All engine faults/repairs/maintenance reluctant starting Earths

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Primer for novices. The 12 volt electrical system uses wires to take current to the various devices on the vehicle like lights starter motor etc then uses the bodywork metal for the return circuit for the battery. This makes the final jump back to the battery with an earth 'strap' But along the way it may have other points where the earth circuit returns to the bodywork. these major earth ponts can be near the device being supplied usually with a brown or black wire (but not always!) The three original VW areas that you need to make sure are corrosion free are.

1. The 'Crown of Earths' this is on the nearside of the vehicle under the dash there are 2 circular metal earthing points with a number of male spade connectors poiting away from the body, a bit like a crown! these need cleaning the connectors to them need inspecting for corrosion.

2. The Gearbox nose Earth . This is usually quite corroded and if in doubt it is worth replacing so you know its been done.

3. Engine to bodywork earth strap


Hi all those of you that have read my thread/s re my non starting woes will know this, but am posting this in case it assists anyone in avoiding the 'start you "bar-steward"! If you don't start this time I swear, Im gonna get the matches.......' syndrome!!

So heres a list of issues I had

1) starter 'lag' when firing up from hot or cold. NOT the starter pinion oilite bush, but was the heavy wire from solenoid to starter breaking down, and eventuall fracturing completely. New starter motor fitted.

2) New starter worked for few days then ittermittent starting developed (but when she did start there was no longer any 'lag') Starter exchanged again (however, as you will see, that probably was NOT necessary!)

3) After postings on here, I also disconnected and cleaned up and refitted the two earthing straps. Things ok for couple days then, same problem.

4) Ignition switch all checked out ok. Solenoid exciter wire connection all good and tight.

5) Few days ago I replaced the two earth straps and bingo! Sorted

So, my tip is, and all credit to Mocki for his input, even though you have cleaned up those (probably original) copper earth straps untill they gleam, you have sanded the connection points back to bright metal, and you have used new nuts and bolts, you cant see the (presumably) corrosion INSIDE the crimped connections, nor the build up of resistance that comes with it. So, before you tear your hair out too, fit new earth straps.

As an aside, before all this happened, I had issues with battery not fully charging, and due to that the alternator was checked (output at battery) and found to be low. The connector at rear of alternator was in need of replacing back to brigh wire, and I also fitted a new regulator/brush pack.

This improved things but I still wasnt getting the results Ive seen posted on here... (I got 13.35v and unloaded tickover / 12.8 at loaded tickover)

Just had this rechecked since changing the earth straps, and now getting 14.1 at unloaded tickeover and 12.8 at loaded tickover)

Importantly though, Im getting a much better reading (13.35v) at 1500rpm loaded.

All in all, much happier