93-97 Coolant Temperature Gauge Modification (3 Viewers)

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Send me a pm with your shipping info
 
Send me a pm with your shipping info

I have tried here in Spain and in the UK to get the resistors and have had no luck at all, I have tried all the usual outlets, Maplin, Farnell, RS components ect and still no good, can I pm you with my address details in Spain and send you some money via whatever method you suggest so you can post me a set?

Happy New Year to you and all!:cheers:

Thanks in advance

regards

Dave
 
I have same problems. Can anybody mail me a set of 110 an 50 ohm (3W, 1%) resistors to get this mod done ? I live in Poland, will pay in any preferred way, but I need this parts ASAP, as I am going on a trip to Africa in a month time.
 
Another one to add to the list

Hi all, I have just come in from the yard after completing the gauge modification. Everything went as per the 'instruction manual' RT compiled and I am very impressed. I started the engine up and kept an eye on the gauge and after 3/4 minutes...........nothing! But I know diesels take a little longer to warm up incomparison to their petrol brethren, I also recall reading that the original set up came up to the centre quite quickly so waited a further 3/4 minutes and bingo! The needle started to come up to the first mark on the gauge, so I shut it down and boltd everything together. I am an avid gauge reader and have various photo's of the 'normal' position of the temp gauge needle (sad right?) for comparision as a 'before and after' check.

At the moment I am staying at a friends house and this involves travelling a short distance tommorow morning (40 ish miles there and back) to do a little job and I will report back tommorow evening on the outcome, but it all looks good so far.

Probably one of the cheapest 'bang for buck' mods you can do and it might just save you a fortune if something is not good under the bonnet?

Thanks Raventai for your time and efforts along with everyone else who has contributed, and last but not least an extra thank you for azTony for getting the resistors over to me here in Spain as they are as rare as hens teeth here.

:cheers:

regards

Dave
 
Diesel? I will be interested to know the outcome.
 
Diesel? I will be interested to know the outcome.

The outcome was better than I expected RT,

First some information that may prove useful:

Cooling system flushed early last year, new radiator, not OEM but the same design aluminium with plastic header tanks, Green coolant/antifreeze 50/50 mix, this is one of three mixes that I have seen you can buy in here, this is pretty much how you buy you antifreeze, already mixed with distilled water ect so it is good to go.

No other cooling system mods

Markings on gauge seen when removed are: Front 769133-051 rear on PCB 769902-961

Usual position for needle is dead centre of 'normal' range and would be there within 3/4 minutes of driving, it would then not move up or down regardless of outside temperature and load.

As it can be very difficult to explain needle positions I tried to put little arrows on the pic using 'Word' but they would not show up on the uploaded picture so I will try to explain the range of movement.

From cold this morning which was a chilly 7 degrees C in the hills the needle was over the 'C' as per the picture below. A 3 to 4 minute drive down a rough track to the highway brought the needle on to the white line above the 'C'. I joined the highway and was straight up to about 60 MPH for 4/5 minutes and the indicator was as near as damn it 1 and 1/2needle widths below the centre of the gauge. Next we come to a steady 500 metre drop to sea level, I always tend to knock the gearbox into neutral and coast down, and within a few hundred yards the needle had dropped half a needle width, prior to the mod the needle would not move at all.

As the road levelled out and I was back on the power the needle climbed back to being roughly one and a half needle widths below centre. This where it stayed during some running around the town, (20 degrees C at the coast), whilst I was near a friends workshop I popped in and grabbed a laser temperature indicator gun, with it pointed at the cylinder head it indicated 80 degrees C, this varied by 1 or 2 degrees depending where you pointed the laser beam along the length of the engine, I had opened the bonnet the moment I stopped and the readings were taken within a minute so no heat soak to alter readings.

A few moments later I had a call from a friend, two of his dogs had ingested some poisonous caterpillars, this can be a life threatening issue here in Spain and they needed to be treated at a vets without delay. This resulted in me driving the car pretty much flat out and back up that 500 metre climb from earlier, during the climb the needle hit dead centre where it would be during normal driving, as the road levelled out I went straight through a speed trap, by the time the cops had pulled out of the slip road I was off the road and into the campo where my friends house was, if they have my number I'm toast anyway, a forced and slower more sensible speed was needed to negotiate the track up the hill this resulted in the gauge again dropping to it's earlier one and a half needle widths below centre, the gauge, this proves that even when the engine is still relatively cool the gauge shows it as being dead centre and at working temperature even when it is not. The dogs were loaded in and then a very hard and fast drive to the vet, to be honest at this time I was not looking at the gauge as this had become of secondary importance as I was zipping around the traffic in town. On the return home (without the dogs) the gauge again
returned to it's now new home, 1 1/2 needle widths below centre. Based on how far the needle moved when driving hard and where it sits when driving 'normally' should give me a little more warning if something goes t*ts up under the bonnet. If I have left out any pertinent information please let me know.

The dogs on the other hand are still in the vets sedated and at the moment not looking very well.

Thanks again for this mod,

regards

Dave
Gauge resized.jpg
 
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sounds good, that sounds very similar to the behavior of a modified gauge in a petrol cruiser

British ex-pat living in the mountains close to the ocean in Spain with a diesel land cruiser? somebody is living it up :cheers:
 
I offered the parts numbers so perhaps they can be used for comparison as they are from a UK spec VX diesel.

I have been out and about again this evening and the needle is still sitting a needle and a half below centre which suits me fine.

British ex-pat living in the mountains close to the ocean in Spain with a diesel land cruiser? somebody is living it up :cheers:

Oh no, it is a little to cold for me to live up here.......I have to suffer living at least 80 yards from the sea and it is horrible :D

I am looking after a friends house at the moment while he is away which is cool and I enjoy it, it is all solar panels and wind power with a back up genny which is not needed that often, it is quite peaceful if a little solitary but I'm happy, I am sure there is a bit of gypsy in me somewhere?

And in case anyone is interested one dog seems to be ok, and the other depends on the condition of her tongue as it was damaged quite bad.

regards

Dave
 
I just installed the 110/50 ohm resisters, but I may have a potential problem. After they are soldered on the 110 ohm one reads only 74 ohms, and that is on the wire not on the solder joints, which coincidentally are the same reading. The 50 ohm one is reading 43 ohms. Is this normal for the resistance to somehow drop after soldering them on?

I removed the 110 ohm one to check it, and it read 110 ohms, so I put it back in and got 74 ohms again. What's going on?
 
You are reading the equivalent resistance of the circuit at that point.

Once you solder them, they become a part of the circuit network, and when you test two points electricity flows in all possible paths between the two points to varying degrees.

You can learn more about the basic principle here: Thévenin's theorem - Wikipedia, the free encyclopedia

Alternatively, you may just accept that it is normal and button everything back up.
 
Yes checking resistance of the resistors in circuit is misleading, you are observing parallel resistance, the more resistors you add in parallel the lower the circuits overall resistance, electricity seeks all paths and this one being a bridge there are many paths in this circuit. what you are looking for with the meter is low resistance across the solder joints.
 
Great, thanks guys. The resistance of the connections was good, so I am good to go.
 
Great, thanks guys. The resistance of the connections was good, so I am good to go.

Another one on the list RT, now if youcan sort out the big end bearing problems on the diesels for perhaps $1.50? :D

The temps are starting to climb here now, it will be interesting to see what the gauge reads when outside temps are around the 45 degrees C :eek:


regards

Dave
 
Has anyone recently tested how accurate this is on the 93/94's? The first post said it's within a few degrees of the scale listed.

The reason I ask is that I just finished a HG job last night and took it out for a spin. After a 10 minute drive up a steep hill about 1/2 mile from home my temps skyrocketed to about one needle width below the red line. I quickly drove home and the needle didn't rise any more and it never got into the red, it just sat there one needle width below the red. It was only a couple of minutes, and I had the heater on full blast but blowing cold air which I later realized was due to lack of coolant. It turns out that a rad hose popped off and I was about 3.5 gallons low on water so almost bone dry. I filled it up again with tap water and the temps dropped down to the mid point then eventually to cold levels. Being that low on coolant, even only for a few minutes would make me believe that the engine was much hotter than 217 on the scale listed below.


Pegged hot 244°
Top of red is 227°
Bottom of red 217°
Center is approximately 189°
Cold line is 160°
Pegged cold 150°

Any thoughts other than I'm a complete bone head for not double checking the DS rad hose before driving it?

I'm sure the fairly rapid cooling of the motor with cold water wasn't good for it either. :bang: But it seems like the hot radiator pre-warmed the majority of the water or at least that's what I'm telling myself to make me feel better about the situation.
 
If you completely loose coolant the gauge is not accurate.


The sender is reading water temp in the head near the water outlet, as long as there is water present this is a good relative indication of cylinder head temperature but with just air contact reading will be very slow to respond. If you only had 1/2 gallon of coolant driven for more than 30 seconds I garontee your head was overheated.
 
Has anyone recently tested how accurate this is on the 93/94's? The first post said it's within a few degrees of the scale listed.

The reason I ask is that I just finished a HG job last night and took it out for a spin. After a 10 minute drive up a steep hill about 1/2 mile from home my temps skyrocketed to about one needle width below the red line. I quickly drove home and the needle didn't rise any more and it never got into the red, it just sat there one needle width below the red. It was only a couple of minutes, and I had the heater on full blast but blowing cold air which I later realized was due to lack of coolant. It turns out that a rad hose popped off and I was about 3.5 gallons low on water so almost bone dry. I filled it up again with tap water and the temps dropped down to the mid point then eventually to cold levels. Being that low on coolant, even only for a few minutes would make me believe that the engine was much hotter than 217 on the scale listed below.


Pegged hot 244°
Top of red is 227°
Bottom of red 217°
Center is approximately 189°
Cold line is 160°
Pegged cold 150°

Any thoughts other than I'm a complete bone head for not double checking the DS rad hose before driving it?

I'm sure the fairly rapid cooling of the motor with cold water wasn't good for it either. :bang: But it seems like the hot radiator pre-warmed the majority of the water or at least that's what I'm telling myself to make me feel better about the situation.

based on my 93 gauge indications i would say the earlier gauges when modded will get to red at lower temps not higher ones. i have had my 93 pretty close to the red on nasty long hill climbs on hot days.

i think maybe you got lucky in that you lost coolant just before your engine came off load and your block had not yet warmed up enough to cook itself.
 
If you completely loose coolant the gauge is not accurate.


The sender is reading water temp in the head near the water outlet, as long as there is water present this is a good relative indication of cylinder head temperature but with just air contact reading will be very slow to respond. If you only had 1/2 gallon of coolant driven for more than 30 seconds I garontee your head was overheated.

This is what I was afraid of. I'll keep an eye out for impending HG doom. I can't tell you how mad I am at myself.:mad:
 
Keep an eye on it and see what happens. Maybe the head was not yet up to temp yet when the loss happened? All you can do is drive and watch.
 
Keep an eye on it and see what happens. Maybe the head was not yet up to temp yet when the loss happened? All you can do is drive and watch.

That's the plan. Everything happened really quickly and I had the motor off within minutes and the temp never got into the red. (but like you said the sensor isn't accurate w/o coolant)

I'm hoping that with a freshly milled head and updated HG that everything will be fine. I'll keep my fingers crossed. If it does blow, at least everything was put together with antiseize and it should go a lot quicker the second time.
 

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