engine oil temp sensor

[rologuzzi]

Ratchet

 

Apologies for the confusion. What I should have said is that there’s no perceptible difference between the way it runs now & prior to playing with the sensor! It certainly isn’t running any worse, hence my belief that the sensor is still working (not cooked) despite its much closer thermal acquaintance with the head. It will be interesting to see whether this happy situation can be sustained.

 

Maybe I'm just lucky compared to some but my V11 has always run very well, right from new. Largely based on the collective wisdom of this forum, I've made some incremental improvements to the stock setup, such as careful TPS setup & TB synch as well as lubing the places that the Luigis seem to miss. I’ve carried out the specified periodic maintenance in the owners manual but beyond fitting a set of Staintunes, haven't messed with it.

 

For me, the issue that needs most attention now is suspension setup, but that's a topic for another thread.

 

Cheers, Tony

[Guest ratchethack]

Thanks, Tony. I've been on the verge of doing wot you did, reckon I'll pass for now.

 

BTW - Kudo's in advance for pursuing suspension setup.

 

It's the best return on effort & expense you'll ever get on your Guzzi, IMHO.

[Guest scrat]

Yesterday I did two things. First I replaced the head temp sensor holder with one made of brass, and filled the gap with heat conducting paste. Then I put in a new phase sensor.

 

Before I did this, the bike behaved like a rodeo horse, afterwards it was smooth as silk.

[Guzzi2Go]

Ok, I've been following this thread with interest, so here my If anyone wants or needs to comment, please go ahead. Keen to learn.

 

I'd say the sensor in question is in the place where our choke button(s) used to be. That said, I believe it acts more like an on/off switch than a fine regulator for fuel supply when the head temperature is between 90 and 91°C. As there is no contact between the sensor tip and the head, the sensor actually measures the temperature of the heads SURFACE rather then the "CORE". Remember, the sensor is attached to quite a large cooler (head's fins), by a large metal screw/thread (heat conductor) and separated from the head "inners" by air (heat insulator). Could one explain the heat "soak back" effect by the fact that the sensor cooled of quicker than the engine itself?

 

Few mililitres of oil "down the hatch" would probably improve the situtation. CPU grease is probably even better.

 

Here the datasheet of the sensor: http://home.planet.nl/%7Eworld.traveller/pics/wts05%20v4.pdf

[Guest scrat]

Few mililitres of oil "down the hatch" would probably improve the situtation. CPU grease is probably even better.

 

 

 

In my former life as a marine engineer, we used silicone oil with good results

[John A]

Some years ago when I modified my engine and got a FIM map I decided the automatic temp function was something I wanted to control myself.I had already made an aluminum sensor holder but still I thought it was too rich when the ambient temp was below 60F.I used a potentiometer and it operates like an electric choke.When it is below 65F the engine will not start unless I dial in some resistance.I remember I put a resistor in line,I think it was 5K, It is my belief that the ECU uses that to verify a functioning temp sensor.Some careful study of the books will need to be made,it was so long ago.I also use a DPDT switch so I can select either the potentiometer or the head temp sensor but it has been so trouble free I just use the dial.When it's cold out I used to switch it to the sensor but milage would drop into the mid 30's so soon after it starts I turn the dial to off or full warm.The engine runs perfectly in either mode,just rich when I select the temp sensor.I had this operation verified on the dyno when we installed and made the FIM ECU maps. Hope this helps someone and a note to Pete : I'm fulla shit too so don't let it bother you! John

[dlaing]

Yesterday I did two things. First I replaced the head temp sensor holder with one made of brass, and filled the gap with heat conducting paste. Then I put in a new phase sensor.

 

Before I did this, the bike behaved like a rodeo horse, afterwards it was smooth as silk.

How did you determine that you needed a new phase sensor?

Happy to hear it worked

 

Hope this helps someone

Thanks, it will help me and I am sure others.

My cold gas mileage is bad and this gives me confidence to remap the temperature correction using TuneBoy as the ECU pretty clearly over enrichens when cold.

For those without TuneBoy, a little thermal paste should reduce the rich condition.

[Guest scrat]

How did you determine that you needed a new phase sensor?

Happy to hear it worked

 

I have learned the hard way, I also own a Citroën CX GTI. When the phase sensor started to go bad, the car

became hard to start when warm,engine stumbling,rev.counter down to zero when engine was running.

So when the MG started to do the same, I was quite sure where to begin

[pete roper]

I also use a DPDT switch so I can select either the potentiometer or the head temp sensor but it has been so trouble free I just use the dial.When it's cold out I used to switch it to the sensor but milage would drop into the mid 30's so soon after it starts I turn the dial to off or full warm.The engine runs perfectly in either mode,just rich when I select the temp sensor.I had this operation verified on the dyno when we installed and made the FIM ECU maps. Hope this helps someone and a note to Pete : I'm fulla shit too so don't let it bother you! John

 

This is very interesting and ties in with what I would of expected. More sophisticated than my toggle switch idea but. Interestingly over the last week or so I've been watching the fuel consumption on the Griso very carefully. As you may or may not know the *new* models have all sorts of silly bling in their dashboards. One of these is a function that tells your fuel consumption in Litres per 100Km. Now when you start the bike up it's always awful 7.8 to 8.2 L per 100. It takes about 25Km for the figure to stabilize, (You have two trip functions on the new dashboards so you can do a fuel consumption from cold and then when you reckon it's hot enough you can re-set the second one and start with a 'Hot' reading.) Consistently over summer consumption when hot has indicated, (And this is only an indication, the function seems consistent but pessimistic!) the machine said it was using 6.0 to 6.2 L per 100 but now the weather has got cold this has gone up to 6.4 per 100 or higher even when it's raining which would seem to confirm what I've always thought about big blocks, especially squarefins, being over finned to buggery!

 

So what does this all mean? Well, I dunno really but it would seem to indicate that the variable nature of the signal from the ETS does have a consistent effect in varying the fuel delivery. In a lot of ways I'd like to do what John has done and give myself the choice to take it out of the equation. There again the Mighty 'G' runs so sweetly at any time I really can't be bothered.

 

John? I hope your last comment wasn't an indication that you think I think you're full of sh!t? I don't always agree with people, (look at the vitriol I'm copping over on Phil's board for having the temmerity to disagree with someone!) but I'll always respect their opinions unless they suggest people do something that is downright dangerous! Your sollution seems elegant and extremely sensible to me!

 

Pete

[John A]

No Pete,I was putting us both in the same pile,seems that people who actually think about things and do experiments to achieve a desired out come are often the brunt of someone's ire.I really appreciate the way you press on while I won't even tell most people about some of the things I've done because I would have to argue some pretty basic stuff and teach class and they still scoff and won't believe me,I just don't have the drive to do that anymore and admire that you do and hope you will continue,it inspires me. Thanks,and Best Regards,John

[guzzijack]

Here's my FWIW.

 

The validity of ensuring that the temp sensor is making good thermal contact with the pocket in which it sits - either plastic or brass - was brought home to me when Pete Roper plugged his Axone into a V11 Jackal when he was up here in the UK last time. The owner was reporting bad MPG figures and, surprise, surprise the temp readout for the ECU on a fully warmed engine was only something like 38 degrees, (I think, correct me if I'm wrong Pete).

 

After whipping the sensor out and filling the plastic holder with copper grease, the temp readout was immediately in the upper 70s and the owner has since reported better driveability and higher MPG figures. I don't think the brass pocket will make a lot of difference to the above scenario but then again I can't directly compare the figures I'm getting from my Centauro with the brass holder, as that will always run hotter than a 2 valve engine.

 

Re. the phase sensor - I would urge anyone with a V11, V10 or any engine that uses one to spend around £32 and keep a spare on the bike. The previous poster was either very lucky or very experienced if he could identify his going bad. I had one go out on another Centauro while tooling along at about 120 mph and they don't give you any notice It's the one thing that will kill an engine dead and cannot be bypassed or a workaround done. So get one or keep your recovery cover up to date!

 

Now, how about those timing gears Mr Roper?

 

GJ

[pete roper]

Here's my FWIW.

 

The validity of ensuring that the temp sensor is making good thermal contact with the pocket in which it sits - either plastic or brass - was brought home to me when Pete Roper plugged his Axone into a V11 Jackal when he was up here in the UK last time. The owner was reporting bad MPG figures and, surprise, surprise the temp readout for the ECU on a fully warmed engine was only something like 38 degrees, (I think, correct me if I'm wrong Pete).

 

After whipping the sensor out and filling the plastic holder with copper grease, the temp readout was immediately in the upper 70s and the owner has since reported better driveability and higher MPG figures. I don't think the brass pocket will make a lot of difference to the above scenario but then again I can't directly compare the figures I'm getting from my Centauro with the brass holder, as that will always run hotter than a 2 valve engine.

 

GJ

 

And I see this time and time again. While I can give no guarantee that the actual temerature reading given by the tool is accurate it is, or at least seems to be, consistently, inaccurate . I'm not telling people that this is a panacea for all ills. Simply that it is something that is worth checking and if there IS a false reading being obtained by the 'pooter it can, if it is off by a large enough amount, make a noticeable difference to both performance and fuel ecconomy.

 

 

Now, how about those timing gears Mr Roper?

 

GJ

 

Watch it Jacko or I'll come over and bash ye with me handbag!

 

Pete

[Gio]

I just removed the sensor (have the brass holder replacement ready) but unfortunately the black plastic top part disintegrated - can anyone suggest how to temove the lower metal part of the stock holder that fits into the head - I assume this part is also threaded (as per brass replacement) and so requires a very thin-walled 16 or 17mm socket ...? Vice grips ...? Dynamite ...?

 

Gio

 

PS - with sensor mounted in replacement brass holder - at shop temp (~20c) = 3.73kohm (spec = 3.75), in ice/water (0c) = 9.6/9.9 kohm (spec = 9.75)

[dlaing]

I forget which fittiing I used, but it was one that wedged in nice and bit will enough to get it out.

[luhbo]

What we are looking for is the temperature around the combustion chamber. Therefore the OEM used plastic part, properly assembled, is perfect (as long as it doesn't brake, of course).

The brass replacement may be rocksolid, but it transfers more heat off of the NTC, cools it down. I'm not sure of how much effect this has, but the hotter NTC is, for sure, in the plastic housing (again - as long as it's properly assembled!).

 

BTW, on my bike I can monitor the head temperature on Cliff's Optimiser. After about 3 miles it shows 75°C (ambient 10°), operating temp. is about 95°C (ambient 20°C). Interesting is the fact, that at idle it rises rapidly to 120° and more. 125°C I can see also when I show off the Quat-D while cruising between all those Coburg street cafès The temperature rises fast, but goes down only very slowly and never in city traffic!

 

Hubert