Adding an Oil-Pressure Gauge

[Greg Field]

Since some of the V11 Sport series seem to show symptoms (flickering oil lights) of oil starvation when accelerating hard (thought to be because of their front-mounted oil pickup), I just had to plumb in a gauge to see if Billy Bob was similarly afflicted. I also wanted to keep the stock oil light. Here's how I did it:

 

First, gather all the stuff.

 

 

This photo shows what I used. The gauge is a really good one, but it only reads to 60 psi and has no light. I decided to use it because I valued accuracy at full temp for this project, above other considerations such as seeing it at night and knowing what peak cold pressure would be. Items include the gauge, a brass 12x1.5mm to 1/4 NPT adapter, a brass 1/4-to-1/8 NPT adapter, a 1/8 NPT adapter, and the fittings for the oil line.

 

 

The first step was to tap the 1/4-to-1/8 NPT adapter to 12x1.5mm so I could thread the stock pressure sensor into it. I first drilled it undersized to keep as much wall thickness as possible, and then carefully tapped it, stopping just as the tap's widest part first threaded into the brass. Even with such care, the wall thickness was marginal, so I decided to make both pieces one by using JB Quick Weld as the sealant when I threaded the two adapters together, as shown above.

 

 

The next step was to index the compound adapter so that the 1/8 NPT adapter would exit at the front.

 

 

I then drilled and tapped it to 1/8 NPT, and installed the adapter, using sealing compound just to be sure.

 

 

Here's the adapter in place on the block.

 

 

Next, I improvised a holder for the gauge. I had an old Harley bullet light housing that looked like it would work, so I gutted the housing, drilled a hole in the back of it for the oil capillary tube, installed a grommet to protect the tube, and opened up the front a bit to accept the gauge.

 

 

Here's what it looks like—kinda ghetto, but not as ghetto as the exposed gauge would be.

 

 

Then, I cut, drilled, and bent a little bracket outta stainless and bolted the bullet light to it.

 

 

All that remained was to route and connect the line and protect it with a sheathing of clear tubing.

 

 

Here's the finished project. Not up to Orange County Chopper standards, perhaps, but not bad for a quicky, improvised morning project.

[Ballacraine]

Great!.....Now you got something else to look at to fret about!

 

Seriously.....

 

Neat job.

 

Nige.

[docc]

Very nice! So what kind of pressures are you seeing?

[Guest ratchethack]

Give the man some time to compile his Professional analysis, Docc!

 

He's gotta do a series of drag-strip launches and 2nd-gear wheelies so's to best expose the oil pickup while lookin' at the gauge!

 

Enquiring Guzzisti minds are a-chompin' at the bit!

[quazi-moto]

I'd like to know the pressure readings also.

[Greg Field]

OK, here's preliminary results.

 

Baseline oil is 50-50 mix of 5w-40 Shell Rotella T "synth" with Redline 20-50.

 

On startup on a 55-degree F morning, idle pressure was about 65 psi. It held this pressure (apparently the true blow-off pressure) while I drove it gently for the first 3-4 miles to the first place I had to come to a stop. By then, oil temp was up to 70 degrees C. Idle pressure dropped into hte 45-psi range. Pressure at 3,000 rpm and higher was still over 65 psi.

 

When I got to work after 12 miles, oil temp was 95-degrees C. Oil pressure at 3,000 rpm was 58 psi. Idle pressure was 27.

 

At lunch I took a 20-mile drive on the freeway, not pushing hard at all. Air temps were prob'ly 72-degrees F. Oil temp rose to 110 degrees C. Pressure at 3,000 rpm was 57; pressure at idle was 20 psi.

 

THis is very good pressure. In the future, I'll probably go to all 5-40, since pressures remain at blow-off-valve pressure while on the freeway until the oil reaches nearly 80 degrees C.

[Greg Bender]

Hi Greg,

 

That IS very good pressure! I'm especially impressed with the idle pressure after your interstate run. On both my Quota (35,000 miles) and my Ambassador (~90,000 miles), I get the following values:

 

Idling cold: 60 PSI

Revving cold: can jump to 75 PSI...has really taught me to let things warm up first

Idling hot: 10 PSI or thereabouts. This is on a hot day (95*F +) at an interestate exit after I've been running 75-80MPH for 20 miles or more.

Running hot: 45 PSI or thereabouts. Again, this is on a hot day, interstate run, etc.

Revving hot: the 45 PSI will jump into the mid 50's or higher if I punch the throttle and wind up the revs.

 

Quota uses Mobil 1 15W50 fully synthetic. Ambassador uses Castrol 20W50 Dyno. Neither have oil coolers.

 

I'd be really interested to hear about your idle pressure after an interstate run on a really hot day.

[docc]

GregF, No signs of pressure drop on hard acceleration?

[Distilled Waters Run Deep]

Does the gauge have to be able to take a certain heat range itself -or does the oil cool off enough in the pipe not to have to worry?

[Greg Field]

Distilled Waters: The gauges do not have to take much heat. Here's the second way I added gauges. It works better:

 

http://www.v11lemans.com/forums/index.php?...hl=oil+pressure

[raceboy]

Distilled Waters: The gauges do not have to take much heat. Here's the second way I added gauges. It works better:

 

http://www.v11lemans.com/forums/index.php?...hl=oil+pressure

 

Nice job Greg, Just an observation here, but, you mention you used a gauge rated at 60 psi, but in your preliminary findings you indicate that you see pressure rise to 65 psi......hmmmm???

 

Also in the link shown above you say that you found a nice temp sender (electric / electronic I assume) that fits somewhere near the drain bolt. Can you please provide more details on this sender and the possible installation along with the associated temp gauge.

 

Cheers & Thanks,

 

Raceboy

[Greg Field]

There was no pin stopping advancement of the needle. It went what looked like 5 psi beyond 60.

 

The temp sender fit into the plug in the lower sump that is just to the right of the drain plug. I got it and the gauge and guage mount at egauges.com. I think the thread was 12x1.25 or something like that.

[raz]

I think the thread was 12x1.25 or something like that.

For what it's worth mine (Sporti) is a standard M16 (x1.5) thread. I would guess V11 is identical, but I'm not sure.

[Distilled Waters Run Deep]

Without a thread gauge -the Jackal seems to be a 12 x 1.5 thread to me. I've bought a switch with a spade connector: Intermotor part No. 50570 or XOPS8.

 

Looks right -I've found on another forum "50570 22 M12 x 1.5 2.9-7.3" -the last 2 figures relate to the p.s.i. at which it operates.