Autometer Oil pressure gauge functioning correctly?

[FORD*DIEHARD]

I finally installed my gauges and have a question. 1st, does the clear tubing have to be straight for it to work right? I did not cut the tubing I just left it coiled up but I notice the tubing is not full of oil when the Bronco is on, looks like (air pockets) still in the line (see attached photo of oil line in the can to the gauge.

With that said I have attached photos of the "stock gauge reading and the Autometer gauge reading" , which reading should I trust, they are not even close?

Thank you in advance for your time/help,

Sonny

 

[DirtDonk]

Couple of things that I think, but do not know for certain.
First is that, no, they don’t always fill up and usually there is a lot of air in it, unless you purge it before connecting.
Second though, is that the more air in the tube, and the longer the tube, then potentially the lower the pressure will be up at the gauge. Because air compresses and oil does not.
So if it was mine, I would shorten the tube to what’s needed for clean routing (as long as you have a way to cut it cleanly that is) and put the end in a cup at least to get a little more oil filling the tube. Don’t worry about getting every bubble, just try to get more oil in it.
Then re-connect it to the gauge.

Your reading seems a bit high on the stock gauge, but it’s not far off if that’s a cold start up with thick oil.
What weight oil are you using, and was that picture taken during an initial stages, or was the engine fully warmed up?

 

[Timmy390]

All my after market oil gauge lines have some air in them (Bronco, Samurai, Mach 1). When you turn off the engine, oil will drain back because the oil pump is no longer holding pressure on the engine galleries. The gauge being higher than the connection on the block lets the oil drain and as it does air replaces it.

I don't trust stock gauges. Too many variables. I've always gotten slightly different readings just by changing the sender. Also the stock oil gauge is adjustable. If you take it apart you can change the calibration and make it read what you want. I'm guilty of this on my rig.

Now while I do run the nylon lines that come with the gauges. Copper line is best as it don't degrade over time with heat and time. I've never had a leak (knock on wood) but know a few that have.

Tim

 

[DirtDonk]

Both the factory gauges and the aftermarket auto meter stuff are known to be pretty good. But they’re also known to be pretty inaccurate sometimes.
We’ve talked about the aftermarket stuff and what we might be able to do to fix it, but the factory stuff could be an issue with the sending unit, or the IVR sending out too much voltage.
I’ve seen that, but if that was the case, the other two gauges would read slightly higher as well.
Only way to know for sure is to measure the output voltage coming out of the IVR.

 

[bmc69]

Despite the misinformation...air in the oil pressure line never, ever affects the pressure seen by the gauge. Static pressure is static pressure. The medium/media is irrelevant.


Never use that nylon line that comes with the gauges. I have a video somewhere of how easily a brand new line crumbled in my hands after taking it out of the package. It gets very brittle simply with age. Use the copper line kit.

 

[DirtDonk]

Well there ya go. Educated reality about air’s ability to compress having no relevance to, or effect on the fine workings of a gauge.
Wasn’t sure, but always thought it could be a thing.

 

[FORD*DIEHARD]

The photos of the gauge reading were after driving around for about an hour. I have 10-40 oil in right now. I'm in SoCal , I know the weight of oil changes where you live depending on weather. Is that a good weight to be using?

So, what should the "pressure " be "normally " and what would a "turn it off DANGER pressure be low and high, if that's possible?

I have attached the setup, it's an extension with the stock sensor and the autometer tube connection. I thought about running the copper line but heard you dont want "sharp bends" and it's not a straight shot from the sensor into the cab , that's why I went with the nylon line. Anyone have pictures of how they ran their copper line?

Thank you in advance for your time/help,

Sonny

 

[OX1]

I finally installed my gauges and have a question. 1st, does the clear tubing have to be straight for it to work right? I did not cut the tubing I just left it coiled up but I notice the tubing is not full of oil when the Bronco is on, looks like (air pockets) still in the line (see attached photo of oil line in the can to the gauge.

With that said I have attached photos of the "stock gauge reading and the Autometer gauge reading" , which reading should I trust, they are not even close?

Thank you in advance for your time/help,

Sonny

How old is engine? (when were main/cam bearings and oil pump last replaced)
Cold engine or hot?

 

[toddz69]

I'm not a huge fan of copper either as I always worry about it work hardening and cracking over time due to vibration. I've used a -3 stainless braided teflon line (brake line) for mine. Easy to route with a bulkhead fitting on the firewall to get it into the passenger compartment.

Todd Z.

 

[FORD*DIEHARD]

The photos of the gauge reading were after driving around for about an hour. I have 10-40 oil in right now. I'm in SoCal , I know the weight of oil changes where you live depending on weather. Is that a good weight to be using?

So, what should the "pressure " be "normally " and what would a "turn it off DANGER pressure be low and high, if that's possible?

I have attached the setup, it's an extension with the stock sensor and the autometer tube connection

Thank you in advance for your time/help,

Sonny

 

[Timmy390]

Oil pressure varies but generally, the ideal oil pressure is between 25-65 PSI so I read.

Old Timers will tell you 10PSI per 1000RPM and you're good. I like 30-35 at hot idle. I see 50-60 on my Samurai, Bronco and Mach 1 at cold idle. My 2500HD is almost 90 at cold idle. Hot idle Samurai is 25 (the 1.3L is tired), Bronco is 40, Mach I is just under 40 and 2500HD is 30

Tim

 

[DirtDonk]

Then the reading on the auto meter gauge is pretty close to what would be expected in a healthy engine.
With that weight oil, you should see approximately 60 to 70 psi on the cold start up and 30 to 40 after fully warming up. Maybe 45 for a while.
A 10W-40 should be fine. I ran 20 W 50 in mine even in winter and it worked excellent, but would definitely be considered a little on the thick side for a healthy engine.

 

[OX1]

The photos of the gauge reading were after driving around for about an hour. I have 10-40 oil in right now. I'm in SoCal , I know the weight of oil changes where you live depending on weather. Is that a good weight to be using?

So, what should the "pressure " be "normally " and what would a "turn it off DANGER pressure be low and high, if that's possible?

I have attached the setup, it's an extension with the stock sensor and the autometer tube connection

Thank you in advance for your time/help,

Sonny

New bearings/oil pump, cold oil, I've seen 100 PSI guage practically pegged.
When warm though, right around your 40 PSI number (maybe 30 warm, low idle).

Worn/old engines and/or very hot/thin oil, could be 70 cold and 15-20 idle.
Appears your stock guage is off to me.