The best way to monitor the engine and compartment.

[rv_safetyman]

David, thanks for the Murphy thought.  A link:  http://www.fwmurphy.com/products/temperature/index.htm

I looked at a bus at one of Jack's rallies and the owner had what he called "alarm-a-stat" or something like that.  I just did a search and could not find anything with that name.  If you do a Google with "alarm + temperature" you will get a bunch of hits.

My point in the previous post was that COMPARTMENT temperature is one more early indicator of a problem.

Pete, I was glad to see that the digi-panel is still on the market.  I talked to the inventor a few times at various RV trade shows, but have not seen him at any show in the last few years.  QUESTION:  how did you deal with the coolant temperature gauge?  When I first saw the unit, I was quite concerned that that part of the panel was set up for gasoline engines and the temperature range was not correct for our two stroke engines.  Other than that, it is a neat device.

Jim

[RTS/Daytona]

Digi-Panel has 3 models

Gas engines --- water temp gauge starts at 130 goes up in 10 steps to 265 - yellow alarm at 220 degress red alarm at 250 degrees

Cat Diesels ----  water temp guage starts at 110 goes up in 10 steps to 245 - yellow alarm at 200 degrees red alarm at 230 degrees

Detroit 2cycle- water temp guage starts at 100 goes up in 10 steps to 235 - yellow alarm at 190 degrees red alarm at 220 degrees

all temp sensors are small "solid state devices" that strap to the engine (thermostat housing - A/T output fluid line etc) -

I like that fact that the water temp is really (ENGINE TEMP) cause if you lose your coolant older styyle sensor WILL NOT REACT FAST enough if they're NOT IN A LIQUID

Only the oil pressure sender is regular style sender 

[rv_safetyman]

Thanks Pete.  I am glad that they adjusted to the market.  Seemed to be really nice folks with a good idea.

I have had terrible luck trying to get an good indication of ENGINE temperature (not compartment temperature) by attaching my sensors to locations on the engine.  I have tried at the thermostat housing on both diesel and gas engines and the reading is always significantly lower than the coolant temperature.  I had thought that I was getting cooling from the ambient air.  I tried adding significant insulation including quite a ways down the sensor wire.  I was going to install the sensor in a fitting that screwed into the water jacket, but never got that done.

It sounds like you are getting good correlation.  Would it be possible for you to either describe the mounting, or post a picture?

Thanks

Jim

[RTS/Daytona]

The Digi-panel sensor (a LM34 Transitor - 10mv/*f) are mounted on a thin piece of copper with a hole in it (see attached links)

Just put the sensor UNDER THE WASHER on a thermostat housing bolt  - Works for me - tracks well (a little slower) to my other gauge and my Pro-link

here's what the sensor looks like
http://users.sfo.com/~eagle/chassis.html#digi

this is the heart of the sensor
http://instruct1.cit.cornell.edu/Courses/ee476/labs/s2004/LM34.PDF

Here's the DIGI-PANEL info
Digi-Devices - Art Woodall
23815 Avenue 26, Chowchilla, CA 93610
Mailing: P. O. Box 178, Madera, CA 93639
Ph: (559) 665-1546, E-mail: digidevices@peoplepc.com

I have no vested interest with this company - just have used his device for years



Small note - When I found the RTS I wanted - it was in California (I live in Daytona Florida) - I found a cheap roundtrip ticket (just in case)

Fat - Dumb & crazy as I've always been - I flew out (with a small suitcase of tools & my Digi-panel) - had the bus inspected - paid for the bus - got a temp plate
pulled it into a parking lot and it took less than 15 minutes to install the DIGI-Panel (I did run the wires out the engine compartment and into a window and up front - plugged into 12 volts up on the dash) and left for Florida - I did this cause the RTS has NO ENGINE TEMP / NO OIL PRESSUE / NO TRANNY TEMP gauges

And then drove 2000 miles back to Florida in JUNE - thru the desert at over 100 degrees outside temp - in 5 days (having NEVER DRIVEN A BUS or WORKED ON A DIESEL ENGINE)

I wouldn't have tried it without know my engine temps and pressures

Pete RTS/Daytona

[BG6]

I sure would like to know what all is available out there that I can install to protect my 8V92T investment? 

Wire an intercom in the engine bay, then put in a seat for your mother-in-law to ride back there and keep an eye on things.

[JohnEd]

A rule of thumb for military equip was that the more stuff you put into a piece of electronic equipment the "shorter" the Mean Time Between Failures" became.  There is also a law of diminishing returns.  From my experience I don't think Jack has even come close.....really nice.

I would even add:  I used a engine water temp sender mounted in the drain plug to monitor my differential oil temp.  I have a marked "diff"/"water" and I use the same gauge to monitor both temps.  I have no alarm for the diff.  I once confirmed that I had a brake dragging by noting that the diff temp was "up" and my vac (gas engine) was a tad low.  Brake pedal was adjusted to ALMOST return far enuf to completely release the rear brakes.  I paid that shop a lot of money to do that to me, I might add.

I also walk around the coach and "shoot" the temps of the hubs.  Only when I am stopped though.  I sure have found a lot of uses for that HF temp gun and the last was air infiltration points.

2 centavos,

John

[David Anderson]

This thread got me wondering, so I went out to the coach and put 12v power to the alarmastat and by golly the circuit didn't engage.  After tinkering with the wiring I found a loose connection and fixed it.  BUT, I now installed a relay and power the coil with the starter button wire that tests the
"HOT ENGINE" circuit every time the starter is engaged.   I had to use a relay so if the alarmastat did go off and pick up its power from the common terminal I didn't want the circuit to send 12v backward to the  starter relay. 

I can now see the circuit engage every time I start the bus.  The "low oil" and "low water" alarm chimes at each crank sequence, so the "Hot Engine" circuit should, also.  This board is great. 

David

[rv_safetyman]

As David said, this has been a good thread.

Pete, the link you show on the coolant connection talks about having failures at the sensor and soldering to repair.  At first I thought they were saying that the sensor was soldered to the copper tab.  That did not make any sense.  As I look at it again, I think they are talking about soldering the thermistor(?) to the wire to repair a connection.  Assuming that is correct, how do they insulate the sensor from the tab?  When I was playing with my unit I was looking at a thermally conductive epoxy.  Again, never got that far.

As a side note, because of the importance of our sensor wiring, our micro processor is programmed to check for open and shorts in the sensor wiring.  Even though it should be obvious on the monitor, we wanted to make sure that the owner was advised that the wiring was compromised using an audible alarm.

David, was the alarmastat part of the Eagle system?  We have sister buses and I don't recall seeing one.

Jim

Jim

[RTS/Daytona]

Jim

I only used the GMC Motorhome  (sensor repair photo) to give you an idea of what the sensor looks like.

Why don't you give Art a call - He's a nice guy and I'll sure he'll be able to amswer your questions

Pete RTS/Daytona

[David Anderson]

David, was the alarmastat part of the Eagle system?  We have sister buses and I don't recall seeing one.

Jim

Jim

Yes, it should have been on the street side bank adjacent that thermostat of your old 6v92 and wired into the auto shutdown system.  It has a 12v hot common, a N.O. wire for the temp below 210 (closes at 210), a N.C. wire to send power to the oil pressure switch when below 210.  The N.O. wire is 79 in the manual and illuminates the "Hot Engine" light and begins the auto shutdown sequence.  I would think all the Houston Metros had this system. 

This is an important warning light and buzzer.  When I had my bottom radiator hose come loose and lost all my water the alarmastat screemed at me and I had the engine turned off within 30 seconds.  No damage was done.  That was 6 years ago and I've never thought about it since until I read this thread.  Now I will see it every time I start the coach. 

David

[johns4104s]

Pete,

I called Art and discussed the system. On the standard unit there are a total of 4 digital censors. Coolant on the engine, temp of the transmission, oil and battery condition. I would like to have 2 engine temperaturesArt said I can forgo the battery sensor and use it for the 2ND engine censor. One for each bank on the 8v92. I dont know much about the 8v92 or where I would put them? Does anyone know if I need one for each bank? The engine sensor is attached to one of the bolts that hold the thermostat in. The sensor has a copper strip  with a hole in it that slides over one of the bolts. The readings sent to the front monitor is produced by the metal that the sensor is bolted to. When you loose water the Thermostat heats up and this heat transfers though the housing and though the bolt. I wonder if this is fast enough to alert you before any damage occurs?
Art said the alarm was good and loud.
Pete I want to do whatever it takes to feel good about what is happening in the engine/tranny compartment.

John

[Mark Scott]

Jack, whose gauges (manufacturer) are you using on your dash? Thanks, Mark

[NJT 5573]

I trust my DDEC just fine, it always thinks some damn thing is wrong.

[JackConrad]

Jack, whose gauges (manufacturer) are you using on your dash? Thanks, Mark

I get my gauges from Precision Speedometer in Phoenix, AZ. The gauges are manufactured by Datcon.  I feel the prices are reasonable and their customer service/tech support is superb.  http://www.precisionspeed.com/    Jack

[Len Silva]

I have wondered about the idea of a "coolant pressure alarm".  Of course, it would be in alarm during initial warm up, but might be the first indication of a major coolant leak.  What'cha think??