Oil light flashing!!!! Now solved

[Woodyyellow]

Hello everyone.
As this is my first posting on the forum, let me introduce myself.
I am a recently retired Design and Technology teacher living in South Devon. We - my wife and I - have bought a 1987, T25 1900 petrol EMC conversion (I think it's EMC, I'm sure someone will correct me if necessary when I post some images!). We hope to use the camper at weekends and holidays in France next year.
As well as sorting problems created by some of the last 14 owners(!) my main problems are with the instruments so can anyone help please?
Oil light(!) - this must be one of the most common questions I have seen on the forum, but so far I have not seen a solution to my problem.  With the engine running the oil light continually  flashes at a rate of once per second.  The last owner had it checked by a garage who said there was nothing wrong and to just ignore it!! Not something I am prepared to do. Any ideas?
The temperature gauge refuses to move or show any change.  A new clock, fuel and temperature gauge along with damaged PCB ribbon have been replaced. Wires from the sender have been re-attached but still no show!
Finally the analogue clock does not work. This has been replaced due to a previous owner butchering the back and damaging the PCB. The fuel gauge is fully working.
Sorry for this post being so long but I am unhappy using 'Primrose' until these issues are sorted.
Thanks in advance for your replies. 

[Aidan]

oil light flashes before engine starts and should go out when engine starts, this is because the low pressure oil sender (between pushrod tubes above the protective shield on number 3 and 4 (left side looking forward) is registering that you have more than 3psi of oil pressure - failure to go out is either a pcb fault (sounds likely with yours) or a wiring fault or the engine is suffering from terminal oil pressure fault
to trace this you really need a decent manual, ideally a copy of the Bentley manual which has aproper fault finding and diagnosis procedure for testing all this stuff, the garage that said it was alright was being economical with the actualitie, just couldn't fix it and ran out of patience
Bentley manual is available as pdf file from various sources, the paper copy (900+pages) is around £60
Temp gauge again is either a faulty pcb or faulty wiring, yellow with red wire from the engine temp sensor, if unplugged from sensor and put to chassis earth should send gauge to max and cause temp light to flash, if it doesn't then either a wiring or pcb fault
clock just needs a power supply, I haven't got manual to hand so can't remember which track on the pcb edge but number 5 rings a bell, it is often burnt out as permenantly live
the edge connector of the pcb is liable to damage, the more times it is unplugged and plugged in the worse it gets

to track down and fix these sorts of faults could easily take someone who has the info and the knowledge and the patience a day or more even, but it would be a great way to get up close and dirty and familiar with the vehicle yourself if you have the time and the patience (you have the motivation) yourself - the more you can do for yourself the more confidence you will have to go long distances in it, it's not rocket science well within your skill set so I'd recommend a good read of the wiki on here and the Bentley manual; Haynes can be useful and better than nothing but Bentley is the original VW dealers handbooks in one big book, lovely thing imho and better than any of the manuals produced for newer vehicles - the T4 version is horrible by comparison

[Oldiebut goodie]

https://club8090.co.uk/forum/viewtopic.php?f=7&t=110469

[Woodyyellow]

Can I just say a big thank you to you both for taking the time to respond to my question.  As you say, perhaps the fuel gauge and the clock problem should be easy to solve with a little time and logic applied, but the oil light could be more problematic. However I will work at it and report back progress. It's good to know that there are forum members happy to help. 

[Ian Hulley]

Welcome to the Club

Ian

[slowcoach]

bravo aidan!

[Plasticman]

if you want to put your mind at rest and i would , then get a wet guage fitted to test the pressure to confirm all is well , that will also rulke out low pressure as a cause
mm

[Woodyyellow]

Hello.
I can now give a full update to the problems first mentioned way back in November. It has taken much longer than I had wanted due to many, many other things getting in the way!
So.............the clock was not getting any power due to one of the many previous owners cutting the power supply off at the radio connection, in order to fit a new radio, not realising it continued a power supply into the dash! Solving this also gave me back the dash lights.
Then the temperature gauge was solved by replacing the sensor in the thermostat housing. The old one having given up; I do need to fit a new connector on the end of the leads.
Finally the oil flashing light turned out to be the wrong pressure switch being fitted! A black  code one - being normally open, only closing at 1.5 bar! The correct one being blue code, being normally closed, opening at 0.3 bar.
I have learnt so much about the engine and systems through solving these problems, I now feel as if I am starting to know my way around my van! Thanks to all on the forum and those who replied and helped me. I continue to read and learn every day.