electric jiggery pokery

[theelanman]

1. Do nothing. Mentally convert the reading to its correct value so that a reading of around 35 psi is actually 60, 15 psi is actually 25, etc.

yep this is what I do...and it doesnt bother me as I know.......however I am still thinking of selling the car and it just sounds like a crumby story/excuse if anyone asks why the oil pressure is so low......

2. Acquire a 100 psi gauge. These were used on several vehicles, and used and even NOS units pop up on eBay.

...thought about this......think it may look odd as still only the very bottom bit of the gauge is used.......may still go this route

3. Acquire the proper 0-60 sender (and optimally, return the wrong part). There are enough shops that rebuild Smiths instruments that you will be able to find one that has the correct sender. There are links to two vendors in an earlier post.

Ive asked about the propper sender........I think if I find a supplier then I could make my fortune from it...
on the other hand Im now just going round all the manufacturers and asking for their details of their 60psi senders......

I may be at this a while......

[lsdweb]

Gareth

There's a lot of information on the Race Technology web forum. Race Technology's sensors for their data loggesrs are preety expensive so a lot of people, myself included, try to use others.

There's a fair bit of information, including data values for VDO sensors at http://www.race-technology.com/forum/viewtopic.php?t=471

ETB instruments sell the range of VDO sensors at reasonable prices - http://www.etbinstruments.com/Sensors_ancillaries.htm

Regards

Wyn

[theelanman]

good find.....
I think I may have found something.......
just need to check on the size of the threaded end......
I can remember........but Ive now got 3 different figues and I dont now know which one it is.....
1/8th, 3/8th or 1/2..........

anyone???

[bob_rich]

Hi

been following this post on the oil pressure sender for the elan +2. I thought the oil pressure sender was not a resistance v pressure unit but a pulsing generating v pressure type unit.
as the pressure changes so the pulsing frequency varies. The +2 handbook refers to a possible problems with the +10V regulator ( also a pulsing type regulator) that feeds this and other gauges and the pulsing frequencies can beat together and make the pressure reading slowly vary.

Dont suppose this helps much !! but it does mean that resistance checks on the sender may not give the complete picture. I suppose these days pressure v resistance senders are more common but I think that the original gauge was used with the pulsing type sender.

Best of luck

Bob

[john.p.clegg]

Bob

I think you are spot on there, but there is a biasing resistor in there as well.I remember a few years ago my pressure needle was "dancing" all over the place,really had me worried about oil pressure........changing the voltage stabiliser/regulator to solid state fixed that one....as you said,or didn't say "harmonics"

John

[theelanman]

quick up date.......

I bought one which was said to be a +2 sender.......didnt fit...
not sure which +2 it came out of but the thread was bigger than the paul matty one which fitted straight in no probs (but was the wrong pressure rating....100psi)
upon talking to my friendly classic car garage....we discussed this sender
he hit upon the fact that the old rovers/land rovers used a 60psi gauge....
anyway long story short......
rover p1.......fitted straight in.....same resistance as the one john has fitted (going off the values he gave me) so the reading is now back to where it should be..............
40psi when cold then about 25psi when warm
happy chappy......

result

[alexblack13]

Twink should have around 40 - 45 psi hot.. 25psi hot sounds a little low..

Thats my thinking anyway guys..

Alex B....

[msd1107]

Alex,

Different engines may show different readings. For instance, some Aston-Martins came with 150 psi gauges.

My Jaguar MK II had a gauge reading to 100 psi, but spent its time at 40 psi when warm and the revs were up. At idle it was under 10 psi, close to the peg.

Some Elans had 50 psi oil pressure gauges, and some had 100 psi. With a 100 psi gauge, all the time was spent in the lower half of the gauge.

Many twincs show 40 psi when cold and at high rpm when warm. At idle when warm, readings under 20 psi or less are common.

You can fit a high pressure oil pump if you do not like those oil pressures. But modern oils have quite enough film strength to protect your engine at pressures even lower than 20 psi, and there are less pumping losses using lower oil pressures.

Also, the newest oils are (instead of the old 30, 40, or 20/50 grades) 10/30, 10/40, 5/30, or even 0/20. The important thing is to circulate enough volume of oil to lubricate all the surfaces and extract heat from the hot spots.

But some people are not comfortable seeing these low oil pressures. So for peace of mind, get an oil pump that sustains the pressures with which you are comfortable, and run an oil with sufficient viscosity to sustain these pressures.

David
1968 36/7988

[theelanman]

I'll check my pressures again tomorrow when I give it a propper run......
I fitted the sender first........its been fluids change and new filter today.....
engine, gearbox, diff......oh and new cooling fluids.......

its always been 40+ at start and then straight down at warm idle......
I just round it to the nearest 5psi I think its at......

hey at least I dont get 12psi to start with and then about 7psi when warm (might be exacgerating those figures a bit )

[alexblack13]

I thought we were talking std twinks here? & nobody mentioned Idle speed?? That's a different matter.

Still say 40 -45 at running speed though. Set by the pump pressure regulator' spring. High press' pumps = heavier spring.

High FLOW pumps are different again..

Hope this is helpful Theelanman.

Alex...

[theelanman]

I thought we were quoting idle pressures.......its more of a std for everyone.........

anyway...
idle pressures are 40 cold 22 hot
under load 50 cold 40 hot

and yes a std twink....not even the big valve......
the 118bhp version