Next oil change looking to install a Mechanical Oil Pressure
Gauge as highly recommended by listers. Saw the archives and
ordered the pluming parts (thanks Chuck).I will order a
Smith gauge and I want to mount it by my ignition switch.
Does anyone know the length of tube I need and where to get
it? I don’t think 49 inched would do it. Any other ideas
would be greatly appreciated.–
Benny 1968 4.2 S11/2 OTS
Old Bridge NJ, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
In reply to a message from BTR sent Sun 24 Mar 2013:
Hi Benny, did the same on my 71 FHC and mounted the gauge under the
dash… next to my left speaker grill. It has green-backlight,
works well and can only be seen by the driver.
My recommendation is to use copper, not the plastic that comes with
the gauge, you will need about 6’. Route it from the oil filter
cannister back to the firewall, just under the top lip using
electical wire clips and self tapping screws, then through the
firewall near the drive shaft hole.
The mechanical gauge come alive instantly and give a fairly
accurate reading of what is going on while waiting for the rest of
the dials to wake up. Brian mytype–
The original message included these comments:
Next oil change looking to install a Mechanical Oil Pressure
Gauge as highly recommended by listers. Saw the archives and
–
mytype
Kelowna, B.C., Canada
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
In reply to a message from BTR sent Sun 24 Mar 2013:
Hi Benny,
I also followed Chucks article and installed a mechanical
gauge. I purchased off ebay a used gauge from a Triumph. I
think it was a TR6. Its styling matched the Jags and I
think mine reads up to 100 lb. I didn’t hide the new gauge
but instead just replaced the electrical one. In hindsight
the only thing I would have done different from Chuck’s
write up would be to eliminate the engine block fittings
which allowed for the electrical sending unit to remain.
The mechanical one seems so instantaneous and consistent
that I don’t feel the need for the electrical one. I’ll bet
49’’ capillary tube will be OK. I don’t remember what length
I used but mine came from a cheap autopart store mechanical
gauge. You could do a test run just using some stiff
electrical wire to measure the distance. I left some coiled
slack behind the dash to allow the dash to drop and I put
some extra sleeving over the tube where it goes thru the
firewall. I think I found an unused screw hole in the
firewall and didn’t need to drill anything. Te only issue I
had was that the used Triumph gauge was missing some fitting
on the back to connect to the olive and nut on the
capillary tube. In this case I got lucky and found a
fitting in my parts bin of old Sunbeam gauges.
Dave Reina
Brooklyn, NY
67 ots–
The original message included these comments:
Next oil change looking to install a Mechanical Oil Pressure
Gauge as highly recommended by listers. Saw the archives and
ordered the pluming parts (thanks Chuck).I will order a
Smith gauge and I want to mount it by my ignition switch.
Does anyone know the length of tube I need and where to get
it? I don’t think 49 inched would do it. Any other ideas
–
David Reina
Brooklyn, NY, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
Has a capillar water temp and mechanical oil gauge. I placed the
gauge instead of the water temp gauge, so I have the standard oil
gauge also in place. I think next to oil pressure water temp is
just as important to know. It works very good.
I use the plastic oil pipe and fitted it in one of the gallery
plugs. No problem. Remember when using copper instead of plastic
line, you need to shield or cover it to prefend a short circuit.
Also remember you can simply reverse the gauge to original.
Regards,
Richard–
The original message included these comments:
Next oil change looking to install a Mechanical Oil Pressure
Gauge as highly recommended by listers. Saw the archives and
ordered the pluming parts (thanks Chuck).I will order a
Smith gauge and I want to mount it by my ignition switch.
Does anyone know the length of tube I need and where to get
it? I don’t think 49 inched would do it. Any other ideas
would be greatly appreciated.
In reply to a message from BTR sent Sun 24 Mar 2013:
I would be very interested in what differences the mechanical gauge
readings showed as compared to the old original electrical readings.
Do they show an increase in pressure? More or less fluctuation?–
larry 71 sII
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
In reply to a message from larry 71 sII sent Mon 25 Mar 2013:
Taking a clue from the earlier cars which had a machanical gauge,
it might be a good idea to fashion several loops or coils in the
copper line to allow for engine torquing…preventing work-hardening
(not to mention outright breakage) of the copper line by spreading
that engine movement over many inches/feet of metal line. The
early XKs have/had steel O/P lines but still had several coils
wound into them. Also, it was quite common for many older cars to
have a flexible line from the engine to some fixed mounting point
on the frame, THEN a hard/stiff metal line to the gauge. Something
to consider IMHO.–
Lee140FHC
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
In reply to a message from Lee140FHC sent Mon 25 Mar 2013:
Some good ideas for the tubing. Do you need flaring and
bending tools for the copper? I would think the plastic line
would be sufficient . I will check it when I get it.
Thanks–
The original message included these comments:
early XKs have/had steel O/P lines but still had several coils
wound into them. Also, it was quite common for many older cars to
have a flexible line from the engine to some fixed mounting point
–
Benny 1968 4.2 S11/2 OTS
Old Bridge NJ, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
In reply to a message from BTR sent Sun 24 Mar 2013:
Benny,
The stock tube length is I think 7 feet but there are 2
different gauge end, depending on the gauge - one gauge,
common for Smiths is a for a flat connection and the other
is conical. I think mine came with the Smiths gauge (dual
water temp and oil pressure.
I just got these guys to make a hose for me - braided as
going to a single op gauge - in the mail so just waiting.
More expensive than the plastic but didn’t really want to
deal at any time in the future with a ‘‘leak’’.
Regards
Keith–
The original message included these comments:
Does anyone know the length of tube I need and where to get
it? I don’t think 49 inched would do it. Any other ideas
would be greatly appreciated.
–
Keith Bertenshaw
Rockaway, NJ, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
Is there an adapter available to be able to connect the mechanical oil pressure gauge to the same outlet as the electrical sender?
If not where does one connect the mechanical gauge to?
There is an adapter for 1/4" BSP male thread (which is what our oil filter housings need) to 1/4" NPT female threads; this way you thread the mechanical oil gauge’s feed pipe fitting into the female portion of the adapter just above where the old electrical one would be installed. Just google the adapter and you should see several sources show up.
Not sure if you want to replace the electrical gauge with a mechanical or just add a mechanical and keep the electic. But either way the answer is ‘yes’.
Not what I did & not my photo but I saved this from someone here when I was deciding what to do:
In the end I replaced the dash gauge with a mechanical from a TR6 using braided tubing and adapters available from MiniMania &/or Seven Enterprises. Details available if that is more the direction you’re going.
There are many threads regarding installation of a mechanical gage. This post within one of them has a links to a parts sources. Oil pressure gauge testing
I’ve used the nylon tubing that typically comes with the gauges for years without any problem in numerous vehicles - never a leak! Advantages include plenty of flex for dropping dash panels and no danger of shorting out electrical connections behind the dash.
Again no issues of metal fatigue from engine vibration or torque flexing, and much easier to thread from oil filter location up to the dash. I encased mine in some slightly larger ID nylon tubing to protect against chafing.
I installed my mechanical oil pressure gauge on the right side of the radio console using the plastic tubing and have had no leaks at all in over 2 years. It’s a great way to verify the accuracy of the original one.
McMaster Carr for fitting.
Gauge Guys put the OE face on my new Smiths
Mechanical. No need to have a couple OP gauges. Have them test it before shipping.
As we know plastic lasts a long time in the marine environment. My capillary tube is 15 yrs and counting under the hood of my car. I’m sorry bonnet! Well grommets and sheathed, however.
Or this one from the UK if you want to keep the electrical gauge and tee in a mechanical gauge. It cost me 17 pounds including shipping and 8 of the copper sealing washers. Took about a week to get to me in Houston.
