1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

2LT cranks slower and slower...

Discussion in 'Diesel Tech / 24 volts' started by Previa Diesel, May 10, 2018.

  1. Previa Diesel

    Previa Diesel

    Messages:
    343
    Likes Received:
    1
    Joined:
    May 23, 2004
    Location:
    South Island
    ...and now doesn't crank at all.

    After 5-7 seconds the starter would pick up speed and she would fire, but gradually this period got longer and longer until it stopped picking up speed and just got slower.

    Cleaned up and charged the batteries, cleaned the contacts on the leads, replaced the terminals and of course cleaned up the posts on the batteries, put it all back together and nothing, not a click, not even a light. Batteries are both showing almost 13v. Tried a spare starter relay, checked the fuses and fuseable links...I'm mystified.

    Next is to check the contacts in the starter; brushes have been suggested as a possible problem, but I know the 2LTs tend to burn up their starter contacts...

    But that doesn't explain the complete lack of power to the system now.

    Anyone care to speculate?
     
  2. CreeperSleeper

    CreeperSleeper SILVER Star

    Messages:
    6,643
    Likes Received:
    527
    Joined:
    May 16, 2005
    Location:
    Forest Grove, OR
    Check voltage at the starter terminal. You may have a loss in the wire itself. My only other thought would be the contacts in the starter itself (which you already mentioned).
     
  3. roscoFJ73

    roscoFJ73

    Messages:
    15,182
    Media:
    3
    Albums:
    1
    Likes Received:
    1,466
    Joined:
    Jul 22, 2003
    Location:
    Perth Western Australia
    You need to get your batteries load tested or buy a gadget and do it yourself. Or if you can get someone to crank it while you hold a multimeter on the battery and on the starter terminal as creepy suggested. .
    What the voltage shows when there in no load on the battery means nothing. My guess is that your battery is diving to 8-9 vols under load. I think they should stay around 10-11 minimum

    NO power at all means you probably blew a fusible link. They are connected close to the positive terminal.
    You can either make your own by buying a suitable piece of fuse wire or buy them premade.
    They look something like this. [​IMG]


    Another place to check is where the earth strap is connected to the engine, make sure its not corroded.
     
    Last edited: May 13, 2018
    GTSSportCoupe likes this.
  4. Tugarin

    Tugarin

    Messages:
    227
    Likes Received:
    123
    Joined:
    Jan 11, 2011
    I would get a two pieces of decent cable and from and crank the engine directly. It will show you if you have problem in the cabling, battery or starter.
     
  5. Previa Diesel

    Previa Diesel

    Messages:
    343
    Likes Received:
    1
    Joined:
    May 23, 2004
    Location:
    South Island
    I appreciate the suggestions and I'll follow up on those. More likely to be something like the links probably as I get no power at all when the key is turned; nothing. I've been all over this thing with the FSM and a multi-meter, checked everything I can find from the ground cables to the continuity of the ignition switch. Swapped the starter for a good spare, but it may have been wasted effort.
     
    Last edited: May 17, 2018 at 11:25 AM
  6. BreckenridgeCruiser

    BreckenridgeCruiser I break things. SILVER Star

    Messages:
    2,586
    Likes Received:
    110
    Joined:
    Aug 14, 2006
    Location:
    Now in Sunny Encinitas, CA!!
    Check the ground from the starter to the frame... Mine did the same thing and everything g else ewas good... Replaced that ground cable and everything worked again like there was never a problem. The other suggestions are good, but I just noticed that you didn't mention this cable....
     
  7. Previa Diesel

    Previa Diesel

    Messages:
    343
    Likes Received:
    1
    Joined:
    May 23, 2004
    Location:
    South Island
    Thanks BreckenridgeCruisier, Got my batteries tested this am for load and found one was good and one was very weak. Eight years old so got a couple of decent used ones to replace. Dropped them and still nothing, not even lights. FSM shows two wires to starter: the lead direct from the battery and the one with the green connector. Both are cleaned and in place and the battery lead tested for continuity, though not yet for voltage at the battery.

    So is the smaller wire with the green connector the "ground from the starter to the frame" or am I missing something? The two I mentioned are the only ones that were there before. Perhaps I've blown the wire with the green connector somewhere? Will have to trace it out I guess.

    This is a 12V dual battery system as you know.

    RoscoFJ73, I traced the cables, but no fuseable links found outside the fuse box and those all look OK and test for continuity. I've tested the starter relay as per the FSM.
     
    Last edited: May 17, 2018 at 4:03 PM
  8. roscoFJ73

    roscoFJ73

    Messages:
    15,182
    Media:
    3
    Albums:
    1
    Likes Received:
    1,466
    Joined:
    Jul 22, 2003
    Location:
    Perth Western Australia
    Previa is similar to a Toyota Tarago, Estima? I just asked my son ,he works in a spare parts store that does a lot of Toyota stuff He says there should be a fusible link near the positIve terminal, but it will be the square plastic type , not the Landcruiser type that posted a pic of.
    What year is your Previa?
    I often wondered about buying a Tarago etc, I know most people who owned them love them.

    upload_2018-5-18_7-34-41.jpeg
     
  9. Previa Diesel

    Previa Diesel

    Messages:
    343
    Likes Received:
    1
    Joined:
    May 23, 2004
    Location:
    South Island
    This is an 87 2LT diesel pickup, NA market BTW.

    So after another afternoon fiddling around I am 90% sure I have the problem nailed: worn out ignition switch. I went back to that again with the multimeter and using my third hand proved to myself that I wasn't doing it correctly the first time. Continuity was NOT as per the FSM. Pulled the switch, pulled it apart and sure enough, the brass(?) contact ring and the corresponding brass(?) studs were severely worn. The ring was worn from .033" down to about .026" around along the travel of the contact and as little as .014" where the actual stud contacts the ring in the "START" position. No sign of arcing, which surprises me a little, but that may not be significant.

    I guess the gradual increase in cranking speed was caused by the arc across the wear gap gradually gaining strength.

    So, one used switch coming up, I hope.

    Thanks for the help!
     
    Last edited: May 17, 2018 at 8:58 PM
  10. Previa Diesel

    Previa Diesel

    Messages:
    343
    Likes Received:
    1
    Joined:
    May 23, 2004
    Location:
    South Island
    Can't see any edit option when using my phone, so will add photos here. The first photo is after all the metal dust was brushed off, which you can see in the third photo.

    IMG_20180517_181801_edit.jpg

    IMG_20180517_180709_edit.jpg

    IMG_20180517_180310_edit.jpg

    IMG_20180517_180522_edit.jpg