R300 wiring help?
Discussion
Hi all,
Me my brother and father are in the finishing stages of building a R300 and have hit a snag with how the wiring is all connected between the battery, alternator, starter and earth.
At the moment we have;
red +ive lead from battery to starter motor (on the terminal furthest from the block).
black lead in black sleeving from starter (same terminal as red +ive) to alternator.
Black lead from bell housing to battery -ive.
2 brown wires with eyelets (at the rear of engine bay) connected to earth.
2 red and white wires connected to starter via the middle terminal.
1 spare black lead currently no connected to anything?
With the wires like this nothing works so something must be wrong somewhere, if anyone could guide us in the right direction or even post a pic of their wiring it would be most appreciated.
Many Thanks, Tom
Me my brother and father are in the finishing stages of building a R300 and have hit a snag with how the wiring is all connected between the battery, alternator, starter and earth.
At the moment we have;
red +ive lead from battery to starter motor (on the terminal furthest from the block).
black lead in black sleeving from starter (same terminal as red +ive) to alternator.
Black lead from bell housing to battery -ive.
2 brown wires with eyelets (at the rear of engine bay) connected to earth.
2 red and white wires connected to starter via the middle terminal.
1 spare black lead currently no connected to anything?
With the wires like this nothing works so something must be wrong somewhere, if anyone could guide us in the right direction or even post a pic of their wiring it would be most appreciated.
Many Thanks, Tom
Hi Tom,
May not be able to help much but also very intertested in any other replies. At exactly this stage with my Roadsport 175 SV so fairly similar.
I think I have done exactly what you have and have at least got a peep out of the horn with battery connected and the ignition switch to first click. Have not tried cranking it yet.
Photo shows the back of my starter motor at moment.

I also have nothing on the back terminal yet.
I also have a 300mm long cable from the LHS engine chassis mount that is not connected to anywhere yet.
Assembly guide is pretty hopeless once you get to electrics & plumbing IMHO.
Interested to see what anyone else comes up with.
Chris
May not be able to help much but also very intertested in any other replies. At exactly this stage with my Roadsport 175 SV so fairly similar.
I think I have done exactly what you have and have at least got a peep out of the horn with battery connected and the ignition switch to first click. Have not tried cranking it yet.
Photo shows the back of my starter motor at moment.
I also have nothing on the back terminal yet.
I also have a 300mm long cable from the LHS engine chassis mount that is not connected to anywhere yet.
Assembly guide is pretty hopeless once you get to electrics & plumbing IMHO.
Interested to see what anyone else comes up with.
Chris
Stuart,
Thanks for the warning about NOT earthing the rear terminal of the starter motor ... will take that on board!.
Sounds like I need to take the 300mm lead from the LHS engine mount/chassis to somewhere solid on the engine ... even a bolt at the engine end of the engine mount bracket.
Thanks again for the advice.
Chris
Thanks for the warning about NOT earthing the rear terminal of the starter motor ... will take that on board!.
Sounds like I need to take the 300mm lead from the LHS engine mount/chassis to somewhere solid on the engine ... even a bolt at the engine end of the engine mount bracket.
Thanks again for the advice.
Chris
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