i am going to install an aftermarket oil pressure gauge. i am gonna stick with the autometer z-series since that's what all my other gauges are. if there a problem with using an mech gauge in the cab? i know the reasons would be similar to having a mech fuel pressure gauge in cab, but are the risks the same? autometer doesn't make a full sweep in the electric gauge, only mechanical so i'd rather run the mech for that reason. let me know if this is a thanks again
Mark

 

AFAIK a lot of people use the mechanical gauges. I really hate the idea of having 200-300* oil running into the cab via a little plastic line though.

 

i just can't stand the short sweep on the elec. gauge...
a second question
i am going to be custom designing the dash and the stock gauge will be gone, any reason i can't just remove the stock sensor as well? other than the little red oil light i couldn't think of anything.

 

I'm not sure if that sensor is used by the PCM or for anything else, but I'm sure someone here can tell us.

If it is used, you should be able to add a T in there for your gauge. Adding a T and spacing is not an issue when dealing with pressure gauges (like it is for temp gauges).

 

You shouldn't have any problems with a mech gauge in the cab. Hook up the lines, start the truck and run it awhile, while watching for leaks at the connection at the gauge. Over the road trucks ran mech oil press gauges in cab for years. You could also hook the gauge up at the unused 1/8" plug onto the oil filter adaptor. This is where mine is hooked up. Then you could just leave the factory sensor alone, just in case it does communicate with anything, besides the dash gauge.

 

Do those OTR trucks use plastic or metal lines for the gauges?

I've always been nervous about the plastic lines breaking or cracking in the cab. That would suck.

 

Plastic lines. As long as you run it through a rubber gromet and give the gauge some slack, you won't have to worry about the lines breaking.

 

If you're worred about it, put a shutoff valve on the motor. That way if it springs a leak you can just shut off the gauge and drive.

 

my old 70 chevy has a mechanical guage from the factory, it has a copper line.

 

There are good points about both types of gauge lines.

The metal lines are less susceptible to physical damage, but more prone to vibration damage, especially cracking at the flanges and vibrating holes through them, should they be in constant contact with something else.

The plastic lines will hold up to vibration much better.

If you don't have any leaks on the initial installation of plastic, then you are good for many years.

But, if clumsy bigfoot Barney gets to stomping around in the cab, he could snap off the plastic line, right where it fastens to the gauge.

We have this brainstorm, that people with more authority insist on keeping on the payroll, at our shop.

He jumped in his hotrod junker, one day at lunch, hit the key and socked the gas-pedal to the floor a couple of times.

The little plastic line blew off the gauge and filled his shoes and floorboard with hot oil.

I doubt that this was the fault of the line, but more the fault of the not-too-swift installer.

We laughed about it for days.

 

When I replaced my pressure sender, I had a 12" hydraulic hose made up and put one end into the block and put a tee on the other end. The new pressure sender went on one side of the tee and an industrial type mechanical guage on the other end.
I believe that relocating the sender away from the engine does two things,
it exposes the sender to less direct heat from the engine and less vibration
since it is now mounted on a flexible hose instead of directly into the block.
the guage is mounted near the grid relays so i can check pressure anytime the hood is open for maintenance.

 

A note on tube size . . . .

Running with 1/8" line will dampen the oil pressure variations resulting in a more steady guage reading.

Running 1/4" line will on the other hand show a much more accurate reading in terms of spikes and dips in the pressure.

If you're into bringing it off the line real hard, stacking all the oil up in the back of the pan, you'll have a better chance of seeing the pressure go away with the 1/4" line.






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