Thread: my 3.9i no start after hour in low range

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all wires to the starter / solenoid.

if you've got power, put the starter doesn't even turn, it's a power to the starter issue.

also check engine earth straps
b

Make sure your engine to chassis earth strap and the battery to engine earth strap are in good nick and properly grounded, Regards Frank.

You mentioned rain and mud in your post - I suspect the problem is actually your starter motor, specifically the high current solenoid. You don't mention the age of your Disco but if it's done more than 100,000 Km, and depending on how much water and mud it's been through in its past history, it's highly like that some more has just got into the starter solenoid. This can get between the contacts and prevent them from closing or it can cause the armature (the moving rod) in the solenoid to stick and the contacts never close. A tap with a hammer will usually fix this temporarily but the heat shield in the Disco is pretty good at stopping you getting anywhere near the solenoid to hit it (gently).

Alternatively, if there was a build-up of dust in there and a little water has got in today to turn it into mud (which won't readily displace when the contacts attempt to close) the effect is the same - no volts get to the high current windings in the starter motor itself.

If the solenoid is closing properly you'll hear a satisfying clunk and the dash lights will probably dim a little when you turn the key to "Start". I suspect that in your case, neither occurred.

The other possibility is that the carbon brushes in the starter motor are getting quite worn and you got just enough mud or moisture in there to prevent them making good contact with the copper segments on the rotating commutator. In this case, when you put the key into the "Start" position you'll hear the clunk but there'll be no significant current drawn and the dash lights will continue to glow nice and bright.

If I'm right, it's likely that the starter motor will continue to work OK for a few more weeks, failing occasionally, and then it will get worse until the starter motor is permanently dead.

You can do some checks with a multimeter when the car in in fault mode, but that rarely happens on your driveway when it's convenient to do so (Murphy's Law) and the clunk test is a good and simple starting point.

I think you should get emotionally prepared to pull out the starter motor though, to get it looked at. You'll need a 1/2" socket with an 8mm hex key fitted to it to undo the cap screws holding it into the bell housing. It's a bit tricky to get at the upper one and requires enough 1/2" extensions to get to the front of the engine. Do it when the exhaust pipe is cold and drop the header pipe from the manifold flange to give yourself enough room to manoeuvre the starter motor out.

Good luck.