things go round...If your cables are crappy or you have marginal connections, you will get great voltages, but it wont turn over fast or at all.. Resistance in the cables or connections will cut your power right down regardless of battery health.

So it is most likely a marginal connection or cable...or a starter that is drawing way too much because its getting tired,,,drawing way too many amps.

Couple the symptoms with the fact that that your shop may well have beat the crap out of your starter purging the air from your system. These starter will heat up quick...once they get too hot, the covering s on the windings melt and they start to short. Not to mention your brushes may have gotten eaten during the process as well.

Dont rule out the fact that they may have cooked the main cable to the starter...seen that happen too!

my .02...

[DennisG01]

Stupid question, but, did you try charging the batteries?

[HammerWerf]

Dennis,
I measures the voltage at the battery terminals while the engine was running and got a reading of 14.1v at the terminal. One thing I did not check was to see if I had good contact at the terminal with the battery. I'll check that as I work on it.

Thanks for the idea.

HammerWerf

[DennisG01]

The reason I mention using an external charger on your batteries is if you haven't driven the truck for more than short periods of time since getting it back from the shop, then they may have never really re-charged well enough via the alternator. As mentioned above, the shop was probably doing a lot of cranking on it.

[DA BIG ONE]

Check the cells, or?

I have new batteries and have to top em w/distilled water say every 6 months or so. Another issue would be the + cable ends at pass side battery connecting both batteries it gets really messed up over time. I had removed my batteries and dipped cable terminal ends into baking soda/water mix to really clean em, steel brushed em then found I could not tighten them w/factory cable end bolts so upgraded to ss 9/16" bolts and washers. Check grounding straps too........................

Good luck

[Robyn]

Been through all this stuff with these little beasts.
The stock cables are notorious for corrosion under the rubber covers on the ends of the cables and under the crimped ends of the grounds even at the block.

The issue is usually cummulative and the core of the cables corrode to the point thatbn the outer strands of wire are all thats doing much and the amperage availability goes in the toilet.

Over time this loss can ruin the starter too.

I would replace all the cables with good new ones or make your own from welding cable and go to top terminal hookups with all soldered ends.

I did this on the 94 Burb and all the issues went away poof.

Also the lead from the Alt to the battery is to be suspect too.

You should see 14.1-14.7 volts at the first battery and maybe a couple tenths drop at the other (Running)

Do have a draw test done to be sure the batteries are not falling on their face with a load.
Best option is a set of Optima jello batteries. They dont need water and they dont leak and corode your truck.

If you decide to replace the starter (High miles? do it!!) dont use a parts store unit. Take yours to a good reputable auto electric shop that rebuilds them right there.
Less $$$ and far better quaility overall.

Good luck

Robyn

[HammerWerf]

Worked on the Suburban today to try and figure out what was happening.

Followed the ideas and leads provided herein.

Took Dennis's advise and swapped in a set of known to be good batteries. Fresh off a long drive in another truck. Thanks Dennis. Hadn't thought that a series of intown trips might not restore the charge, especially with the high temperature we were expirencing that week(lots of A/C).

I checked the battery connectors, and found that the passenger side battery negative connector was so corroded that it had been isolated from the circuit. No ground here. even the bolt had been isolated. Cleaned it up, then proceeded to check and clean up the others. Put it all back together, and she started right up.

New ground cables are in the que. the old ones don't have much life left in them. Think I try one of the tractor dealers who carry a really nice replacement cable that are somewhat see through.

Thanks for the guidance and assistance.

HammerWerf

[DennisG01]

If it helps:

I recently replaced all of my cables with larger, 1ga wire. I found pretty good prices at: www.wiringproducts.com

I used the top mount, soldered connections.

Glad to hear your problem was on the minor side of things!:D

[Robyn]

Good to hear that you vanquished the dragon. :);)

Robyn