Yup. I have never been above horizontal, even crawling long hills at low speed. Usually 1 to 2 needles below.
93-97 Coolant Temperature Gauge Modification (9 Viewers)
- Thread starter RavenTai
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Yup. I have never been above horizontal, even crawling long hills at low speed. Usually 1 to 2 needles below.
semlin
curmudgeon
it would work mechanically but iirc there is a screw mounting hole out of place.
- Thread starter
- #203
What Semlin said,
See pic below, stock 93 on the left, modified 97 on the right, like a lot of other year changes 93 and 94 are the same, and 95 through 97 are the same.
Notice the placement of the bottom standoff and screw, The screws are also the electrical connection, (In this case ignition switched 12v + supply) it would not be to bad to move it on the gauge PCB, it is already pre-drilled you woudl just have to make contact, but the circuit board of the cluster is a different story, it could probably be done by a good tech, possibly deleting that screw and making a wired connection but I think it would be a lot easier to just modify your 97 gauge.
Please ignore the poorly executed bends on the resistor it was the first run on the test bed gauge,
Anyone have any extra resistors? I'd be willing to pay for parts and shipping. I'll order from the source if I have to but I hate paying inflated shipping costs.
Where are you?wearsabrowncoat said:
Yeh, they kind of get you of stick it to you on the shipping. I sold my extras to Mr. Bryan. It cost about a dollar to ship them to someone. If you can get a couple of people to buy with you, you can dilute that shipping charge some.
Rookie2
- Thread starter
- #207
Yes the shipping is high for just 2 resistors, although it is nothing to really complain about considering the value of the mod, the shipping is not much more to ship 20 resistors so we are stuck in the scale that the company works with. They get you for small orders.
Thanks for the replies. I found a member in WA to send me some.
NaterGator
On Gilligan's Island
Hmm... I was going to tear into this tomorrow so I would have a more sensitive gauge before I take my car (and parents) to Atlanta/NC on Thurs, but now reading that "red-hot" is ~217°F after the mod... I'm thinking I won't since I don't want the parents to freak out and pull over if things start to creep up but not to the point of danger.
Maybe it will be worthwhile for me to try and more accurately model the circuit -> needle position correlation... eventually I would love to script up something where different circuits can be "built" and a virtual gauge can be toyed with. I'm fairly confident I have the necessary math/calculus background to accurately describe all said circuits and the needle position, I suppose it would come down to the necessity of a predictable and fairly accurate needle solution from Toyota (read: no varying resistive-spring tensioning on the needle) as well as decent measurements of the components to describe everything mathematically. It sounds to me like to 100+150 combo is a little too numb for a hot climate like Florida and the 50+110 combo is a little to sensitive. Hrm hrm hrm... decisions decisions.
Maybe it will be worthwhile for me to try and more accurately model the circuit -> needle position correlation... eventually I would love to script up something where different circuits can be "built" and a virtual gauge can be toyed with. I'm fairly confident I have the necessary math/calculus background to accurately describe all said circuits and the needle position, I suppose it would come down to the necessity of a predictable and fairly accurate needle solution from Toyota (read: no varying resistive-spring tensioning on the needle) as well as decent measurements of the components to describe everything mathematically. It sounds to me like to 100+150 combo is a little too numb for a hot climate like Florida and the 50+110 combo is a little to sensitive. Hrm hrm hrm... decisions decisions.
- Thread starter
- #210
Nator, I run around Gainesville often when I am down here. It is the closest city with big box stores, Quite happy with the 50/110, if your cooling system is running correctly it is stay around the middle even with this "sensitive" version of the mod in FL.
If you want to come up with a model let me know. I tried for a wile, I can get close with ohm’s law but there was always a variance when I applied it to the gauge.
If you can work with thevenin equivalents you will have a leg up on me. The circuit is somewhat like a whetstone bridge, but two of the resistors are actually inductors of the needle motor, I think that is some of the variance, there is also something in the motor that brings the needle to full cold when the power is removed, not sure if this is a spring or small magnet.
I heard recently that your whacko city government wants to put round about on tower road? That is the only decently moving road in the whole congested city and they want to slow it down.
If you want to come up with a model let me know. I tried for a wile, I can get close with ohm’s law but there was always a variance when I applied it to the gauge.
If you can work with thevenin equivalents you will have a leg up on me. The circuit is somewhat like a whetstone bridge, but two of the resistors are actually inductors of the needle motor, I think that is some of the variance, there is also something in the motor that brings the needle to full cold when the power is removed, not sure if this is a spring or small magnet.
I heard recently that your whacko city government wants to put round about on tower road? That is the only decently moving road in the whole congested city and they want to slow it down.
NaterGator
On Gilligan's Island
I suspect there are some obfuscated dampening and oscillatory properties of this circuit which make them unpredictable.
Thevenin equivalents are not all that bad... it's no different than general relativity and the idea that gravity and accelerated motion are indistinguishable. I will admit though that Thevenin equivs are not quite so straight forward until you do some "hands on" with them.
I think the biggest problem with modeling may be if the needle is resisted by a spring. I suspect the spring will probably act progressive and I doubt I'll have equipment sensitive enough to accurately describe the spring's effect on the needle.
Our whacko city Government can't surprise me anymore. They just approved 8 story commercial buildings on the corner of Univ. and 13th where they have already sold 200% more living space than they have provided parking spots, and now in the same area 2 more apt buildings are finishing with zero parking provisions and then University Corners will go up... it's just plain stupid, but it's G-Ville.
Thevenin equivalents are not all that bad... it's no different than general relativity and the idea that gravity and accelerated motion are indistinguishable. I will admit though that Thevenin equivs are not quite so straight forward until you do some "hands on" with them.
I think the biggest problem with modeling may be if the needle is resisted by a spring. I suspect the spring will probably act progressive and I doubt I'll have equipment sensitive enough to accurately describe the spring's effect on the needle.
Our whacko city Government can't surprise me anymore. They just approved 8 story commercial buildings on the corner of Univ. and 13th where they have already sold 200% more living space than they have provided parking spots, and now in the same area 2 more apt buildings are finishing with zero parking provisions and then University Corners will go up... it's just plain stupid, but it's G-Ville.
- Thread starter
- #212
If you say so, I found the formula online and dropped in the numbers I thought in the right spot but all I got out was garbage, I did not know enough about it to figre out what I was doing wrong, for me in the end it was just easier to get it close on paper and then tweak it via trial and error. I had a spare gauge and a heat source, digital thermometer & power supply all set up in a test bed.
This would be great. The problems I was finding was that the resistor and temperature values for the temp sensor when measured alone didn't quite match up with the temperatures and resistor values that were determined by Raven's test. I used the test values instead and was able to get a mostly consistent model. Unfortunately my notes are like my methods, jumbled thoughts and in storage (literally in storage).
Where do you want the extremes? I did run some other resistors for a while that might give you more what you want. I posted some of the results in the development thread.
https://forum.ih8mud.com/showthread.php?t=53142&page=10
NaterGator
On Gilligan's Island
Well I did the mod today with what I had on hand while my oil drained which was the 50+110 combo and it is working so far from my limited trials. It looks like the needle rests pretty standardly horizontal and does climb slightly with low speed (ie low airflow) usage, but it has been cooler here as well.
I'll let it rest until I have a reason to muck with it, and if I do I'll probably do so over the summer and dig deeper into the construction.
I'll let it rest until I have a reason to muck with it, and if I do I'll probably do so over the summer and dig deeper into the construction.
RT, great job on the R&D for this. I did it last week and didn't have too many problems. Couple of notes though, the 93-94 dash comes apart a little different as you have noted; the piece that wraps over the steering column is the same piece that holds all the temp controls and various buttons, so you have to unplug all of those as well.
It is a great time to put in the CDL switch though, and also rearrange any of the buttons that you would like in different places. The key to getting that piece off is removing the screw by the hand throttle and then all five of the screws behind the ash tray.(this may not be "needed" but it makes it easier to move that big expensive piece of plastic around. Two screws pointing outboard diagonally on either side, one pointing up diagonally at the center, and two pointing straight up just under the lip. It also isn't neccesary to remove the steering column cover, I had most everything back together when I noticed that the odometer knob wasn't sticking out through the hole, so I had to pull it back apart.
Also, the 93-94 board doesn't seem to require drilling out the holes where the diode was.
X2 on the solder braid sucking, and one last thing:
I tried to be cool and bend the resistor over like your post shows, but I put mine on the inside, and when I pushed on it, the metal strip separated from the board, and I had to superglue it back on. So, be careful with the circuit board, and don't bother making it look pretty, not too many people will look in there.
Thanks again!
Dan
It is a great time to put in the CDL switch though, and also rearrange any of the buttons that you would like in different places. The key to getting that piece off is removing the screw by the hand throttle and then all five of the screws behind the ash tray.(this may not be "needed" but it makes it easier to move that big expensive piece of plastic around. Two screws pointing outboard diagonally on either side, one pointing up diagonally at the center, and two pointing straight up just under the lip. It also isn't neccesary to remove the steering column cover, I had most everything back together when I noticed that the odometer knob wasn't sticking out through the hole, so I had to pull it back apart.
Also, the 93-94 board doesn't seem to require drilling out the holes where the diode was.
X2 on the solder braid sucking, and one last thing:
I tried to be cool and bend the resistor over like your post shows, but I put mine on the inside, and when I pushed on it, the metal strip separated from the board, and I had to superglue it back on. So, be careful with the circuit board, and don't bother making it look pretty, not too many people will look in there.
Thanks again!
Dan
semlin
curmudgeon
dan, let me know where your needle sits. mine sits somewhere above the half way point after hill climbs or on sustained highway driving. i'd like to know if it is a 93-94 trait.
Mine seems to sit just below half for the most part, but climbs to just above half only on hills. I haven't run it in hot weather yet, or with AC in town, so time will tell. My stock fan clutch works really well and the coolant is fresh, so that may be part of it. I drove it about 300 miles last week, bur after reading this thread, I have come to ignore the thing, so I didn't take notice of what it was doing very often. I'll pay attention more this week and post back with results.
- Thread starter
- #218
Thanks for posting up dash tips for the 93/94 trucks, I figured it would be different but did not have one around to add any notes.
you were suppose to bend the resistor legs before you put it in
you were suppose to bend the resistor legs before you put it in
- Thread starter
- #220
got asked this via PM figured some others might the same question so posting it here
m said:
