'97 Disco 1

I've been chasing an issue with not enough power to adequately crank the starter. Many $'s expended replacing battery, starter (nice new British Starters unit), new reman Bosch alternator,.... The net is it still starts like the battery is almost dead, even it's fully charged and bypassing the kicker board starter relay. Usually it will eventually start after what sounds like rrr.rrr....click..click....rrrr...click..click rrr.

Any troubleshooting suggestions appreciated.

No winch or other big added loads, no wiring mods.

Thanks

 

Have you checked and cleaned the GROUNDS... Negative Battery Cable to Frame and Starter to Frame?

 

Yes, battery ground sanded, dielectric applied, and electrically checked.

One more big clue in last few minutes, when jumping starter relay I could hear something that sounded like a short (arcing), now no power to anything. No blown fuses, and voltage is present at engine compartment fuse box. Something has blown or burned out that feeds everything downstream of the engine compartment fuse box. Suspecting combo of new alternator power, and my jumping starter relay, probably finally burned it out. But I have no idea what "that" fuse/relay or wire is.

 

Don't rule out a bad from stock starter. Several other members have had similar issues resolved by another starter.
......

 

Check grounds for sure, also check voltage at starter with a meter, it may be possible to have corrosion or loose cables, also check starter relay in right side kick panel


Try swapping out relay with an extra relay to see if there is any change. You can check for +12 volt power at pin 30 with key in the off position and check for +12 volt power on pin 87 when the key is in the start (Crank) position.



This is the diagram for the relay in the kick panel you should have 12 volts on pin 30 and 12 volts at pin 87 when the key is in the start position.



You should have 12 volts at pin 30 and 12 volts on pin 1 when the key is in the start position.

 

 

Thanks all. Invaluable info and diagrams, all recommendations executed.

< 1 ohm resistance between (-) battery terminal and random point on frame rail, so grounding checks good.

Where I was an hour ago: no electrical power to driver's side fuse box, nothing electrical powered, no jumpering of starter, no hazard light, no power anywhere.

What I did: pulled that driver side “fascia” fuse box (main, satellite 1 &2) out, stared at it. Hooked up battery again, put key back in, power now miraculously back on, starter cranks strong, unlike before.

What I think: I didn’t need a new alternator or starter, but at 230K miles ok with swapping them out. Something shorted out in the harness related to the fuse box, moving fusebox cleared it, moving it/vibs will also bring it back,... so I need to isolate it, LOL.

Thanks again for the help, any recommendations on fusebox wiring issues appreciated. (or whatever else this might be)

 

I wouldn't think a bad fuse would cause the click click like a dead battery. but if it works. go for it!!

 

I wanted to wrap this in up in case others find the same problem and easily overlook, or are misled from, what the solution is.

Symptom: Starter cranks but dies out as it cranking, as if the battery is dead, though it is charged. Sometimes it would recover and get to idle, other times I’d get “click, click” of the starter relay.

Troubleshooting:

- I performed all the usually electrical checks, notably checked resistance between starter case and ground point for battery (on chassis rail RHS of engine compartment). That always checked good, < .5 ohms.
- With a ’97 LR1 with 230K, and original starter, I simply figured it was time for a new starter, installed a new British Starters unit. While it clearly performed better, the mid-crank die out persisted. Since everything was old I tried isolation by r&r’ing remaining relevant components one at time: starter relay, alternator, and battery as well.
- Though it cranked fast, and the lights were bright than ever, it frustratingly had the same starter die out symptom.
- I tore apart the electrical power distribution systems hunting for something anomalous that would explain why voltage or the ground was going away in the middle of start. (the RAVE electrical pub was invaluable)

Root Cause:

Replacing the starter is easy, I didn’t bother to read the instructions other than getting the mounting bolt toque values. *** I didn’t know there was a ground bond strap between the upper starter mounting bolt and the frame. *** I had assumed it just grounded itself through the transmission bell housing and some other engine strap took the whole engine back to ground. And I had cleaned the primary engine battery ground. The problem was that during the start that ground path via the bell housing was unreliable, effectively increasing ground resistance due to mechanical contact being lost, or oil, dirt, etc during the crank. As the ground resistance increased due to these factors the starter lost its ability crank mid way though start cycle and would die out.

Final fix: I looked above the starter and there tucked away was a ground strap that had not been connected in over decade. I cleaned it and its mount points, then measured 0.2 ohms to the battery frame ground point. I cranked it, closed my eyes, and for a brief second the awesomely powerful wrrrrrr of my new geared starter sounded like a McLaren. Many starts later it remains so, the mid crank die out is gone.

I now want a geared started for all my vehicles, …. and a good ground bond strap.

 

Glad you got it sorted!
And I'm NOT giving you over it, but next time slow down and read the responses to your post....
...you could have had this fixed 10 days ago.