Engine Temperature Sensor

[Dan M]

 

See, that is where the debate gets fuzzy. You say that the brass is insulating the actual sensor. In my experience, brass is a horrible insulator for heat. It actually conducts heat better then air, which is what you are "replacing" the brass with. I have yet to see anyone post any actual measured data that supports the theory that removing the brass and adding air increases the response time or the accuracy of the sensor. Or any evidence that the stock set up is "a very, very slow sensor". So then it comes down to opinion and belief, and that does not make for something worth debating.

 

 

It was indeed tested. Side by side with an air temp sensor. Findings were posted in the last thread inbetween the bickering. The brass unit is as much as two minutes behind the exposed thermistor sensor.

 

Anyway, this has all been talked about before. Probably time to put it to bed.

I'm glad all those who have done it have had good results.

[gstallons]

It was indeed tested. Side by side with an air temp sensor. Findings were posted in the last thread inbetween the bickering. The brass unit is as much as two minutes behind the exposed thermistor sensor.

 

Anyway, this has all been talked about before. Probably time to put it to bed.

I'm glad all those who have done it have had good results.

 

 

I like the new avatar !

[docc]

The observations of empirical changes by an experienced rider are not theoretical. Otherwise, winning race teams would not have their riders giving feedback to the technical people.

 

Certainly, my experience or observational abilities could be discounted. Yet, I'd say I know this bike pretty well, and that I've "tested" the three set-ups adequately to make valid observations.

 

Please note: this is not a continuation of the old thread. That thread became the debate, and derision, over how and why the modification functions. No agreement could be reached on the mechanism of action. All attempts to debate or even define richer, leaner, heat sink, inertia, conductivity and so on devolved into a thread where the technical content is all but impossible to retrieve.

 

There has been much interest in this Engine Temperature Sensor over the years. No one can be sure why Guzzi changed the holder to plastic. I would say if yours breaks, and you don't want it to break again, Guzzi dealers can sell you the brass sensor holder.

 

After two years riding with the brass holder and a thermal paste, I thought it important to post that my Sport runs better with the stock sensor holder and no paste. The difference with the Delrin holder with no metal or paste whatsoever is substantial; feels like a fresh tune up.

[GuzziMoto]

The observations of empirical changes by an experienced rider are not theoretical. Otherwise, winning race teams would not have their riders giving feedback to the technical people.

 

Certainly, my experience or observational abilities could be discounted. Yet, I'd say I know this bike pretty well, and that I've "tested" the three set-ups adequately to make valid observations.

 

Please note: this is not a continuation of the old thread. That thread became the debate, and derision, over how and why the modification functions. No agreement could be reached on the mechanism of action. All attempts to debate or even define richer, leaner, heat sink, inertia, conductivity and so on devolved into a thread where the technical content is all but impossible to retrieve.

 

There has been much interest in this Engine Temperature Sensor over the years. No one can be sure why Guzzi changed the holder to plastic. I would say if yours breaks, and you don't want it to break again, Guzzi dealers can sell you the brass sensor holder.

 

After two years riding with the brass holder and a thermal paste, I thought it important to post that my Sport runs better with the stock sensor holder and no paste. The difference with the Delrin holder with no metal or paste whatsoever is substantial; feels like a fresh tune up.

I have no doubt that changes to the ETS can effect the way the motor runs, and changes in the right direction could very well make an improvement for the better on a motor that does not run right.

I don't doubt your observational skills.

I am glad it has helped you.

[docc]

I have no doubt that changes to the ETS can effect the way the motor runs, and changes in the right direction could very well make an improvement for the better on a motor that does not run right.

I don't doubt your observational skills.

I am glad it has helped you.

 

I'll let you know how it goes when the ambient temperature turns off cold. I don't want to loose that magic on the crisp, cool morning rides!

 

With a "heat index" of 105F today (over 40C), which accounts for the oppressive humidity, I do look forward to those crisp, cool morning rides with the sound of Mandello Magic in the air!

[Dan M]

I'll let you know how it goes when the ambient temperature turns off cold. I don't want to loose that magic on the crisp, cool morning rides!

 

With a "heat index" of 105F today (over 40C), which accounts for the oppressive humidity, I do look forward to those crisp, cool morning rides with the sound of Mandello Magic in the air!

 

 

It'll be fine! That's my favorite riding weather as well.

[stormsedge]

Docc, noting your effort and comments early in this string...I think your solution is something I should attempt with my bike, unless someone has the GM part # as a more direct path. I have about given up riding in Jul-Sep here due to the heat and poor low throttle manners. k

[docc]

I thought I would post feedback on the cold weather results, but I just haven't ridden much this winter. When I have, the Sport has run well and never dipped back into the 32-33 mpg typical in cold weather past.

 

Still, there have only been a couple issues (other than the basic "tuning") which have helped my Sport's manners this much (totally corroded coil wire on the right coil and heat destruction of the main fuse).

 

Well, there was that bad TPS . . . and the broken connection inside the stator . . .

[motowarren]

So after reading some of these posts and having the bike apart anyway for a shock rebuild I decided to take my temp sensor out to see what it looked like from the other end. The first thing I did was break the bake-o-lite holder. So now I'm kind of committed to doing something with it. So I took it apart ala Docc's project. Picture of parts below. But I have some questions.

1. Is the white paste of any significance IE do I need it?

2. Can I use the original bottom piece that screws into the head or do I need to modify it somehow?

3. What gap do I need between the top and bottom piece and how much tolorence do I have?

I have a lathe and some acetal rod which I think is similar to Docc's delrin.

[docc]

1) No paste required.

 

2) How do you propose to attach your new acetal holder to the existing base? (Less mass is the goal with this modification and a simple short length of threaded copper rod works well).

 

3) 5mm air gap

[motowarren]

 

2) How do you propose to attach your new acetal holder to the existing base? (Less mass is the goal with this modification and a simple short length of threaded copper rod works well).

 

3) 5mm air gap

 

Docc, Attached is a drawing of my original brass piece that I reworked. I decided to do that since I didn't have a piece of brass or copper around. The first thing I did was to mill the hex down from 5/8 to 9/16 so I could get a wrench on it when it's in the engine. Then taking to heart your statement of the goal being to reduce mass to make it transfer heat faster I machined the rest of the brass fitting as per drawing At the position of the resistor in the brass fitting it will have 5mm clearance on all sides but obviously not to the bottom but that should work shouldn't it?

WRR_WaterSensor.pdf

WRR_Adaptor.pdf

[docc]

How much gap is there off the tip?

[motowarren]

How much gap is there off the tip?

 

In the PDF drawing titled water sensor(a misnomer)at the bottom you can see the complete assembled pieces and you can see the measurement from the tip of the resistor to the bottom is 20mm. However along the sides at the resistor it is about 5mm on all sides and I figure that's where it would get its reading from. Still close enough to the engine that it shouldn't be losing any of the heat transferred from the engine...I think...

[docc]

I'm thinking the whole premise has been for the sensor to lose the heat (not soak it up, therefor: "low mass") and find it quickly (hence the close tolerance to the metal connection to the head. All to contribute to better "responsiveness,"

[motowarren]

I'm thinking the whole premise has been for the sensor to lose the heat (not soak it up, therefor: "low mass") and find it quickly (hence the close tolerance to the metal connection to the head. All to contribute to better "responsiveness,"

I don't know. This is all an experiment for me. It's running good right now so I'll run it like it is for a while to check gas mileage and hopefully test it in some different climate conditions.