ABF oil light flashing - steel sump not suitable for ABF pickup

[fishnchipsx2]

Helloo,

I have a consistently flashing oil light on my mk1 ABF conversion.  Engine is a high-miler. Didn't get to see it running before.  Tappety, but nothing outrageous.

Done a few hundred miles with it like this, cos I assumed I had wired the pressure switches the wrong way round.    Finally got round to getting a closer look at it today, and my wiring seems to be good:

Blue/black wire to brown switch closer to block, and yellow wire to white switch closer to rad on the right.

Tried a different set of clocks, light still flashes.

Flushed the oil, and while it was empty, whipped off my steel sump to get a look at the pickup. (Swapped alloy sump for steel when I did conversion.) Pickup is clear, but there were marks on the steel sump where it had been fouling the bottom 



(The 4 big marks are where paint has burnt off from welding the sump guard on.)

The marks to the RHS of the pickup hollow are where the ABF pickup has been fouling, due to it's differently shaped shroud:



(Diesel pickup at top, ABF pickup at the bottom)

Note that most of the marks in the pic of the sump are from where I attempted to create my own hollow with a hammer, unfortunately hindered by the big steel plate welded on underneath    - there where originally just 4 distinctive scratches from the ABF pickup itself.

So, I fitted a diesel pickup - an unclogged one, not the one pictured! I didn't have any plastacine to hand, but using some tin foil and eye judgement, I reckon the pickup still sits slightly to the right of the hollow - but I am satisfied that it now won't foul the bottom.

Fill her up with oil, start her, and the light is still flashing.

So I buy a couple of new oil pressure switches, and fit them.  Light still flashing.

Then I unplug the clocks and check the voltages of the 2 sender wires at that end (to detect any wire breakages). 

Engine off:
Blue/black = Earthed
Yellow = Open

Engine on:
Blue/black = Open
Yellow = Earthed

This suggests to me that the switches are recording the pressure as normal? Or not?  They don't vary with revving etc.  Maybe both my clocks are dud?  Altho my diesel clocks worked just fine before putting the ABF in.

I think I might know someone who has an oil pressure gauge, will find out tomorrow.  If not, I'll be ordering a new oil pump - shall I go for ABF as standard, or KR to match the steel sump?

Thanks in advance,
Calum.

PS: Switched the sender wires over just to humour myself, and light still flashes steady as ever.

[rubjonny]

there is no problem fitting a steel sump to an ABF, the exact same oil pump is used on the 9A and they use the same steel sump as the std 4 pot engines. looking at your pic it looks liek your sump is a bit distorted from the welding process maybe thats what has happened here?

as for oil light issue, if it really had low oil pressure and you drove it for that long the engine would be dead.  check the part numbers and pressure ratings from the sensors, there are lots of different sensors with different ratings. one should be .025-0.3bar, the other should be 1.8bar.  Also, some MK1s have the 2 opil pressure switch wire colours swapped over, so worth a check of that too.