Hoping someone can help with my engine swap, originally a GU, now 1Y diesel. I need ignition 12v for the stop solenoid and to drive the glowplug relay, which I see from the FAQ can be taken from the TTV or overrun valve, however, The 2 temperature senders, does anyone know what temperature they cut off at? Reason I ask is the later VW mechanical pump diesels have a simple glowplug relay that cuts off when coolant is at 40 degrees. This is handy as it appears one of the senders can fit straight into the coolant flange on the diesel, and obviously the wiring is all there. Also, how is the dashboard temperature gauge measured, is it from the side of the radiator? EDIT- Also, anyone know rev counter wiring to the coil? Can you tell I know very little about these petrol models!
Grey thermoswitch on the Driver goes open circuit at 35C, I believe, so that might suit your purposes. Red one goes off at 55-ish. Dash temperature gauge gets its 'info' from the black sender on the underside of the same flange that holds the thermoswitches.
Oh yes, forgot about the 3rd one! Only one slot in the diesel flange though, damn. Any idea at all how long it might normally take to reach 35 degrees, driving off straight away, say at freezing point? I should expand on the rev counter, normally these old diesels take the feed from the alternator, but this has a sensor in the pump, 12v in and 5v out. I'm told this matches the signal from the coil?
Couple of minutes? If it's critical, I could time it for you, but it's certainly not much longer than that. Diesel will take longer, I guess, but I don't know how much. You possibly may need to wait for Sir Rubjonny in the morning for rev counter signal assistance.
That time is perfect, driving a different car (petrol) this morning the gauge starts at 50, was at 70 odd after about 1.5 miles, so even 35 after 1.5 miles would be perfect. Have seen glowplugs advertised with 3 minute 'afterglow' as ideal, so that really is perfect.
trouble is 1y is mk3 lump, so even if rev counter is right signal for mk3 petrol clocks its still wrong for MK2 clocks, you need MK2 diesel clocks and pickup feed from alternator MK2 petrol clocks require a pulsed -ve signal fyi
There is no W terminal on the alternator for the rev counter (I know a terminal can be made), but there is a start of injection sensor on the pump which does send out a pulsed signal
all mk3 alts have the W terminal, notice on it you have a 2 pin plug with only 1 wire, add another wire and hey presto if its a pulsed -ve signal it may work, but you mentioned it was 5v?
Ah, that plug was smashed in transit (don't use bungee cord to hold an engine!) There is conflicting information about its output, but seems something else would be needed. I'm so rubbish with car electrics. If its pulsed -ve (twice per rev?), then the rev counter gets +ve all the time but is grounded twice per rev? So in theory, if I had a fast enough acting relay that can switch the -ve by 5v, could it work?
