Just after a bit of advice.....

I installed both an Oil Pressure & Temperature Gauge over the weekend. My question relates to the Oil Pressure sender I installed (under the alternator with an LMA relocation pipe). The gauges and sender are Autogauge. When installing the Oil Temp had two terminals (one for earth) but the Oil Pressure only had a connecting point on the front (direct to the gauge - no connection point for earth). When I started the car after fitting, the oil pressure gauge went to maximum (which I expected) - but it stayed there (even after the oil was warmed up fully). I re-read the install instructions (diagrams only) and one of them has an earth sign & ! I took this to mean it needed earthing. As there are no earthing points on the sender I twisted a cable around the sender body and placed to earth. The gauge seems to work fine now. I was under the impression that the pressure sender did not need earthing (unlike the temp sender). As it clearly does, there must be a better was of doing this than I have by twisting a cable with bared end around the body of the sender and covering with insulating tape (albeit temporary).

The Sender is the following:


Your experiences and suggestions please.

 

Anyone..........?

 

If the sender was mounted directly on the engine then the earth would be directly through to the engine.
Sounds like the LMA extension isn't offering an earthing route. I've got one on mine and can't see why it shouldn't? Have you put loads of PTFE tape on any threads?

nick

 

Yes I used PTFE tape on the threads to ensure no leaks (which there arn't). Never thought of that preventing a good earth which it obviously must have! Thanks for pointing out the obvious!

So, any suggestions on how to earth this in a better way - without disturbing the extenison which is now sealed perfectly, and without simply twisting a cable around the body of the sender?

Just out of interest, how come Oil Temp senders need earthing separately then as these should in theory earth through the block in the same way shouldn't they (presuming PTFE doesn't prevent this, like in my case)?

 

They don't all need a separate earth - its dictated by the gauge manufacturer and which sender they choose.
Nick

 

If its got one pin (like yours) then it earths through the block, if you're using loads of PTFE tape or the sandwich plate is made of an alloy that has bad electrical conductive properties then you'll need to get a large ring connector and remote earth it.