Oil Pressure & Water Temp Gauges in my 86 F250 with 460 are DRIVING ME CRAZY!
 

Spent a couple hours searching and reading the various posts about water temp and oil temp gauge anomalies but can’t locate the info I need, hoping someone can steer me in the right direction.<O:p</O:p

When I start the truck when it’s cold the oil pressure comes right up to about ¾ on the pressure gauge however, as the engine warms up the pressure steadily decreases to the point where it is barely above the “L” on the gauge, I rev the engine up but the pressure does not increase. I am fairly certain I have oil pressure because I don’t get any lifter noise, even at highway speeds.

After driving for a while the water temp gauge will rapidly rise, much faster than an overheating engine, then return to normal. The gas gauge will also drop as much as a half tank then return to the original indication.<O:p</O:p

I plan on trouble shooting the original gauges someday but for now I need some advice on installing an aftermarket oil pressure and water temp gauge.<O:p</O:p

Can someone that has added aftermarket gauges to their truck help me by recommending mechanical or electric gauges. If the recommendation is mechanical, can you tell me where I tap into the block on my 460 to install a wet oil pressure gauge and where/how I install a temp sending unit for a mechanical water temp gauge.<O:p</O:p

If you think it is better to install an electric aftermarket oil pressure & water temp gauge, could you describe where I tap into the current electric gauges?<O:p></O:p>
I know a lot of guys frown on running wet gauges into the cab but I am more interested in running mechanical gauges as a backup and repairing the factory gauges at some point.<O:p</O:p

I really don’t want to drive the truck much more until I am sure of where the oil pressure and the water temp are actually at.<O:p></O:p>

Thanks in advance for any help.<O:p</O:p

One acronym:

Ford ICVR

Google it, even search this forum on it. :)

Or, IVR, as that's what I frequently call it. It provides the set voltage to the fuel gauge, oil pressure gauge, and water temp gauge. So, if it changes the voltage your readouts on those three gauges changes. And, they are a known problem.

But, on the oil pressure I'm not sure that explains things. It takes about 30 miles of highway driving for an engine's oil to get to full operating temp, give or take a few miles for the outside temp. So, what is happening is that the oil is thinning as it heats, which is normal, and the thin oil comes through the worn bearings so quickly that the oil pump can't provide enough oil to keep the pressure up. While that doesn't account for the pressure not coming up when you rev the engine, I do think you have very low oil pressure, so highly recommend that you put in aftermarket gauges.

On the gauges, I recommend a mechanical oil pressure gauge as it is so easy. I don't know where the 460's oil pressure sender is, but pull it off, install a tee, and then put the pressure sender in the tee and the tube for the mechanical gauge. And, it doesn't have to be a high-dollar gauge as most are as accurate as they need to be for your purposes.

As for the temp gauge, I'm not sure what to recommend but I think I'd go electric as I don't like the tube that has to run from the gauge thru the firewall to the engine. However, one problem you may run into is the lack of a second point to put a temp sender. My 351W just doesn't appear to have another place to do that and I don't think it is good to put them in a tee as the liquid will cool and not provide an accurate reading since there is no flow.

For the oil pressure not coming up when you rev the engine, these gauges are really slow to react to changes. Think if the gas gauge bounced around as you drove over a curb.

If all three gauges are wiggin' out in unison, that is usually the ICVR's fault.

If they're wiggin' out individually, more investigation needs to be done.

ctubutis,

Thanks for the quick reply. Now that I think about it I ran into the same problem when I was trying to install an aftermarket electric water temp gauge in my friends 65 Mustang. Since I have restored my 70 and 66 Chevelle my friend thought I must be an old car expeert. It wasn't until after he produced his factory repain manual that I found out the Instrument Cluster Voltage Regulator which, was responsable for the voltage pulses I was getting at the gauge. I guess a Ford is a Ford. now all I have to do is figure out how to get the dash cover and instrument bezel out.

One last thing, do you have a source for the plastic lenses that cover the turn signal indacator and other lights. I am missing a couple of the lenses and don't know what ther are when the bulb illuminates. The one I am most courious about is the ons on the far left. The lens is missinf and the bulb is not installed.

The oil sending unit is on the top of the block behind your intake(on the back of the engine).

It will be behind the intake,close to the firewall...

Put in a tee and install the aftermarket gauge..

The temperature sending unit is on the front corner of the intake on the drivers side of the vehicle.
There should be one or two plugs on your intake to put the fitting in for your temp sending unit..

I am giving you this info based on my 460, it is a 77 model engine in a 76 model truck...I don't believe they changed them..correct me if wrong..

Maybe this will help you...Trav...:-wink

What a great forumn, I can't thank you guys enough for taking you time to help me out.

Thanks guys.

People have helped us, so we are helping you. Good luck!

Yeah... in general, a Ford is a Ford. Unless it's a Mazda under the badges, or a Volvo, or a Yamaha, or....

Yeah, I know what you're talkin' about, but no, I don't have a source other than a junkyard.

BTW you don't need to remove the dash pad (cover) to get at the gauges...

Remove the piece of plastic trim underneath the steering column - 2 screws.

Remove the column shroud.

Remove the headlight & wiper knobs:

From Franklin2's images:
https://www.ford-trucks.com/user_gal...oid=24489&.jpg







Headlight knobs, it depends... some come off like the wiper knob above, others are glued to the stalk and you need to remove the stalk + knob as a unit. One does this by reaching underneath and pushing a mechanical button on the switch assembly, thereby releasing the stalk and allowing removal.

https://www.ford-trucks.com/forums/a...1&d=1272210773



Remove the cluster bezel (may have to loosen the dash pad to get at two screws at the top).

Remove I think 4 screws attaching cluster to dash.

Pull assembly forward, reach behind, disconnect electrical connector & speedo cable <-- Might Google that cable removal... it's real easy but I always forget and fight with it, when all you need to do is squeeze in the right places.



I think that's it.... somebody will correct me if I'm wrong....



BTW this is what I did to my 400 to add an AutoMeter oil pressure gauge in addition to the factory one:

http://imageshack.us/a/img216/3954/p1010260z.jpg



For water temp, I added a second sending unit into the water pump in a place formerly used by a temp-actuated vacuum thinger.

EDIT: More here:
https://www.ford-trucks.com/forums/1...te-gauges.html

Come to think of it, I don't think you need to do anything with the cover/pad to get the bezel off, I'm not even sure there are screws up there or not.

Look at it, it should be obvious and present itself to you.

Glad to hear it. :)

BTW could you do me a favor? Go HERE and finish filling out your profile... what you enter in the Location field of the 3rd pane will show up in the top-right of each of your posts. :)

You say potato, I say potatoe, you say tomato, I say tomatoe, FoMoCo says (text section 103, page 22):

D1AZ-10804-A .. ICVR ~ Instrument Cluster Voltage Regulator (Motorcraft GR-513) / Located on printed circuit board / Available from Ford/autoparts stores.

Applications: 1971/86 F100/350 & Bronco / 1971/91 Econoline // Misc 1971/80 FoMoCo Passenger Cars.

When this little charmer begins to fail, the gauge needles may do "the hula" swing back/forth on their own.
------------------------------------------------------------------------------------------------------
E4ZZ-9278-A (replaced: B7T-9278-B, C7ZZ-9278-A & C9ZZ-9278-A) .. Oil Pressure Gauge Sending Unit (Motorcraft SW-1547-B) / Available from Ford/autoparts stores.

Applications: Myriad 1957/90's FoMoCo vehicles with an oil pressure gauge, except diesels and misc I-4 & V6 engines.

This little charmer gets gummed up with dirty oil. The faster it gets gummed up, the slower it is to react. Eventually it gives up the ghost.

iol presser sending unit on the on my 460 was located behind the intake manifold, top of motor block,probably easier to get to with a carb then with mpfi, make sure you use copper line plastic one have never held up for me.

Hey I am working on this part right now and mine was not hooked up like yours mine was done half ass, the pick you have there is that the correct way????