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Model specific boards => Golf mk2 => Topic started by: paultownsend on 12 March 2008, 14:02

Title: rocker cover earth?
Post by: paultownsend on 12 March 2008, 14:02
im sorry but my cameras broken, so il try explain the best i can

there is a flat plastic covered lead that attatches to a thin plate on the rocker cover, and seems to dissappear to the area of the coil.
what is this for as during my bvh head it has snapped

Paul
Title: Re: rocker cover earth?
Post by: russ-vdub on 12 March 2008, 15:26
its only for protection really, not essential to have on .. dunno what you mean by "bvh head" tho?
Title: Re: rocker cover earth?
Post by: Diamond Hell on 12 March 2008, 15:35
Don't run the car without it - you can get odd earthing across the vehicle and it can pop the ECU.
Title: Re: rocker cover earth?
Post by: paultownsend on 12 March 2008, 15:35
oh sorry, big valve head!

excellent, so i can earth it anywhere really?
Title: Re: rocker cover earth?
Post by: russ-vdub on 12 March 2008, 16:36
earth is an earth at the end of the day.. just make sure you get a dvm and check that it is actually grounding
Title: Re: rocker cover earth?
Post by: Diamond Hell on 12 March 2008, 16:40
Quote
earth is an earth at the end of the day

No it's not.  If you don't earth the engine correctly you can get voltage differences across the body which will result in the ECU seeing wierd readings and possibly voltage above what the circuitry is designed to.  Then you get dead ECUs.

Earth it as it came out of the box and it'll work properly.
Title: Re: rocker cover earth?
Post by: russ-vdub on 12 March 2008, 16:45
where are voltages running through the rocker cover?? these are protective earths, thats all
Title: Re: rocker cover earth?
Post by: Diamond Hell on 12 March 2008, 16:48
It's earthing the engine to the shell.

Is it worth taking the risk of frying the ECU?
Title: Re: rocker cover earth?
Post by: russ-vdub on 12 March 2008, 16:55
agreed its not worth risking it but theoretically you can earth it anywhere on the chassis as all earths go to the chassis at the end of the day
Title: Re: rocker cover earth?
Post by: syncrogolf2 on 12 March 2008, 16:57
If you have a carburettor engine then this earth is not that important, but with a GTI digifant injection system this connection has an earth cable dedicated to the ECU and running about with this connected is just an accident waiting to happen, usually when starting up and the starter motor is pulling a lot of current & the usual earth cant keep up, then it can & will leave the ECU stone dead and unrepairable!

BTW this is not just a protective earth but actually part of the ECU injection & knock sensor circuit.
Title: Re: rocker cover earth?
Post by: russ-vdub on 12 March 2008, 16:59
hmm i know my rocker cover dont have an earth on it, hasnt had one since i owned the car. also my inlet is not earthed either for some unknown reason. right so if there are no earths wires floating around i have nothin to worry about? or do i?
Title: Re: rocker cover earth?
Post by: Diamond Hell on 12 March 2008, 17:02
Isn't yours a 16V motor? 

Possibly running K-Jet mechanical injection?
Title: Re: rocker cover earth?
Post by: russ-vdub on 12 March 2008, 17:09
nah digi 8v all the way
Title: Re: rocker cover earth?
Post by: paultownsend on 12 March 2008, 21:37
right, iv had the rocker powder coated, so shall i , where the earth is supposed to go, grind it down to bare metal?
Title: Re: rocker cover earth?
Post by: cняis on 12 March 2008, 23:20
hmm i know my rocker cover dont have an earth on it, hasnt had one since i owned the car. also my inlet is not earthed either for some unknown reason. right so if there are no earths wires floating around i have nothin to worry about? or do i?

my 90 spec 8v digi has no earth on the head.

my 89 8v digi project has a couple of earths on the head

go figure.

possibly only associate with older wiring systems (pre 90 with hazard switch on dash?)
Title: Re: rocker cover earth?
Post by: russ-vdub on 13 March 2008, 08:45
^^ hmm strange, i'll slap some earths on when i next re-dial my cam in :)
Title: Re: rocker cover earth?
Post by: cняis on 13 March 2008, 14:58
my '90 head has no holes to accept the earths though...

iirc the 89 project has 2 earths at the back right hand side (bolted onto the same earth point), and 1 earth to the front right hand side.

as i say im confident the daily has none of these, and no bolt holes to accept them either! perhaps it earthed elsewhere.
Title: Re: rocker cover earth?
Post by: Conker on 13 March 2008, 15:59
Isn't yours a 16V motor? 

Possibly running K-Jet mechanical injection?

My 16v K-Jet has a rocker cover earth as well.

Title: Re: rocker cover earth?
Post by: herbster on 13 March 2008, 19:01
My mate changed the rocker gasket before he gave me my 8v k-jet and it had fault every time I pit the lights on - the tacho died, this was the route of a lot of head scratching but eventualy after some forum guidance  :smiley: was down to the earth on the rocker not being fitted  :sad: soon cured once it was connected.  :wink:
Title: Re: rocker cover earth?
Post by: cняis on 13 March 2008, 21:11
funny my daily from memory doesnt appear to have one, and that has no electrical probs  :huh: