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engine oil temp sensor


nigev11

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after months of perfect running, my v11 rm started acting wierd; best described as feeling liek the choke was permanantly on. Plugs black as soot, rough running but under full throttle goes like a cut snake, wont idle.

 

new plugs, new caps, no difference.

 

by all accounts ive been advised this is most likely to be a problem with the engine/oil tem sensor located on the rear of the rh head.

 

I followed the manuals instructions (put a spanner on it and take it out and teh sensor came out just fine. Did same to the "oil temp sensor stand off" and "snap" it breaks into peices. WARNING; these are brittle plastic and easily broken.

 

Thansk to lots of help i found replacements and will fit them tonight along with some dialetric grease to ensure the senor is getting good conduction of heat and thus, the right message to the ECU.

 

Questions:

1 I was told ametal/brass replacement was available but the local guzzi distrubutor wasnt aware of one

2 Anyone explain to me how the hell you are supposed to screw the plastic stand off back into the head with decent tension and NOT breaking it?

3 Anyone else had a similar experience with poor running and this being teh solution?

 

thanks !

 

nigev11

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I've only done it once, but I seem to recall taking the plastic piece off with the temp sensor still screwed into it. That may give the plastic piece more strength. But the metal piece is a better idea. I seem to recall people putting things in the gap between the sensor and the head when installed to improve heat transfer to the sensor.I think .

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Isn't dielectric grease an insulator, and wouldn't that prevent proper voltage signal to ground? I would suggest antiseize. Joe

 

PS just gave this some more thought, and if the part is mounted in plastic, it must ground a different way. DOH!

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Apparently dielectric grease does not conduct electricity, but it does not prevent metal to metal contact. It does shield the metal to metal contact so it does not corrode. There are things like Kopr-coat, that conduct electricity and heat, you can use. I thought I heard someone saying they put a ball bearing in there to help conduct heat from the head to the sensor.

I think the sensor has a ground wire and all you need to woory about is temp transfer

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Isn't dielectric grease an insulator, and wouldn't that prevent proper voltage signal to ground? I would suggest antiseize. Joe

 

PS just gave this some more thought, and if the part is mounted in plastic, it must ground a different way. DOH!

 

Yeahbut...

 

Thermal conductivity is closely allied to electrical conductivity, so the copper anti-sieze [nickel A/S also would work, but w/ necessarily decreased electrical/thermal conduction] should remain a better choice than dielectric grease, not to mention the heat factor, which is where A/S goop comes into play anyway. Clearly, the grounding issue is irrelevant if the brass standoff is the preferred replacement as seen above [& in other threads here on v11LM.com...]

 

For the simple fact that the plastic standoff will inevitably become embrittled from the heat & fail when attempting removal at some future date, besides not functioning as well as the brass part, seems to indicate that this part is a part of the "early retirement program" for any Guzzichondriac, along w/ the stock relays & the dipstick markings...

;)

 

Ride on!

:bike:

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Guest ratchethack

For the simple fact that the plastic standoff will inevitably become embrittled from the heat & fail when attempting removal at some future date, besides not functioning as well as the brass part, seems to indicate that this part is a part of the "early retirement program" for any Guzzichondriac, along w/ the stock relays & the dipstick markings...

Makes perfect sense to me. Mine ain't broke yet, but I'm putting one on my next parts list to replenish "spares" stock, along with a Stucchi or Valtek cam-chain tensioner. Looks like the plastic thing ain't none too likely to survive a top end job anyway. . .

 

:thumbsup:

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Errr? Guys. Unless Im seriously mistaken the ETS is a simple thermistor. It doesn't ground to *earth* at all. What it does is increse the resistance in the body of the unit as it heats up. This is the reason it has more than one wire going into it :homer: . It's not like the oil pressure switch for example which is a simple 'Off/On'.

 

In my experience what *Appears* to be the problem is that the tip of the sensor doesn't make contact with the *bit* in the mount that screws into the head. This means that there will be an air gap and air is a really good insulator so even in the *secured* environment the temperature differential will be enough to cause problems.

 

It's interesting this has come up as I was at a rally this weekend and took my Axone tool up with me purely to show anyone who was interested what it could tell you about your bike. I plugged it in to several bikes, both V11's and Calis, and I think that most of the people who were there (Morris Sod was one of 'em.) would agree that the temperature reading being sent to the computer was CONSISTENTLY considerably lower than the actual head temperature. In some cases by many tens of degrees centigrade.

 

Now just call me 'Mr. Stupid', (And the local Guzzi Guru told one owner that what I had said was 'Bullshit') but if the ECU is being told that the engine is cold it's going to deliver more fuel to it? No? If you aren't going to have a variable delivery system why bother with an ETS? Why not just have a 3 position 'Toggle switch' that will send a choice of one of three signals to the ECU, one for 'Cold', One for 'Hot', and one for 'F#cked if I know?' somewhere in the middle? You'd always be able to get the motor running, it is after all what a conventional *Choke* on a carb does, innit? So working on the principle that the ECU is getting a false temperature reading it will tend to consistently over fuel. This will lead to poor fuel ecconomy and, oddly enough. a tendency for the engine to foul plugs and run like a munter in traffic. STRANGELY ENOUGH exactly the symptoms that the owner who the 'Guru' told my theory is 'Bullshit' is suffering from. Did it make me a bit cranky to a.) be treated like a c@nt for offering to try and help someone? Yes, a bit, even though the object concerned was pissed off his face and looking to be beligerent. b.) Be labeled as a BS artist by someone who couldn't be bothered to approach me and even discuss it, (Hey! I might of LEARNED something, but all this stuff has to be kept *secret*, eh? :vomit: ). Yeah? Well @#!#$# 'em. It'll be a cold day in hell before I attend that rally again. (No reflection on Morris or the 'Nevilles' in this, they seemed genuinely interested, and all I was trying to do was show people something they wouldn't usually see. :huh2: )

 

Who knows? I might be completely, brain-dead wrong, (Although I think any manual will tell you otherwise, they even tell you how to test the thermistor the 'Old Way' with a kettle and a mercury thermometer :oldgit: ) but I'll wager a barn full of bloated Bulgarian bibliographers that while a playing up ETS might not be the only problem the fact that it's staring him in the face like an excited peadophile it is certainly worth addressing and can't be lumped in as 'Bullshit'.

 

Gah! That sort of shit really hacks me off. I left the rally at 7.00AM this morning and just got back to Bungendore. 1178 Kms in 13.45. Not bad for an old git on a Griso with a wogged pipe! :grin:

 

Pete

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Pete,

 

Thanks for sharing your experience.

 

I believe that my bike just got into this 'constant choke effect', I noticed the un-rested idling while hot and the spark plugs are as black as the inner of a firewood stove.

 

I really would like to know the resistance of the temp sensor has while is hot.

 

I guess one switch and a resistance will replace this part for a manual solution 'open' will provide full choke and the resistance will provide 'no choke'...

 

I am afraid to burn the electronics by not using proper resistance values.

 

Thanks again :mg:

 

Anthro

 

Guzzi_partial_right_hand_si.jpg

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My bike was showing conflicting symptoms. I knew it was running lean. Asked my dealer about it and he said "You wouldn't believe how lean it's running." That's when I knew I had to stop going to that dealer.

 

The conflict is that it was also getting horrid mileage. And running like shite. As if the choke was on full time.

 

TPS was found to be 460mV. Explains why it was running lean! Replaced the temp sensor with a brass one - spun up a bit of brass to fill the air gap in the sensor and a bit of thermal compound (used in electronis to transfer heat from component to heat sink) so as long as sensor is working it has to be reading temp correctly.

 

Immediate difference! TPS set at 520mV and new sensor housing in, and mileage is leaps and bounds better! Best as I can figure, the low TPS was creating a lean condition in the low revs and at higher revs poor temp sensing was telling the ECU to dump gobs of fuel in. Just a theory but makes sense...

 

Granted I did make two significant changes - but I am sure that getting a correct head temp reading is a big part of getting the bike running right.

 

Ignore the naysayers, Pete. Some folks just have to be argumentative about everything! Public recognition needed to feed their egos. You are certainly right about the sensor. Not referenced to ground through the housing. It is just an RTD of some sort, likely a thermistor.

 

cheers,

 

Rj

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A brilliant rant, Pete! One of the best this year.

 

Death to false Guzzi-gurus! (that is a nice Tshirt motif, innit??)

 

And what you say makes perfectly sense. To me the issue with the temp sensor explains why the Goose engine often behaves differently on different runs the same day, for instance. Often it gets better when it has been run hard and then left standing for a ten minute pee break. Perhaps then the heat has been allowed to transfer to the sensor without any cooling by wind/air? It also runs better the hotter it gets outside.

 

For my feeble mind it seems that this little tweak is as important as the relay fiddling.

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And what you say makes perfectly sense. To me the issue with the temp sensor explains why the Goose engine often behaves differently on different runs the same day, for instance. Often it gets better when it has been run hard and then left standing for a ten minute pee break. Perhaps then the heat has been allowed to transfer to the sensor without any cooling by wind/air? It also runs better the hotter it gets outside.

 

 

 

This is the phenomenon of heat 'Soak Back' and yes, if you have a poorly reading/poorly contacting ETS these are precisely the symptoms I'd be looking for. Mind you I'm a complete f#ckwit so what would I know?

 

Pete

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This makes perfect sense. I was aware of the temp sensor up front of the the left cylinder, but the same treatment has to be done to the oil temp sensor behind the right cylinder?

 

What does the contact insert look like? Just a scrap of metal shaped up somehow?

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Guest ratchethack

This makes perfect sense. I was aware of the temp sensor up front of the the left cylinder, but the same treatment has to be done to the oil temp sensor behind the right cylinder?

Docc, from the title of this thread, there may be some confusion about wot sensor's wot here. :huh:

 

The engine temp sensor is screwed directly into the inboard-rear of the right-hand side cylinder head.

 

There are 2 sensors in front of the left cylinder set in the engine case behind the cam chain case. The lower one is fixed by two socket-head screws. It's the timing sensor. The top sensor screws in. It's the oil pressure sensor. The OPS doesn't require any attention unless/until it fails to switch contact to ground at some ridiculously low pressure of a few lbs.

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Errr? Guys. Unless Im seriously mistaken the ETS is a simple thermistor. It doesn't ground to *earth* at all. What it does is increse the resistance in the body of the unit as it heats up. This is the reason it has more than one wire going into it :homer: . It's not like the oil pressure switch for example which is a simple 'Off/On'.

 

In my experience what *Appears* to be the problem is that the tip of the sensor doesn't make contact with the *bit* in the mount that screws into the head. This means that there will be an air gap and air is a really good insulator so even in the *secured* environment the temperature differential will be enough to cause problems.

 

It's interesting this has come up as I was at a rally this weekend and took my Axone tool up with me purely to show anyone who was interested what it could tell you about your bike. I plugged it in to several bikes, both V11's and Calis, and I think that most of the people who were there (Morris Sod was one of 'em.) would agree that the temperature reading being sent to the computer was CONSISTENTLY considerably lower than the actual head temperature. In some cases by many tens of degrees centigrade.

 

Now just call me 'Mr. Stupid', (And the local Guzzi Guru told one owner that what I had said was 'Bullshit') but if the ECU is being told that the engine is cold it's going to deliver more fuel to it? No? If you aren't going to have a variable delivery system why bother with an ETS? Why not just have a 3 position 'Toggle switch' that will send a choice of one of three signals to the ECU, one for 'Cold', One for 'Hot', and one for 'F#cked if I know?' somewhere in the middle? You'd always be able to get the motor running, it is after all what a conventional *Choke* on a carb does, innit? So working on the principle that the ECU is getting a false temperature reading it will tend to consistently over fuel. This will lead to poor fuel ecconomy and, oddly enough. a tendency for the engine to foul plugs and run like a munter in traffic. STRANGELY ENOUGH exactly the symptoms that the owner who the 'Guru' told my theory is 'Bullshit' is suffering from. Did it make me a bit cranky to a.) be treated like a c@nt for offering to try and help someone? Yes, a bit, even though the object concerned was pissed off his face and looking to be beligerent. b.) Be labeled as a BS artist by someone who couldn't be bothered to approach me and even discuss it, (Hey! I might of LEARNED something, but all this stuff has to be kept *secret*, eh? :vomit: ). Yeah? Well @#!#$# 'em. It'll be a cold day in hell before I attend that rally again. (No reflection on Morris or the 'Nevilles' in this, they seemed genuinely interested, and all I was trying to do was show people something they wouldn't usually see. :huh2: )

 

Who knows? I might be completely, brain-dead wrong, (Although I think any manual will tell you otherwise, they even tell you how to test the thermistor the 'Old Way' with a kettle and a mercury thermometer :oldgit: ) but I'll wager a barn full of bloated Bulgarian bibliographers that while a playing up ETS might not be the only problem the fact that it's staring him in the face like an excited peadophile it is certainly worth addressing and can't be lumped in as 'Bullshit'.

 

Gah! That sort of shit really hacks me off. I left the rally at 7.00AM this morning and just got back to Bungendore. 1178 Kms in 13.45. Not bad for an old git on a Griso with a wogged pipe! :grin:

 

Pete

Glad you had a good trip home Pete,I just got home today.

Don't worry about the {Guru}.The place is full of them.Thats why I suck as much off this forum as I can,cause I don't trust anyone up here, and your to far away.We the {Nevilles},go to Mingoola for the good run on our bikes and to see a few mates and some nice bikes.Not to get info,we only get that from you on v11 site here.It was great to spend that 10 mins with you,I tried to suck in all the info as good as I could.Hope to see you again some time.

from the bloke who won The best NOTE :bier:

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