Author Topic: Gauges...which ones?  (Read 2406 times)

February 11, 2018, 07:07:15 pm

bpcaddy

  • User+

  • Offline
  • *

  • 30
Gauges...which ones?
« on: February 11, 2018, 07:07:15 pm »
Can't find any thread about this but figured it's interesting.

Which gauges are necessary to prevent damage?


Egt - to monitor turbo boost/heat
Cht- to monitor engine block heat

I think that's all I need.......except good oil level sensor would be nice for failures....and maybe volt meter to save my battery

I read there are egt gauges w/alarms but I just got aviation westach gauge



Reply #1February 11, 2018, 09:44:29 pm

ORCoaster

  • Moderator
  • Veteran

  • Offline
  • ***

  • 4437
  • Personal Text
    Restoring a Caddy as time and weather allows
Re: Gauges...which ones?
« Reply #1 on: February 11, 2018, 09:44:29 pm »
In the olden days when engineers were more in control of the dashboard layout they wanted to see at a minimum an Oil pressure, Water Temp and Voltmeter for the drivers to see.  Option packages usually contained the tachometer and the odometer trip button.  As car manufacturers started to crank out more base model cars and the option packages became more about creature features the gauges turned into idiot lights or warnings. 

Warning your oil pressure is low, opppsey too late!

Dad was a Ford test engineer in the fuel injection and carb division.  He cussed under his breath every time he bought a new car (once a decade was good enough), that they didn't include enough gauges.  So he always had extras in the workbench ready to install.  I remember one time he brought home this test Lincoln and you really couldn't sit in the passenger seat for the panel of gauges installed there.  Granted they were monitoring everything but the sheer number was just so cool to look at.  Talk about driver distraction.  Seriously, pressure gauges for fuel, at different points of the engine, coolant temps at the bottom of the radiator and engine block and vacuum for engine and brakes. 

So for starters on my car I do an oil, water and volt.  Then step it up to the EGT and amperage gauges.  When I ran veg oil I had temp at the tank, at the pump and outside.  Those were digital and very nice.  So it just depends on how much information/distraction you can bear.  I don't need to know the internal working pressure of the IP anymore but I had that at one time just to be sure the advance was working correctly.  Do you want to know how hot the oil is as well as how hot the coolant is getting?  Temp gauges on both liquids then.  Or a switch to flip the sender information to the same electric gauge.  But I despise those over a manual gauge.

There is only so much room on the dash, on the pillars and such to properly locate the faces of the gauges.  I had nine in front of me on two different panels in the Rabbit on Veg oil.  That car now only sports a tri panel with the volt, oil and water temp gauges on it.
It is up to you but I like more then less.  On my Caddy I have EGT and Water temp just under the radio on the dash and an Amp, Volt and Oil pressure on a tri panel in the console.  I would like to add a turbo in the future and likely do a pillar boost vacuum gauge there.  With a solenoid to control boost or vac from the fuel system.

Let us know which way you go.

Reply #2February 12, 2018, 03:34:52 am

Rock3tman

  • Junior

  • Offline
  • **

  • 113
  • Personal Text
    prev: 60typ2, 68pickup, 79rabbitD. now: 83jettaTD
Re: Gauges...which ones?
« Reply #2 on: February 12, 2018, 03:34:52 am »
CHT (cylinder head temperature) is much more important in aircooled engines - and these days aircooled engines are almost exclusively aviation related.   Especially highly stressed engines like those on large propeller driven airplanes...

For this lowly VW IDI driver, an EGT and turbo boost are all the extra gauges I need above the usual oil, water, RPM, quantities, & electricity ones.  To supplement the stock cluster with tach instead of clock, I also run VDO mech oil pres, elec. oil temp & voltage gauges in the console, and the column mounted EGT/Boost in a one gauge westach 2 1/4" gauge offering with an 1/8" EGT thermocouple pre-turbo.

For liquid propellant rocket engines, no gauges are really necessary: if the automated engine controls don't work, it doesn't matter what you have! 

- Rock3tman

Reply #3February 12, 2018, 09:43:42 pm

ORCoaster

  • Moderator
  • Veteran

  • Offline
  • ***

  • 4437
  • Personal Text
    Restoring a Caddy as time and weather allows
Re: Gauges...which ones?
« Reply #3 on: February 12, 2018, 09:43:42 pm »
OOOOOOOww,  idea time.  Liquid propelled rocket engine build in a 79 Rabbit

Reply #4February 13, 2018, 09:22:28 am

Ruby Doom

  • User+

  • Offline
  • *

  • 26
Re: Gauges...which ones?
« Reply #4 on: February 13, 2018, 09:22:28 am »
Oil pressure, for sure, if you don't have pressure, you have problems ;D

Voltmeter is nice, but not fatal, if you're voltage is low, you'll find out when you go to start, I also like the tractor style ammeters instead of a voltmeter, tells you if you are charging it, or draining it ;)

If there is a way to fit a temperature gauge, that doesn't rely on coolant, that would be nice. Happened to me once, the coolant got so low due to a bad hose, that I didn't know I was overheating. I realized it when I stopped getting heat in the car. (I'm guessing the heater core drained first). So either a non-coolant dependent temp gauge, or a coolant level (or pressure?) gauge.

Reply #5February 13, 2018, 11:39:24 am

libbydiesel

  • Global Moderator
  • Veteran

  • Offline
  • *****

  • 3399
Re: Gauges...which ones?
« Reply #5 on: February 13, 2018, 11:39:24 am »
I used to want more gauges than I do at this point.  I find that gauge watching detracts from the overall driving experience and so I tend toward wanting only what I will need to very quickly diagnose engine critical issues.

CHT (cylinder head temp) is not helpful on water-cooled engines.  Coolant temp would be the crossover from an air-cooled CHT gauge, but the stock cluster already has it.

For volts/amps, I actually find the charging idiot light sufficient.  If the alt isn't putting out more volts than the battery, the light comes on - that's good enough for me.

Oil pressure is another engine critical parameter.  Electronic oil pressure senders seem to fail at an alarming rate and there are several times where I have had significant stress from the electronic oil pressure gauges giving false readings.  I tend to run vanagons and mechanical oil pressure gauges don't work well with the long run and colder weather.  At this point I tend to stick to the dynamic warning system and call that good for oil pressure.  The single low pressure switch system is not sufficient and if that is all that is fitted to the cluster I will add the gauge.

Oil temp is good to run for a bit on a modified engine, in order to make sure it is not getting too hot, but once you have oil cooling dialed in I'd rather not have it on the dash.

On the turbo-diesels I like to run EGT and boost/vac.  EGT will quickly tell if there is an issue with pump/fueling or over-fueling before engine damage.  Using a gauge that reads down to 250°F or below allows you to use the EGT gauge for cool down before shutting off the engine which will also save your turbo bearings and engine oil.  Boost will show any issues with turbo.  Vac side of boost gauge will tell if there is an issue with the intake or air filter that might cause runaway.   


Reply #6February 14, 2018, 10:30:08 am

bpcaddy

  • User+

  • Offline
  • *

  • 30
Re: Gauges...which ones?
« Reply #6 on: February 14, 2018, 10:30:08 am »
Thanks for the reading. Be cool to see all those gauges the engineers use.

 Yeah, Ruby dom not getting temperature reading due to low coolant is why I like the CHT gauge. Coolant temperature doesn't matter, only engine temperature I think. If something went wrong, I'd think the cht would show it first.

Boost gauge to show if something goes wrong with the turbo makes sense, but I don't know a lot about turbos. I'll get one if that's the case.

Egt gauge cause of the immediate feedback and boost monitoring and I hear possible over boosting and warping some things.

I think I'll stick with alternator idiot light for now.


My oil sensor isn't hooked up because it has a 91 eco in the 81 caddy. I will probably add an oil pressure gauge. Also kinda tells the quality of the oil I think.


Thanks :)




Reply #7February 14, 2018, 12:01:23 pm

libbydiesel

  • Global Moderator
  • Veteran

  • Offline
  • *****

  • 3399
Re: Gauges...which ones?
« Reply #7 on: February 14, 2018, 12:01:23 pm »
Do you have the coolant level sensor?  If not, then add it.  With the level sensor, if you get low coolant, the coolant LED will start flashing.  Even with low coolant, the coolant temp will still read fairly accurately assuming you have the sensor mounted in one of the aluminum coolant flanges. 

Running without any warning light for oil pressure is really risky.  You're basically asking for and deserve a tossed rod for that.  You only have to hook up one wire for the '81 oil pressure gauge wiring to work on the Eco engine. 
« Last Edit: February 14, 2018, 12:06:52 pm by libbydiesel »

Reply #8February 21, 2018, 08:05:45 pm

bpcaddy

  • User+

  • Offline
  • *

  • 30
Re: Gauges...which ones?
« Reply #8 on: February 21, 2018, 08:05:45 pm »
Thanks. The aviation CHT gauge seems to be working good though the head temperature is on the low end of the scale.


I'm getting a 10 mm adaptor for my oil pressure gauge to put in the head in place of the dummy light. :)

Also I'm lining up the gauges on the dash above the speedo cluster and will rig some carpet/Towl thing to cover and easily hide them when I leave the truck.

Reply #9February 21, 2018, 10:58:49 pm

ORCoaster

  • Moderator
  • Veteran

  • Offline
  • ***

  • 4437
  • Personal Text
    Restoring a Caddy as time and weather allows
Re: Gauges...which ones?
« Reply #9 on: February 21, 2018, 10:58:49 pm »
pods on top the dash.  See it all the time.  No need to cover.

Reply #10February 21, 2018, 11:10:20 pm

bpcaddy

  • User+

  • Offline
  • *

  • 30
Re: Gauges...which ones?
« Reply #10 on: February 21, 2018, 11:10:20 pm »
I'm just worried it may get stolen.

Reply #11February 22, 2018, 11:05:05 pm

ORCoaster

  • Moderator
  • Veteran

  • Offline
  • ***

  • 4437
  • Personal Text
    Restoring a Caddy as time and weather allows
Re: Gauges...which ones?
« Reply #11 on: February 22, 2018, 11:05:05 pm »
Yeah that is always an issue with our older non-tech theft vehicles.  Mine has one of those old time round key switches on the fender.  I want to put in a blinking LED so people will leave it alone.