Jon W Posted June 16, 2017 Share Posted June 16, 2017 I have put an isolator switch on my series for ease of isolation and also to help with security. Due to lazyness and save having to crimp terminals on or solder etc. I have a correct length lead off a discovery with the following terminal on it. Can anyone tell me why I should use this. It is running all vehicle electrics, starter etc. If a winch was added it would have its own isolator on it Quote Link to comment Share on other sites More sharing options...
landroversforever Posted June 18, 2017 Share Posted June 18, 2017 That doesn't look like a very large cable to feed a starter?! Quote Link to comment Share on other sites More sharing options...
miketomcat Posted June 19, 2017 Share Posted June 19, 2017 He did say it's standard disco Ross. As to using the stud rather than the post, on Marine stuff we tend to use the studs as they are more positive than clamping a post. These days most clamps have a stud for the cable anyway so it's no different. Mike Quote Link to comment Share on other sites More sharing options...
landroversforever Posted June 19, 2017 Share Posted June 19, 2017 2 hours ago, miketomcat said: He did say it's standard disco Ross. As to using the stud rather than the post, on Marine stuff we tend to use the studs as they are more positive than clamping a post. These days most clamps have a stud for the cable anyway so it's no different. Mike Yeah, I'm just surprised its so small! Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted June 19, 2017 Share Posted June 19, 2017 Yep, normal size for RRC as well, but then I guess it has less distance to go than on a Defender. Studs are a great way to connect IMHO, only thing is you do lose a very small amount of surface area for clamping, but then... probably more reliable, so 6 of one, half dozen the other. I'd say go for it Quote Link to comment Share on other sites More sharing options...
Mo Murphy Posted June 19, 2017 Share Posted June 19, 2017 5 hours ago, landroversforever said: Yeah, I'm just surprised its so small! It's not small Ross, you just have big hands ? Mo Quote Link to comment Share on other sites More sharing options...
miketomcat Posted June 19, 2017 Share Posted June 19, 2017 Ask TSD what happens when you think the starter feed is to small and up it. I believe he literally blew two starters apart before he worked out land rover use that size cable to limit the current draw of the motor. Mike 1 Quote Link to comment Share on other sites More sharing options...
TSD Posted June 19, 2017 Share Posted June 19, 2017 It's true. If you give the tdi starter motor all the power it asks for, and then give it a sturdy load to turn (like my 2.8, or probably any tdi still making good compression) then the failure point is the epicyclic reduction gear carrier. (My starter is/was fed from twin parallel Optimas with probably no more than four feet of 25mm2 cable for both positive and ground.) (The Bosch Blue Book specifically mentions the wiring acting as current limit for starter motors.) First time (valeo motor) was driver abuse, winding Ibex + trailer + vehicle on trailer across a main road on the starter when the immobiliser failed (or rather, worked excessively well) Second time (Bosch motor) was out of the blue in a german service station, with no previous warning. Kept the engine running where possible for the next 1000 miles. Massive bonus points to Jansen LR independant in Holland, who sold me a starter motor at 6am on a Monday morning after they (like me) had driven all night from the Abenteur Allrad show in Germany, and then fitted it for me Quote Link to comment Share on other sites More sharing options...
steve b Posted June 19, 2017 Share Posted June 19, 2017 That's interesting Dave , learnt something on here again ...wandering off a bit , but not the same rules for electric winches ? cheers Steve b Quote Link to comment Share on other sites More sharing options...
TSD Posted June 19, 2017 Share Posted June 19, 2017 Same thinking, but different case I think. As I see it, it's the initial current and load torque combination. Losses are minimal when the motor is cold and not rotating, so max torque is available. For a starter motor there's no soft energy absorber (mud, drum tension etc.) to take out the shock load. Winch motor almost certainly is current limited by the wiring and the battery internal resistance, at the potentially higher currents drawn. But mostly, the starter motor has a tiny epicyclic with low ratio, where the winch has a huge one with high ratio. In both of my failures the carrier failed. In one, possibly both, the outer casing of the motor burst as the motor tried to force the gears round. I will try to find some pics later on. Quote Link to comment Share on other sites More sharing options...
TSD Posted June 19, 2017 Share Posted June 19, 2017 Few pics for interest. You can see there is a shock absorber in the outer gear ring...presumably not enough for the application though! 1 Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.