93-97 Coolant Temperature Gauge Modification

[RavenTai]

You got a "Conehead" (avionics tech) to do it, good move, those guys know their stuff.

When the outside temps are in the 40's mine runs slightly low just like the next to last pic, that slight uptick when stopped at a light is also very typical, all good signs that all is as it should be with the gauge,

I am sorry you had trouble with it but glad you finally got a good finish, thanks for reporting back

in the first picture, R1 (110 ohm) position closest solder point it does not appear that the solder is climbing up the resistors wire, that can be a indication of a cold joint could have been your problem, or was that taken in the middle of the process? otherwise they do look good at least from what can be seen remotely.

You say your iron is not hot enough? is that a small wattage iron? I have 2 Weller irons, one pencil style in 40 watt that I used for doing this mod, same brand but not the same model as the one you have pictured, the other an ancient but hearty pistol grip 100/140 Watt that I use for soldering wires.

This being PCB work the wattage needs should not be that high,

Is there something I can add to the instructions that may help steer someone else from these kind of problems?

 

[Beowulf]

Noel,
Your truck only has 57,000 miles? ! ? ? ? !

Lucky dog.

-B-

 

[4x4CPOSEADOG]

Noel,
Your truck only has 57,000 miles? ! ? ? ? !

Lucky dog.

-B-

Siirrr Yes Suuuurrrrrrr! That's the original miles, garage kept, babied, and TLC'ed. The is jealous about my rig because I spent a lot of time in the garage.

 

[RavenTai]

57,000 miles

-B-

Is that thing even broke in yet?

 

[4x4CPOSEADOG]

You got a "Conehead" (avionics tech) to do it, good move, those guys know their stuff.

When the outside temps are in the 40's mine runs slightly low just like the next to last pic, that slight uptick when stopped at a light is also very typical, all good signs that all is as it should be with the gauge,

I am sorry you had trouble with it but glad you finally got a good finish, thanks for reporting back

in the first picture, R1 (110 ohm) position closest solder point it does not appear that the solder is climbing up the resistors wire, that can be a indication of a cold joint could have been your problem, or was that taken in the middle of the process? otherwise they do look good at least from what can be seen remotely.

You say your iron is not hot enough? is that a small wattage iron? I have 2 Weller irons, one pencil style in 40 watt that I used for doing this mod, same brand but not the same model as the one you have pictured, the other an ancient but hearty pistol grip 100/140 Watt that I use for soldering wires.

This being PCB work the wattage needs should not be that high,

Is there something I can add to the instructions that may help steer someone else from these kind of problems?

RT, those coneheads did a great job in resoldering them resistors. That's mostly what they do on a daily basis, soldering.

Now, I know my gauge really works as you mentioned in your second paragraph.

I know I have to report back ASAP to let every one knows the progress on what's going with the gauge so we can inform others on what went wrong. No need for apology but I rather would like to THANK YOU for this amazing modification and your great and massive technical contributions to MUD, especially in the 80 Series Tech/Forum.

The first picture was taken in the middle of the process. I took that picture to illustrate the position the R1 resistor for my record.

The Weller pencil type soldering iron that was used is probably around 15 to 30 watt. It can melt the solder but quickly turns cold because whenever I pulled it out off of the solder joints, the soldering wire still sticking to the tip of the iron.

The only thing I can think of to add to the instructions to help someone to steer from these kind of problems are:

1. Soldering Iron should be at least 40 Watts to maybe around 60 Watts or if money is not an object I would get this nice soldering station from Radio Shack Digital Soldering Station - RadioShack.com

2. Room temperature for soldering should be at least 65*F for the solder to slowly cool off instead of an immediate cool off due to air temp at 55* and below.

3. Make sure to clean the resistor wires with alcohol pad to remove grease, finger prints, and dirt prior to install/solder on the board. This case the solder will quickly clings to the wires the minute it melts.

4. Do not use flux in paste form but use the one in liquid form. Paste tends to get hard and it is harder to clean even with acid brush and alcohol.

5. Always take the negative battery cable off the battery when working on electrical/electronic equipment specially the four connectors in the back of the instrument panel to prevent grounding of sensitive connecting pins. This is one of the thought that came to me when the temp gauge needle did not move, I thought I fried something in the back of the panel. Thanks God, I did not fried any wires back there.

So far that is all I can think of and please pardon me if they were already covered in the previous posts.

Thank you for this cool mod.

Is that thing even broke in yet?

Not broke in yet, matter of fact the hymen :whoops:is still intact. Still a cherry!

 

[BenMara]

ouch look at the price at radio shack
i like this one better
Circuit Specialists Inc. - Digital Display Soldering Station (CSI-STATION2A)

 

[wildman326]

Great mod! Just did it and replaced the driver light also. Everything works like a champ!

Thanks for this RavenTai!

 

[landshark1]

RT, thank you very much for all of the time you put into this mod. I did it over the weekend, and it works like a champ. Very cool, and it only cost me a few bucks and a few hours. Very much appreciated!!!

Chris

 

[BenMara]

ok did the resistor mod. at idle and around town its about half way, a lil below or above. now when i get goin on the highway about 60-75 it creeps up about 1-2 widths before red.
Should i be worried?

 

[RavenTai]

I assume your temps were similar to ours (65 -70) yes that seams high, watch it and see if it goes higher.

 

[citadel]

add me to the list.. completed the mod today.. the gauge rises a lot slower after cold start up and has been settling in at the half way point... it is well over 90 here in Texas so I will take the mid point position of the gauge as a good sign....

 

[landtank]

ok did the resistor mod. at idle and around town its about half way, a lil below or above. now when i get goin on the highway about 60-75 it creeps up about 1-2 widths before red.
Should i be worried?

Yes you should. I'd look into your fan clutch.

 

[80t0ylc]

Thanks RT, for this very helpful thread and all the research and effort by you and all who contributed. Cost was minimal (little over $3) thanks to Davework who organized a buy and delivery. I'm now very familiar with the "black hole" behind the steering wheel. Being as mine is a '94, I combined your dash dis assembly with my FSM and it worked out ok. FSM called out to remove heater duct #2, combination switch & turn signal bracket. None of which was necessary to remove. My steering column cover is in such poor shape, it was the biggest challenge & source of much frustration.

I'd suggest using a pair of hemostats (they're like a locking pair of needle nose pliers) for bending the resistor leads and as a heat sinc while soldering. They'll help you be able to custom bend the resistor leads exactly as you want. Also, the use of resin core solder will clean the joints as you solder for better results. Do not use acid core - that's for making plumbing joints.

I couldn't find the "extra credit" characters on my gauge plus I couldn't read the one I was supposed to add, so that was a wash. I wished I'd had more artist skills so I could put the new temps at the right spots on the face of the gauge. Maybe a decal could be fabbed by someone with the right connections, for future newbies digging in to it.

Thanks again to all who helped!!!

 

[RavenTai]

nice work guys,

there was some talk about a decal for a while, the repeatability of the mod is decent but not perfect bringing the precision of any markings into question

 

[Cruiserdrew]

Yeah, but Raven you deserve MAJOR props for this. I love being able to know at a glance what's going on. Once done, it totally changes the way you look at your temp gauge. It is helpful to calibrate with a scan gauge, but once done it's amazingly repeatable.

 

[JerseyCruiser]

I have a 93 with the 100/150 resistor combo and I need to know what temperature I'm at with reference to the needle position. The only temperature chart I see is for the 50/110 on a 95-97 and being that that a 93 gauge will read slightly higher than a 95-97 I need someone with a 93-94 to chime in. One last thing at what temperature would one stop and turn off the vehicle to prevent any damage I would take a guess at 220?

Thanks
George

 

[RavenTai]

I could be wrong but as far as i know only the standard mod (110/50) has had any thorough testing for temperature.

 

[RavenTai]

Once done, it totally changes the way you look at your temp gauge. It is helpful to calibrate with a scan gauge, but once done it's amazingly repeatable.

you are right and I should clarify, I have never seen a particular gauge not show repeatability compared to itself, but of the three I have put through testing (one 96. one 97 one a 93) there was a difference of a few degrees,

Weather there is a difference between years or is there just a variation from gauge to gauge is unknown.

 

[JerseyCruiser]

I could be wrong but as far as i know only the standard mod (110/50) has had any thorough testing for temperature.

You are correct. Did you ever find out what the difference is between the 93-94/ 95-97 gauges? Some in this thread said the 93-94 runs a bit hotter just wondering if its just the engine setup or is the gauge slightly different in its readings.

George

 

[RavenTai]

I found a difference between one particular 93 vs a 96 and a 97, this was the gauge isolated by itself in the test bed not attached to a vehicle, it is worth noting this particular 93 gauge did make a trip from BC Canada to Georgia back to BC and back to GA again before testing.

I cannot say weather this few degree difference was just that particular gauge or was it a trend that would apply to all 93/94 gauges. was it my error is setting up the test bed? with a sampling of just one none of this can be answered. it is just a few degree's for the most part not a problem.