Crank sensor question 1996 Cali

[Thundergoose]

So, pulled my crank sensor yesterday. I noticed that it was mushroomed in the middle of the shaft. I had to get a screw driver under the tabs and lift one side, then the other...

Is this normal? Could this be what is causing my bike not to start?



[/quote]

[Tom H]

I'm not sure how it should look shape wise, but I do think it should have a shim/gasket that sets the timing.

http://www.harpermoto.com/parts-by-motorcycle/1990-2000-moto-guzzi-motorcycles/california-1100-1994-1997/digiplex-electrical-system-en-california-1100-1994-1997.html

On my 2004 it has various gaskets/shims available to set the timing if I remember right.

Any experts on this??
Tom

[tris]

Could be as the air gap between the sensor and the crank trigger is important

You need a Magnetti Marelli SEN813 - see here http://www.guzziriders.org/rpm-and-tdc-sensor_topic455.html

[Old Jock]

No expert but on my 1100 Sporti it looks like the same set up for the phonic wheel (why is it called that) anyway if memory serves there was a metal plate/shim below it

However I just checked the parts list for the Sporti and it only lists a gasket and O ring

The parts book states the gap on the Sport to be between 0.6-1.2 mm, so I reckon it should have something in the way of shimming

As for the bulge, I have no clue sorry,

John

 

[pat80flh]

Looks kind of suspicious to me, along with no(or intermittent) spark, crank sensor signal is a vital input for spark and injection. I don't know if guzzidiag will show live data, if you have it, see if it shows RPM while cranking. Or pass a piece of metal back and forth over the nose of the sensor with key on, should make a spark and trigger injectors. I'm guessing the sensor should generate about .5 AC volts if you can figure out which wire is the signal. Or toss a new one in, they do have a finite life.     

[balvenie]

On my 2004 it has various gaskets/shims available to set the timing if I remember right.

Any experts on this??
Tom

No expert here but my first observation was that the O-ring(?) is working very well because his engine is so clean.

Mine is an '04 Cali and had a number of shims. I don't recall a bulge in mine.

[rodekyll]

No expert but on my 1100 Sporti it looks like the same set up for the phonic wheel (why is it called that) anyway if memory serves there was a metal plate/shim below it

However I just checked the parts list for the Sporti and it only lists a gasket and O ring

The parts book states the gap on the Sport to be between 0.6-1.2 mm, so I reckon it should have something in the way of shimming

As for the bulge, I have no clue sorry,

John

I'm trying to understand the phonic wheel and sensor for a project I'm working on.  Right now, the way I understand it is this (might not be correct, but it works for me):

Phonics has to do with sounds, which have to do with frequencies.  A Phonic wheel has teeth placed at regular intervals, which is the definition of "frequency".  The wheel's frequency is discerned by the sensor.  The Guzzi frequency is 48/1, tuned by those teeth. 

The waveform the wheel generates can be sensed as either an analog sine wave (proximity sensor) or a digital 1/0, or high/low square wave (contact or optical sensor).  Guzzi uses a magnetic sensor, which gets a stronger signal as a tooth approaches it, peaks the signal as it passes, and then gradually loses it as the tooth moves on (rinse and repeat endlessly -- it's a circle).  So it literally hums a tune with an "analog sine wave at a frequency of 48/1". 

(If our sensor was a contact or optical device the teeth would be seen as "contact/no contact" or "light/dark" -- no rising or falling signal as the teeth approach and leave.  That would be a "digital square wave at a frequency of 48/1."  That's not relevant to guzzi, but it's relevant to phonic wheels.)

The frequency of the tune our wheel makes is interrupted by two missing teeth.  So the wheel "listens" for the interruption in the humming like your ear listens for variances in speech, and uses the change to sense the position of the wheel and trigger an event -- spark, injector, tach signal, whatever.

The ratio of 48/1 holds regardless of the speed of the wheel.  It's 48/1 stopped, and it's 48/1 as fast as it goes.  So the frequency itself only gives us the position of the wheel.  It doesn't tell us if it's in motion or how fast it's going, or whether it's speed is increasing, constant, or decreasing,  The ecu needs to add a time element to it's counting of teeth in order to come up with the cyclic rate +/=/- of the wheel. 

I'm sure someone with a better understanding will correct me.  :)

[fotoguzzi]

Yes it could be,
that bike can show fault codes including the sensors.. LED on dash? or under left side cover.. find the procedure in the FI supplement from Greg Benders site..
from memory, crank motor don't start bike but leave key on and the fault codes flash in between 3 long flashes and then it repeats .

I could not find the FI supplement on benders site now tho..

[Wayne Orwig]

It is obviously swollen, and may be failing. That ECU does not have a memory function to recall old fault codes but it can display some current codes.
You can easily test it with an ohmmeter.

The shimming does not set the TIMING, but it does make the pulse reliable. You do not appear to have any shims, so it is as close as it can go, so the signal is as strong as it can be. As long as the tip of the sensor has not touched the timing wheel inside, you are good.

[Wayne Orwig]

The frequency of the tune our wheel makes is interrupted by two missing teeth.  So the wheel "listens" for the interruption in the humming like your ear listens for variances in speech, and uses the change to sense the position of the wheel and trigger an event -- spark, injector, tach signal, whatever.

The P8 uses a second sensor on the flywheel to identify TDC. Then the cam sensor is to identify RPM.
From what the manual implies anyway.

[Kiwi_Roy]

Doesn't that bike have 2 of those sensors, another one sensing the flywheel?
You can measure the resistance from the ECU plug.   680 Ohms according to the link Fotoguzzi just posted
http://www.thisoldtractor.com/guzzi007/schematics/1996_California_1100i.gif 
Item 47 & 48, I have read somewhere that the flywheel sensor can get covered in iron scraps from the ring gear, it's a magnet with a coil wound over.

To check the gap set the motor so it's over a tooth and put a blob of something (I use JB Quick) on the sensor and bolt it home then measure it once set.

[fotoguzzi]

from the manual,
- 24 -
TROUBLE CODE 1.2
Phase  signal (TDC) failure
The trouble can be in the sensor itself
 (circuit opened), in the wiring or in the connector (circuit opened). It
can  also  be  caused  by  an  excessive  air  gap.  When  th
is  fault  is  intermittently  occurs  during  running  the 
code 1.2 is present together with the code 1.3.
When code 1.2 is present with code 1.3, check the air gap on the timing case sensor.

found here,
http://www.dpguzzi.com/efiman.pdf
page 24

I think phase sensor refers to the Cam sensor not the crank sensor but they are the same so buy one and try in cam hole first.

[fotoguzzi]

So, pulled my crank sensor yesterday.

Cam sensor shown.. there is also a crank sensor under right throttle body, have you clean the swarf off that one?

[Hahnda]

I have a '96 California also. A couple years ago it had a no-start issue. Would crank over fine but no fire. That sensor you show turned out the be the problem. I can't remember the values at the moment but when the sensor was tested it was bad. New sensor and no issues since. Somewhere in a manual there should be a value to compare to. Just need to find it. Other option is to take some readings off your other sensor and compare. Should be similar values.

[bad Chad]

It is obviously swollen, and may be failing. That ECU does not have a memory function to recall old fault codes but it can display some current codes.
You can easily test it with an ohmmeter.

The shimming does not set the TIMING, but it does make the pulse reliable. You do not appear to have any shims, so it is as close as it can go, so the signal is as strong as it can be. As long as the tip of the sensor has not touched the timing wheel inside, you are good.

My 99 had a similar issue.  I took it in to my tech who found that it was the sensor causing the problem.   I had taken it out early to put in a new gasket as it leaked out oil.  When I put it back I didn't put in the shims, he told me it was amazing that it would run at all!

[rodekyll]

Found my new one -- CAM sensor.  It is a more or less perfect cylinder -- no "swelling" look to it anywhere.

The P8 uses a second sensor on the flywheel to identify TDC. Then the cam sensor is to identify RPM.
From what the manual implies anyway.

I don't know how the two sensors work together.  The 15M does it all with a single sensor.  Part of what I'm trying to learn is what the crank sensor actually does on the P8.  There is very little written about this stuff.

[fotoguzzi]

Found my new one -- CAM sensor.  It is a more or less perfect cylinder -- no "swelling" look to it anywhere.


I don't know how the two sensors work together.  The 15M does it all with a single sensor.  Part of what I'm trying to learn is what the crank sensor actually does on the P8.  There is very little written about this stuff.

Motor RPM sensor
This is a variable reluctance sensor. It is mounted on the bell housing facing the flywheel assembly. The flywheel has 4 detector teeth set at 90° to each other. As each tooth passes, the sensor sends an AC signal (see diagram.). The frequency of this signal generates the information on the engine speed.
 
 
PMS (TDC) sensor
This is also a variable reluctance sensor. It is mounted on the timing case, senses cam shaft rotation and generates the information needed to know the position of the cylinders in relation to their combustion top dead center.


source: http://www.dpguzzi.com/efiman.pdf

[rodekyll]

Yes, that's about as much detail as I can get, too.  I'm going to have to wait till I get south and unpack the oscilloscope to really figure it out.  Remember those old automotive diagnostic scopes?  They worked good to give a picture of all that if you got creative with the leads.

[Wayne Orwig]

Motor RPM sensor
This is a variable reluctance sensor. It is mounted on the bell housing facing the flywheel assembly. The flywheel has 4 detector teeth set at 90� to each other. As each tooth passes, the sensor sends an AC signal (see diagram.). The frequency of this signal generates the information on the engine speed.
 
PMS (TDC) sensor
This is also a variable reluctance sensor. It is mounted on the timing case, senses cam shaft rotation and generates the information needed to know the position of the cylinders in relation to their combustion top dead center.

source: http://www.dpguzzi.com/efiman.pdf

Something doesn't add up.

The flywheel, for the P8 and Digiplex, has a 'double tooth'. That double tooth is for detecting TDC on the right cylinder.  So the bell housing/flywheel sensor is for TDC. Try mounting the flywheel out of time and you will learn that lesson.

[Kiwi_Roy]

Something doesn't add up.

The flywheel, for the P8 and Digiplex, has a 'double tooth'. That double tooth is for detecting TDC on the right cylinder.  So the bell housing/flywheel sensor is for TDC. Try mounting the flywheel out of time and you will learn that lesson.

Are you saying the sensor has to be in a specific location on the flywheel, the document seems to indicate there are 4 targets but doesn't specify where.
It would sure suck to have to pull the flywheel again just to re-locate it.

[tris]

I'm sure that the Digiplex on my 95 carby Cali only had the one sensor and that looked at the crank

I guess that if the "brain" saw a double pulse it could know it needed to fire the spark plug.

I also seem to recall that there was a jumper to move the ignition timing one way or another - I can't remember which though

No idea if any of these random thoughts are of any help though   

[fotoguzzi]

98 EV
Flywheel with four pegs,




disregard that it has a Convert cam, the cam sensor was a pin on the cam gear not a phonic wheel like later 15m with no crank sensor.

[Thundergoose]

So, just got off the phone with the only local dealer (Ride Now Motorsports) and they claim this sensor has been discontinued by Moto Guzzi, so they couldn't even order it in. Is that even possible???

Here is some info I found online regarding alternative sensors, in case this is true.

OE REFERENCE:   
Alfa Romeo   60810103
Fiat   7733001
Lucas   SEB163
Marelli   64820168010
Marelli   SEN8I3

 

USED IN VEHICLES:

ALFA ROMEO 145 1.4
ALFA ROMEO 146 1.4
FIAT Tempra 1.8
FIAT Tempra S.W./Weekend 1.8
FIAT Tipo 1.8
LANCIA Dedra 1.8
LANCIA Delta 1.8

Just ordered 5 from a Chinese supplier. Will post if they work and are decent quality. Have the original part on the way from MG Cycle in the mean time...

[pat80flh]

Not sure how guzzi does it, but in early automotive efi systems, the crank sensor is the main input, it gets the system going, the cam sensor basically told the ecm when #1 was at TDC, so the injectors could be fired sequentially. Car would run, albeit with a check engine light if the cam sensor is bad, would not run at all if crank sensor as bad.

[Kiwi_Roy]

Time to visit the auto wreckers
Either that or find someone who's parted out an EV
Actually they may even be the same on the V11s

[rodekyll]

A crank sensor can't tell when to fire a plug on a multi-pot 4-stroke engine.  You need a cam sensor for that.

[Wayne Orwig]

A crank sensor can't tell when to fire a plug on a multi-pot 4-stroke engine.  You need a cam sensor for that.

I assumed it fired twice.
The flywheels I looked at, one of the four tabs had a cut in it, to produce a double pulse at TDC.
In the case of the Digiplex, it only had the flywheel sensor, no cam sensor. So it had to have a waste spark.
Maybe the double tab thing was just Digiplex.

[rodekyll]

I was supposing a dedicated spark system.  I never thought about which system guzzi efi would use.

[drdwb]

These are available even though this one says they are out of stock. I just bought one to replace one on a 750 Breva, I'm trying to find where I got mine to post the link.
It wasn't 25 lbs and it came from the US with in a couple days.

http://www.ebay.com/itm/03-08-MOTO-GUZZI-BREVA-750-Speed-Pickup-Sensor-/171981906363?vxp=mtr&hash=item280aeba1bb

When I was doing the diagnosis on the 750 Breva this sensor became a suspect, it turned out not to be the cause but  when the discussion of spacers or no spacers came up I tried to keep an open mind, so I asked myself did the bike run ok without the spacers  on this sensor, if the answer is yes than why would it suddenly need spacers, it doesn't rule out the sensor being bad, and since the Breva came without spacers, and ran well before the problems started , I decided to replace the sensor as I found it, with out spacers. Keep it  simple. After  3 months of  trying to find an elusive problem,getting back to basics checking connections  a d testing sensors and systems helped locate the problem. Persistence pays off
Good luck , when I find the source I'll repost.


CRANKSHAFT-SENSOR-ALFA-ROMEO-145-146-LANCIA-DEDRA-DELTA-18783
Have one to sell? Sell it yourself
CRANKSHAFT SENSOR : ALFA ROMEO 145 : 146 : LANCIA DEDRA : DELTA : 18783
   
Seller information
tvrparts200 (4324  Feedback score: 4324)
99.8% Positive Feedback
 Follow this seller
Visit Shop: LSM Motor Parts Ltd