Two gauge questions...

[Johnny248]

Two questions about adding some gauges...

First, how much of a difference is there between stepper motor gauges, and regular electric gauges? I read somewhere that steppers are aprox 5% more accurate than regular electric gauges?

Second, Where is the best place to install a sending unit for an oil pressure gauges? Should it be installed in the sump like a trans temp sender? Is that the best place for it?

 

[CBR.worm]

Stepper motor gauges can be very accurate and can be fast. Some of them (Stack?) bother my eyes because the steps are too big and I prefer more fluid movement as long as there is no lag/overshoot or bounce.

There is a huge variance in quality, accuracy and speed for electronic gauges. Many OEM gauges are now stepper motor driven - I generally find them sufficient and would go to a good digital display (like MoTeC) if they were not.

I think it is common to tap oil pressure sender either at the oil filter mount or at the OE oil pressure switch location.

 

[Johnny248]

Originally Posted By: CBR.worm
Stepper motor gauges can be very accurate and can be fast. Some of them (Stack?) bother my eyes because the steps are too big and I prefer more fluid movement as long as there is no lag/overshoot or bounce.

There is a huge variance in quality, accuracy and speed for electronic gauges. Many OEM gauges are now stepper motor driven - I generally find them sufficient and would go to a good digital display (like MoTeC) if they were not.

I think it is common to tap oil pressure sender either at the oil filter mount or at the OE oil pressure switch location.


Hmmm.. I guess for what most people use gauges for, as long as they were somewhat accurate then they would work fine. I would say most people like to watch them because they look cool, so if you have a gauge that has say a 5-10% tolerance on accuracy, say on an oil pressure gauge, the 2.5-5psi difference in reading of an analog style gauge at 50psi is not very noticeable. I think that there are too many variables when dealing with normal consumer 52mm gauges to have anything that is right on. When you think about the width of the needle, the scale of the gauge increments, manufacturing tolerance, and things such as wire resistance and what not, most anything would would be off slightly.

Back to the temp gauge, I was curious because I would think that the sump would give you a better "average" temperature of the oil, where as one of the passageways would be slightly different, higher or lower. Such as a trans temp gauge in the pan vs the feed or return line for the cooler.

 

[MisterBen]

Auto Meter stepper gauges, last I checked, were expensive. Like, $2-300 for a gauge compared to its traditional electronic brethren (which is a little more than mechanical).

T'ing the factory oil pressure sender is about your best bet as mentioned--the sump won't get you a pressure reading.

 

[Johnny248]

Originally Posted By: MisterBen

T'ing the factory oil pressure sender is about your best bet as mentioned--the sump won't get you a pressure reading.


I'm looking for oil temp, not pressure. The pressure gauge was just an example for my gauge accuracy.

 

[Astro14]

Factory oil temp gauge (on my Volvo that had one) was in the sump.

 

[mechtech2]

There is no pressure in the oil pan. You need high presure porting.
Like mentioned, an oil filter adapter is an option.
But easiest by far is to tap with a 'T' fitting at the gauge sender location. Make sure you get the right thread pitch, and use a little teflon tape of permatex #2.
Do not over tighten fittings!

 

[Johnny248]

Ok, I read the original post. I made a mistake. I am looking for an Oil Temp gauge, not pressure. I have my pressure gauge sending unit T'd off of the port from the original oil pressure switch.

My bad on the posting. That is why I was speaking of the sump. I'm not that stupid to know there is no pressure in the sump lol just stupid enough to type the wrong thing in my posting...

 

[MisterBen]

Ahh... As I understand it, the oil sump runs cooler than the oil. so, somewhere in the "oil stream" is best. if there's a good spot in the flow around the oil filter, that should work.

I've struggled with the same thing. It was suggested to use a "sandwich adapter", but I don't like those things as they often leak.

Sump would be OK if you can't find anything else, with the realization that it's probably several degrees cooler than the oil is running in the motor.

 

[mechtech2]

A temp gauge is my preferred oil gauge. Great idea. The oil pan/sump is where you want it.

 

[Johnny248]

Id really like to add an oil temp gauge to go along with my oil pressure gauge. I know that oil pressure is not the most crucial gauge to have in a normal dd, I mean there is a switch to turn on the idiot light if pressure does get low, however I still like to watch it and monitor what the oil pressure is doing. The temp gauge would be rather cool just to have also. I mean, in reality, how often does one really need to worry about oil temp?

If I had an auto, I would also have a trans temp gauge. I have one installed in my old ram, and it useful to monitor temps when I am towing in the summer and whatnot.

Sorry if I'm getting a little off subject, but I am looking to purchase a new truck and have already been planning on what I want to add to it. This being

Oil Pressure, Oil Temp, and Trans Temp. There is a company which makes a cast diff cover which has an area to be tapped for a temp gauge. That would be really cool, but again I don't think it would be rather useful other than something cool to look at.

 

[HTSS_TR]

Originally Posted By: Johnny248
Id really like to add an oil temp gauge to go along with my oil pressure gauge. I know that oil pressure is not the most crucial gauge to have in a normal dd, I mean there is a switch to turn on the idiot light if pressure does get low, however I still like to watch it and monitor what the oil pressure is doing. The temp gauge would be rather cool just to have also. I mean, in reality, how often does one really need to worry about oil temp?

If the oil temp never get above 200-210F in winter months then you can use 1 grade thinner oil. If the temp is below 190F with recommended grade then you can use 2 grades thinner oil, from xW40 to xW20 as an example.