Page 2 of 2 FirstFirst 12
Results 21 to 38 of 38

Thread: 6.2 in an RV Low on Power

  1. #21
    Join Date
    Apr 2016
    Location
    Sarasota
    Posts
    129

    Default

    Determined that the low power issue was in fact the driver side rear brake was locked up due to a stuck parking brake actuator. While I was in there I rebuilt the rear brakes on both sides and bled new brake fluid.
    Now, when I try to crank the engine it won't turn over enough to start. Batteries are holding 12.35v, turn the key switch on it drops to 12.28v-12.3v, but turn it all the way to start and it drops below 4v. Up until just a few weeks ago when I started it last it cranked right up.
    Thoughts?

  2. #22
    Join Date
    Dec 2003
    Location
    Yukon Canada
    Posts
    1,290

    Default

    How old are the Batteries?
    Sometimes batteries will show a high surface charge,but as soon as you hit them with a load they drop voltage to basically nothing.
    I would load test them after being charged after 8 hours.
    Or a bad connection.
    90 Chev 3500 c/c 4x4,6.2na,400 auto,4:10 gears.DSG Timing gears,main girdle, isspro tach, pyro,boost,oil and trany temp.Dual Tstats, High volume peninsular pump,on shelf, Custom turbo and intercooler 85%complete. Change of plans for the dually, it's going to get a Cummins. Both trucks are Blue 90 4x4 crews

  3. #23
    Join Date
    Jan 2001
    Location
    New Hampshire - Live Free or Die
    Posts
    5,814

    Default

    12.35 Volts is not that good for lead acid batteries, about 60% charged. Closer to 12. 7 is better. Are you measuring the voltage at the batteries, or somewhere else? Two reasons batteries will drop that low. First is that at least one of the batteries is bad. The second is the starter is drawing 2 butt loads of current. This can be caused by a bad starter motor, or a seized engine.

    What happens if you turn the headlights on instead of the starter?
    The Constitution needs to be re-read, not re-written!

    If you can't handle Dr. Seuss, how will you handle real life?

    Current oil burners: MB GLK250 BlueTEC
    New ride: MB GLS450 - most stately
    Gone but not forgotten: '87 F350 7.3, '93 C2500 6.5, '95 K2500 6.5, '06 K2500HD 6.6, '90 MB 350SDL, Kubota 7510

  4. #24
    Join Date
    Apr 2016
    Location
    Sarasota
    Posts
    129

    Default

    Batteries are about 3 years old. I am measuring voltage on both batteries, right at the ends of the terminals. Original cables so it wouldn’t completely surprise me if the cables are at the end of their lifespan, either. Engine spins once or twice then barely chugs so it’s not locked up. It feels like too much resistance in the starter circuit, but it was getting dark and the dog needed to be walked so I couldn’t check on the connections at the starter, that’s my next area of interest.

  5. #25
    Join Date
    Jan 2001
    Location
    New Hampshire - Live Free or Die
    Posts
    5,814

    Default

    Put the voltage probes right on the edges of the lead pads coming out of the side of the battery and recheck.

    Are any of the connections getting hot?
    The Constitution needs to be re-read, not re-written!

    If you can't handle Dr. Seuss, how will you handle real life?

    Current oil burners: MB GLK250 BlueTEC
    New ride: MB GLS450 - most stately
    Gone but not forgotten: '87 F350 7.3, '93 C2500 6.5, '95 K2500 6.5, '06 K2500HD 6.6, '90 MB 350SDL, Kubota 7510

  6. #26
    Join Date
    Apr 2016
    Location
    Sarasota
    Posts
    129

    Default

    I've checked voltage at the posts and at the terminal pads on the upper battery (lower one is too hard to get to), same reading.
    Pulled the hot lead off the starter and cleaned it up, resistance across that wire back to the battery is near 0. I put it on the 2A charger to warm up overnight and will check again when I get home from work tomorrow. If I can get the batteries to hold 12.7v I pull the starter and have it tested.
    Dumb question, but I have the rear end sitting on stands, meaning the rear wheels aren't on the ground. Any chance there just isn't enough rubber touching the ground?

  7. #27
    Join Date
    Apr 2001
    Location
    CA
    Posts
    13,181

    Default

    Quote Originally Posted by Bigshankhank View Post
    ....Any chance there just isn't enough rubber touching the ground?
    Not a factor. You could have the entire chassis sitting on the ground, and it wouldn't make any difference. Sounds more like at least one failed battery, if you're seeing the voltage drop at the battery posts. A starter load enough to drop the voltage to 4V with healthy batteries would smoke the cables and/or connections in a few seconds. Continuous or repeated cranking with bad battery(ies) can damage the starter.
    1985 Blazer 6.2
    2001 GMC 2500HD D/A
    dmaxmaverick@thedieselpage.com

  8. #28
    Join Date
    Apr 2016
    Location
    Sarasota
    Posts
    129

    Default

    I wouldn’t have thought so but again, prior to putting it on stands to rebuild the rear brakes it was starting fine, now it’s not.
    I also noticed last night that, despite my voltmeter showing 12.3ish volts at the batteries, the dash voltage gauge isn’t showing anything, which it was working before. I had removed the gauge cluster last year to clean up contacts and see if the fuel & water temp gauge were faulty, and pretty much just plugged it back in just before working on the brakes two weekends ago.

  9. #29
    Join Date
    Apr 2001
    Location
    CA
    Posts
    13,181

    Default

    Causation vs. corelation. The engine cranked fine and started before, but not after jacking the rear end and messing with some electrical (corelation). Something changed (causation), but jacking the rear wasn't it. Messing with the IPC wasn't it. So, it must be something else.

    When you turn the key to Start, does the starter solenoid engage? Can you hear the starter hit the ring gear? Does it hit, then stop? Can you rotate the engine by hand (put a socket/breaker on the damper bolt, and "tighten" it)?
    1985 Blazer 6.2
    2001 GMC 2500HD D/A
    dmaxmaverick@thedieselpage.com

  10. #30
    Join Date
    Jan 2001
    Location
    New Hampshire - Live Free or Die
    Posts
    5,814

    Default

    Quote Originally Posted by Bigshankhank View Post
    despite my voltmeter showing 12.3ish volts at the batteries, the dash voltage gauge isn’t showing anything...
    You've got a couple of conflicting bits of information in the batteries drop to 4 volts on start attempt, and the dash gauge doesn't show any voltage ever.
    The Constitution needs to be re-read, not re-written!

    If you can't handle Dr. Seuss, how will you handle real life?

    Current oil burners: MB GLK250 BlueTEC
    New ride: MB GLS450 - most stately
    Gone but not forgotten: '87 F350 7.3, '93 C2500 6.5, '95 K2500 6.5, '06 K2500HD 6.6, '90 MB 350SDL, Kubota 7510

  11. #31
    Join Date
    Apr 2016
    Location
    Sarasota
    Posts
    129

    Default

    Quote Originally Posted by DmaxMaverick View Post
    Causation vs. corelation. The engine cranked fine and started before, but not after jacking the rear end and messing with some electrical (corelation). Something changed (causation), but jacking the rear wasn't it. Messing with the IPC wasn't it. So, it must be something else.

    When you turn the key to Start, does the starter solenoid engage? Can you hear the starter hit the ring gear? Does it hit, then stop? Can you rotate the engine by hand (put a socket/breaker on the damper bolt, and "tighten" it)?
    The starter spins the engine briefly, somewhere between 1/2 & a full rotation before the voltage drops off.
    Checked the charger off the batteries this evening, about 22 hours overall. Voltage reading was just a shade over 13v but I'll check it again in the morning to ensure I'm not reading a surface charge.

  12. #32
    Join Date
    Apr 2016
    Location
    Sarasota
    Posts
    129

    Default

    Quote Originally Posted by JohnC View Post
    You've got a couple of conflicting bits of information in the batteries drop to 4 volts on start attempt, and the dash gauge doesn't show any voltage ever.
    How do you mean? My voltmeter shows voltage, the gauge on the dash doesn't. For some reason voltage is no longer making it to the gauge when it was working fine before. That being said, other gauges still function and the dash lights still work so its not a matter of no power is getting to cluster.

  13. #33
    Join Date
    Jan 2001
    Location
    New Hampshire - Live Free or Die
    Posts
    5,814

    Default

    All I'm saying is that if the voltage gauge isn't showing voltage, what else may not be seeing voltage as well? That said, if it cranks briefly, then grinds to a halt, sure sounds like bad batteries to me. Put the headlights on for a few seconds to draw off any surface charge. If I were you, I'd take the batteries to a parts store that can test them for you. Charge them first, individually (remove the ground from at least one to isolate them) and test them individually. One bad battery can quickly kill the other.
    The Constitution needs to be re-read, not re-written!

    If you can't handle Dr. Seuss, how will you handle real life?

    Current oil burners: MB GLK250 BlueTEC
    New ride: MB GLS450 - most stately
    Gone but not forgotten: '87 F350 7.3, '93 C2500 6.5, '95 K2500 6.5, '06 K2500HD 6.6, '90 MB 350SDL, Kubota 7510

  14. #34
    Join Date
    Apr 2001
    Location
    Newberg Oregon
    Posts
    11,493

    Default

    Any more....a 3 year old battery is suspect.
    I jumped in our Avalanche a few weeks ago....Fired right up...drove to town, came home... next morning deader than a post......

    Battery was bought new 28 months ago....

    Dropped in a fresh battery. all good to go...

    Batteries do not last like they did a few years ago...The Red Top Optima Glass mat batteries used to go 6 years easy and many times 8 or more....Not now... Get 3 years and ya better be watching your 6......

    I would suspect the batteries.....Charge them up and get a draw test done on each one.....

    If one is bad....replace both...
    (1) 1995 Suburban 2500 4x4
    (1) 1997 Astro
    (1) 2007 Chevy Avalanche
    THIS IS BOW TIE COUNTRY

  15. #35
    Join Date
    Apr 2016
    Location
    Sarasota
    Posts
    129

    Default

    Was super busy this weekend and a day slipped by me without me noticing.
    Saturday morning the batteries were still holding 12.65v so I tripled checked my main engine grounds (major pain considering one is beneath the doghouse) and the one of the driver side accessory bracket was a little loose so I cranked down on that one a tad, hopped up in the cab and it fired up. Actually it was spying fine but took a little bit to catch due to the relative cold weather, as luck would have it the PO had put a momentary switch on the GPs so once I warmed them up it fired up.
    FWIW I have only driven this rig twice previously as we bought it in non-running condition. First time was right after replacing the broken alternator bracket but it was leaking fuel & coolant so it was just up the street and back, the 2nd time (after fixing the leaks) was around the block till I noticed the brakes dragging. Now that I have the brakes sorted I was actually bold enough to take this up on the local highway and open it up. Its not fast, took every bit of a 1/4 mile to get to 50mph at which point I had reached the other entrance to our neighborhood and started slowing. But the engine was still pulling when I hit the brakes so all in all it was good exercise for it. Thanks for all of the help in this thread. I'm sure the batteries will need replacement as will the tires (nearing 5 years old) before too much longer but for the time being its be fine for local trips to the state park about 30 miles from here.

  16. #36
    Join Date
    Apr 2001
    Location
    CA
    Posts
    13,181

    Default

    That's great. Always a wiseguy in the works. Notice the long conversation about something so stupid-simple. Happens to all of us, from time to time.
    1985 Blazer 6.2
    2001 GMC 2500HD D/A
    dmaxmaverick@thedieselpage.com

  17. #37
    Join Date
    Apr 2016
    Location
    Sarasota
    Posts
    129

    Default

    Quote Originally Posted by DmaxMaverick View Post
    That's great. Always a wiseguy in the works. Notice the long conversation about something so stupid-simple. Happens to all of us, from time to time.
    Well there’s nothing worse than someone starting a “Help Me” thread and then not closing the loop as to how/if the problem got solved.
    Honestly I think I would enjoy working on this thing more if it wasn’t in a van, that makes everything such a chore.

  18. #38
    Join Date
    Apr 2001
    Location
    Newberg Oregon
    Posts
    11,493

    Default

    Vans have some great points.....But working on them is NOT one of them....

    Glad you got things sorted out....
    (1) 1995 Suburban 2500 4x4
    (1) 1997 Astro
    (1) 2007 Chevy Avalanche
    THIS IS BOW TIE COUNTRY

Similar Threads

  1. 83 GMC 4X4 power steering and power brakes issuse
    By TRASH_PANDA in forum 6.2L Diesel - Tech Support - Troubleshooting - Performance
    Replies: 1
    Last Post: 05-05-2019, 20:54
  2. loss of tack,power stearing and power brakes
    By N9Phil in forum 6.5L Turbo Diesel - Tech Support - Troubleshooting - Performance
    Replies: 5
    Last Post: 09-08-2015, 20:10
  3. Adding Power Heated Mirrors to Non-Power Mirror Truck - Wiring?
    By campionc in forum 6.5L Turbo Diesel - Tech Support - Troubleshooting - Performance
    Replies: 4
    Last Post: 04-18-2015, 10:35
  4. loss of power steering and power brakes
    By 3ace in forum 6.2L Diesel - Tech Support - Troubleshooting - Performance
    Replies: 2
    Last Post: 06-16-2014, 13:05
  5. Power steering and power breaks occasionally temporarily go out.
    By jfile in forum 2500HD/3500 HD Trucks & Drivetrain
    Replies: 5
    Last Post: 01-13-2005, 16:14

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •