Connecting the battery question - 420R build

[Ainsley]

I'm struggling with the 3 battery connecting wires I have.

The short black one is now under an engine mount and earthed to the block, so that should be good.

But the long black one I assume goes from the -ve terminal on the battery to what ?  The bolt hole on top of the LH footwell seems obvious, but why is the cable so long ?

On some blogs I've seen it bolted to the RH side of the bellhousing, just underneath the exhaust.  Which obviously requires the lead to be long, but why there under a hot exhaust ?

Where does the +ve one go - the starter motor I assume, but which terminal on the starter motor ?

Also, can anyone recommend some nice connectors to the battery, rather than bolt them on and risk losing those flimsy plastic covers currently on the battery.

[SM25T]

+ve goes to the terminal on the starter motor that is switched by the solenoid to operate the starter. otherwise it would be running the whole time ! Same terminal connects onwards to the alternator output terminal.

[Jonathan Kay]

6 minutes ago, Ainsley said:

Where does the +ve one go - the starter motor I assume, but which terminal on the starter motor ?

But if there's any doubt please post a photo of the terminals on the starter and any identification.

Jonathan

[Ainsley]

Ah, that looks clear.  Not sure why I didn't look at that page on the manual.

Any suggestions as to the battery end of the connectors as opposed to bolts ?

[Jonathan Kay]

4 minutes ago, Ainsley said:

Any suggestions as to the battery end of the connectors as opposed to bolts ?

Please add a photo of the wires near the battery posts.

Jonathan

PS: There's a recent thread about covers for connections on Banner batteries:

[Peter_V]

For my ongoing 420 sv build I had the same thoughts about the -ve wires from the battery.

However, I read on the tiggercaterham.co.uk blog that during the PBC Caterham moved the -ve  wire away from the hot exhaust on the RHS to the starter motor retaining bolt on the engine LHS. I've done this with the long wire and it looks quite tidy.  This has left me with a short -ve lead from the battery to the chassis earth point next to the battery as page 95 of the guide. 

I therfore don't have a chassis earth connection under the LHS engine mount even though they still supply one longer bolt for this in the kit. I presume this requirement  has been superseded by the earth point next to the battery.

Happy to be corrected here. 

 

[Ainsley]

Yeah, I feel two short -ve leads would be fine.

One from the LH engine mount to the block, one from the battery to the LH footwell.  No need to go near the hot exhausts.

I've been looking at lots of blogs, which are very helpful.  Apart from one where they had fitted the driver seat runners the wrong way round.  So I too followed the picture and fitted mine the wrong way round.  Next week my mate in the village picks up his 420R, so I shall be all over it looking to see what goes where and how.  

[lapsedtheorist]

One thing to bear in mind is that Caterham will shorten cables for you if you ask them as part of PBC. I had a particularly long +ve cable from the battery and they took a big chunk out of the length which was really helpful.

[Graham Hutton]

5 hours ago, Ainsley said:

Yeah, I feel two short -ve leads would be fine.

One from the LH engine mount to the block, one from the battery to the LH footwell.  No need to go near the hot exhausts.

I've been looking at lots of blogs, which are very helpful.  Apart from one where they had fitted the driver seat runners the wrong way round.  So I too followed the picture and fitted mine the wrong way round.  Next week my mate in the village picks up his 420R, so I shall be all over it looking to see what goes where and how.  

My 310R kit had that exact cable arrangement and it worked brilliantly. It was just the +ve cable that was a bit too long and I kind of cable clipped it to the loom to keep it tidy. I did take a picture off the internet from a blog showing the cable connectors to the started motor to make sure I din't completely cock it up and I'm delighted that I didn't.......on that occasion 🙂

[Ainsley]

OK, Im still confused.  

Looking at the wiring diagram Johnathan posted above, there are only two points for the wires to go onto.

Whereas in my case there are 3.

As per the diagram:

#5 Red/White is connected fine.

#2 brown with black sheath is connected fine.

Leaving #4 and #3.

If I put these both on the same terminal (bottom right in the picture) then there is no space left for the nut to screw on.

In the picture there are clearly 3 terminals, but in the diagram only 2.

So, where does the red +ve lead go and where does the 2 brown ring ending cables go ?

Confused 😞

[SM25T]

I would say they all go on the terminal without the nut fitted at the moment.

[Graham Hutton]

Here is a picture of mine albeit on a sigma 310R engine. I think the starter motor is the same though.IMG_3768.HEICIMG_3768.HEIC

[Graham Hutton]

Here it is!

IMG_3768.HEIC

[Ainsley]

I did try that, but the thread was not long enough for all of them plus the shake proof washer as well 😞

If you look closely at my picture, the first few mill of the thread are actually smaller than the final section.

Did you mange to squeeze them all plus a washer on that thread ?

[lapsedtheorist]

I had the same issue with my build, just take off the shakeproof washer and do it up. For peace of mind, I actually switched nuts to a thin nyloc, which seems to be fine. Here’s a close-up from my build, which is the image I sent to Caterham for clarification on what to do.

[Ainsley]

OK, will do.  

Thanks.

[Geoff Brown]

Nothing has changed to do with wiring up then ? Back in the mists of time - 2012 - I came up against the same thing but then the Build Manual was a total waste of space concerning routing & connections.

As mentioned above there was not enough terminal post length for all the cables unless a thin standard nut & shakeproof washer was utilised.

Edited March 21 by Geoff Brown

[Ainsley]

Thin nut is being ordered as we speak 🙂

[ScottR400D]

“The short black one is now under an engine mount and earthed to the block, so that should be good.“

You haven’t scraped off the PC and put one of the ground leads to the chassis at the engine mount have you? 
Back In 2015 I was reluctant to damage the PC that way and asked why I couldn’t connect the lead to the spare M8 rivnut to the left of the battery. CC had no good reason for not doing that so I did and it’s been fine. 

[Ainsley]

Yup, I scraped off the PC !

Basically so did a lot of the blog creators I looked at online 🙂

I will be painting over it with a thick layer of Hammarite, and being a fairy and driving it in dry weather however.

[ScottR400D]

Is that what the manual said? I thought they’d stopped recommending that destructive method. 

[Ainsley]

It doesn't show the earth strap going to the engine mount / block.  But quite a few blogs do.

Certainly no diagram / picture of where to connect what to the starter motor.

[ScottR400D]

That diagram shows the earth strap going to the M8 rivnut. To be honest I thought they’d changed it after I discussed the possibility in 2015. One lead to the bell housing, one to the rivnut. Back in 2015 I had to make up a short lead to replace the long one supplied but I thought they’d supply a short one now. 

Connecting to the engine mount was the old way. 

[Ainsley]

I got two -ve leads, one long, one short and one long +ve lead.

So basically I've done it the old way - as per a few blogs.  I should have just read the instructions before looking at the build blogs.  It was one of the engine install blogs that showed the earth lead from the mount to the engine that got me going on that route.

This weekend I will undo that and do it as per the diagram 🙂

[ScottR400D]

For years CC recommended the remove PC and fix to engine mount. Lots of builders will have done that. I’m sure it works and no one gets serious corrosion there but it went against the grain for me to deliberately damage the PC.