Very pretty. Did you have any difficulty sourcing the fittings and line? So you simply replaced the sender with the fitting, just like the Wilkinson does?
Parts came from Seven Enterprises:
The line:
Plastic is also available & cheaper. I initially ordered plastic, then chickened out.
The fitting:
Parallel threads are also available, I went with taper. I think both work.
A washer may or may not be required at the gauge. I did not buy one and cannot recall if I already had one or didnât need one:
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Sweet thanks! I think you were wise to avoid plastic tubing. Itâs not just the risk of a mess. Itâll also result in a flat bed ride if it bursts. Did you have to use a used gauge or are they available new?
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Lotus used a 0-60 psi mechanical gauge on some cars. Many write ups regarding parts,hose routing, and parts sources in the archives. I used Mini Mania. The new âsmithsâ 0-100 psi mechanical gages are junk in my experience.
I bought a used TR6 gauge from eBay (about 25 bucks IIRC).
Then the seller lost it and refunded my money. Then a month later he found it and sent it too me no charge.
Thatâs a seller going above and beyond.
Question for all. Does the temperature of the sending unit affect the operation of the sending unit?
Kevin. Iâve tried oil sender units from both the usuals with no success. I then purchased the oil sender that you pictured from Nisonger because itâs a Smiths unit. At first the oil pressure read high but then settled down to normal pressures.
After 12 months is started to act up so I then installed a Smiths mechanical OP gauge on the bracket on the RHS of the radio console. It reads consistently all of the time.
One week ago my oil new Nisonger oil pressure sender started acting erratically and is now all over the place. It lasted 18 months and 2000 miles.
My recommendation would be to install a mechanical gauge and you can get all the parts to hook it up from Merlin Motor Sports in the UK.
Andy 69 FhC
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Itâs not supposed to, but it seems to with the aftermarket ones weâre all suffering from. Another thing Iâve noticed is that though the design is supposed to automatically compensate for voltage variations (see Service Manual description) and therefore is not powered by the 10v voltage stabilizer, my latest âOEMâ replacement reads lower when my cooling fans are on. There is a definite correlation between the Battery voltage and the Oil Pressure reading. Like many of us, Iâve just become used to the behaviour of the gauge, and have a mechanical gauge plugged in under the bonnet that I use as a a cross-check if the cabin gauge behaviour surprises me.
-David
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David, my âSmithsâ OP sender was reading very accurately this morning when cold. After a 25 mile drive and sitting for 1 1/2 hours it was all over the place on the way home. It pegged all the way to the right (the needle disappeared) so I would say that itâs affected by temperature. BTW I donât have mine connected through the voltage stabilize, should it be? The wiring diagram only shows the water temp and fuel gauge through the voltage stabilizer.
Andy 69 FHC
Andy,
No. The oil pressure sender/gauge should not be connected to the 10v stabilized voltage. I think this is what I said in my post, but maybe it wasnât clear. The Service Manual states that the sender/gauge combination automatically compensates for voltage variation, though in my experience that compensation doesnât work too well on the current replacement senders. Like you, I find my electronic sender/gauge reads pretty accurately (as compared to a mechanical gauge) when the engine is cold. As it warms up, the electronic gauge reads lower than the mechanical one. This behaviour is repeatable, and has just become something I acceptâŚ
-David
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Mine reads differently if I go over 3500-4000 rpm. Once I breach that range, even if I then only drive at 2000-2500, the gauge starts dropping and, as noted earlier, will even show zero pressure at idle even though there is clearly oil flow. The next morning, all is back to normal. Oh, and this behavior is, of course, intermittent. I love old cars with new parts that donât work as well as the parts they replacedâŚeven though the parts they replace werenât working well.
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Almost the exact same way I plumbed Tweetyâs OP gauge: leaks are only an issue if thin nylon tubing is used.
But, each to his/her own, eh?
Morning Kevin,
Mine exhibited similar behavior when I had it wired to the IVR, took me a long time to figure that one out. Good luck, hope yours is as simple.
Cheers,
LLynn
Yesterday, as another peace of mind experiment, I checked my sending unit and Smiths gauge against a known accurate mechanical gauge on a home built test stand using compressed air in place of oil pressure. I jumpered the sending unit while out of the car into the carâs wiring harness. At any indicated pressure, 0-60 psi, as indicated on the mechanical gauge my Smiths gauge read about 15 PSI less.
John,
What did you use as a power source for your sending unit/Smithâs gauge during this bench test? I ask, as the readings may be affected by the supply voltage (as per earlier discussion in this thread). If the power source was the battery in the car (not running, presumably), the supply voltage would be lower than under normal running conditions with a charging alternator.
-David
Mines not wired to the IVRâŚwish it was that simple.
That is what I used, exactly as you described it. So I was seeing 12.6 V. Phase II of the experiment will be to acquire a TEE with the proper threads and install both the sender and mechanical gauge on the filter head and compare with the engine running.
I wonder? Do you think a 1 volt difference would make a 15 lb. difference in readings?
I doubt it too. In my experience when my engine is hot and the fans come on, I see something like a 5 psi drop in registered pressure on my gauge. My reason for the comment was my (usual) pedantry about scientific experiments. If the conditions arenât exactly the same, the results may differ. I also agree with you that independent of any voltage issue, my electronic gauge which reads close to the mechanical one at startup, reads about 10-15psi lower that the mechanical one at the end of a long run.
-David
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David⌠and allâŚ
Just seems to me that the guy who designed the electronics for the O.P. gage should be given a âspecial awardâ for his efforts!!
LLo⌠ummmm, Joe
A step backward, after making a wrong turn, is a step in the right direction.
Kurt Vonnegut
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Thanks, sounds logical to me.
As soon as I find a source for a male-female-female 1/4-19" BSPP TEE Iâll order it and find out.