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Securing Wiring- spacing
James - 26/5/05 at 06:50 PM

Can't find anywhere in my SVA manual that talks about the spacing of the 'P'clips/zip ties etc. that secure the wiring.

I've done my brakes and fuel line at 150mm so I'm doing the same for the wiring. Anyone got any reasons to change this? (like the page number in the manual that says what it should be! )

Thanks,
James


Deckman001 - 26/5/05 at 07:53 PM

AFAIK they are the same distance apart, i think it's less than 300mm so 150 centres are fine
Jason


wilkingj - 26/5/05 at 08:27 PM

Section 15.2 says:
Secured at intervals of not less than 300mm unless in a hollow component.

Checks are for:
Security
Insulation
Positioning
Capacity

Fail points:
adhesive tape or pads are a no no.
dont run with the fuel lines.
not near the exhaust ( Insulation damage - heat problems)
no Chafing.
Too thin wires ie inadequate for the loading.
no bare wires (short circuit hazard)
not subject to corrosive environment.
Not securely clipped to the vehicle


Personally I would stick to 150mm like you say. ie well fixed.


DarrenW - 27/5/05 at 10:18 AM

quote:
Originally posted by wilkingj
Section 15.2 says:
Secured at intervals of not less than 300mm unless in a hollow component.





No more than 300mm is the rule iirc, ie make them less than 300 apart. My father also fell foul of having some runs not supported by chassis etc - ie he cut across an open space even the the clips were less than 300. Something to do with if road debris etc entered that area it could damage the loom.


James - 27/5/05 at 10:30 AM

Ok, sounds like mine's fine then as I'll pass on all the points that are mentioned.

I've used sticky pads but they're riveted aswell so should be ok (and I'm willing to cut the zips to prove the rivets exist!) hopefully.

My front, rear and engine looms are all sleeved in PVC(?) tubing. The centre/instrument loom is not sleeved. I presume it's ok to use zip ties against the wires themselves? There's no sensible way I could sleeve the middle loom as it's too complex. Or should I wrap the centre loom in PVC tape where it's held by the zip?

Cheers,
James


DarrenW - 27/5/05 at 10:39 AM

Rivetting the adhesive bases on is OK.

Im sure the rule of thumb is that if an OEM does it then its OK for SVA. i think the inspectors like to see a factory or better finish. Car looms tend to be wrapped under the dash and secured with ties. Ive seen se7ens pass with the wires tied to the chassis etc. A bit of tape wont go a miss as itll prevent chaffing with the vibration. Can you fit spirwrap or is the loom too thick at that point.
I think id take a chance with tape. Stops it looking like a rats nest. Im sure you will make it secure.

A tip not directly related is that if there are any areas not easily visible by the inspector, take some pics just in case he wants to see. This might be usefull for under dash area and clips in the tranny tunnel. (Dad had to go back with tunnel easily removeable for inspection at Gosforth near Newcastle).

[Edited on 27/5/05 by DarrenW]


James - 27/5/05 at 10:52 AM

quote:
Originally posted by DarrenW
Car looms tend to be wrapped under the dash and secured with ties. Ive seen se7ens pass with the wires tied to the chassis etc. A bit of tape wont go a miss as itll prevent chaffing with the vibration. Can you fit spirwrap or is the loom too thick at that point.

[Edited on 27/5/05 by DarrenW]


Fair point. Only a five minute job with PVC.

There's too much stuff coming of it to fit spira wrap but PVC will be fine. It's not too rat nsst like as it's a Premier Wiring jobby so pretty neat anyway.

Is it me or are there two types of PVC wrap? Sticky and not sticky? Or is it just that the old stuff I've cut off the Sierra goes sticky with age?

Cheers,
James


DarrenW - 27/5/05 at 11:01 AM

There are different types of insulating tape. Some are more stretchy. Ihave heard of proper wiring tape. Hopefully someone can explain and advise source. ive always used insulating tape to wrap hi-fi looms on my old cars but ive heard of people having SVA problems. I think this is more when it i sused in external areas where the environment can effect its performance and leave wires to come loose. It may be oK in a protected area like under dash, especially as you will only use it to hold the wiring together for neatness then use planty of cable ties to secure it. Even if the tape started to lose stick the ties woiuld hold it in place - it adds another mechanical barrier.

im sure ive seen OEM looms wrapped and then covered with a foam sleeve - not sure what that is for. Might be worth taking a look at the breakers (photos as well for the SVA discussion??)


Bob C - 27/5/05 at 11:28 AM

I've seen the foam too, I reckon it's to stop rattling/buzzing
Bob


NS Dev - 27/5/05 at 12:18 PM

quote:
Originally posted by DarrenW
There are different types of insulating tape. Some are more stretchy. Ihave heard of proper wiring tape. Hopefully someone can explain and advise source. ive always used insulating tape to wrap hi-fi looms on my old cars but ive heard of people having SVA problems. I think this is more when it i sused in external areas where the environment can effect its performance and leave wires to come loose. It may be oK in a protected area like under dash, especially as you will only use it to hold the wiring together for neatness then use planty of cable ties to secure it. Even if the tape started to lose stick the ties woiuld hold it in place - it adds another mechanical barrier.

im sure ive seen OEM looms wrapped and then covered with a foam sleeve - not sure what that is for. Might be worth taking a look at the breakers (photos as well for the SVA discussion??)


Couple of answers for you Darren,

non-sticky loom tape can be had from vehicle wiring products, VWP, sleeving and tapes

and yes, a lot of manufacturers use a foam wrap over the loom tape, particularly in the dash area.

The three cars that I have recently dismantled, a sierra, Astra GTE 16v and Cavalier SRI, all had this foam cladding on parts of the loom.

It is very much like small diameter pipe insulation, but sticky inside to hold it on.