Wildguzzi.com
General Category => General Discussion => Topic started by: willard on January 16, 2018, 08:32:40 AM
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So it's been cold in Georgia, but I decided to run the Breva to work yesterday. Started fine, idled smoothly, felt great. Then as I was just about to get on the highway, sitting at a red light, I notice the oil light is on! :embarrassed:
I immediately hit the Killswitch and pull the bike over to the median. Sitting on the seat and keeping the bike upright I check the oil... It's fine. Above the min level on the dipstick. Okay, I think, maybe I'm not on level ground? So I turn the bike a bit and everything looks level. I check the oil again... It looks the same. So I chance it and start up the bike again. The oil light flickers off as it does just after starting, and I shift into first. No light! Then I shift back into neutral and the light come on again. :shocked:
I repeat the oil checking process. Looks okay, still. I'm thinking the oil pressure sensor maybe went bad.
I decided to continue on my way to work to avoid being late. I paid very close attention to the dash. That's when I noticed that the oil light would come on only when the transmission was in neutral. Almost as if it were wired to the neutral light itself.
Any ideas? Riding home at about 33 degrees I didn't see it come on at all.
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Sounds like a fussy switch w/it's cold temps, dash wiring most likely has a common ground for the lites.
Believe the dipstick.
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First I don't know the Breva at all
The pressure switches on the early bikes were/are notoriously bad the sensors quoted in the diagram I know anything about.
Both neutral switch and oil pressure sensor go straight to the dash according to Carl Allison's diagram, so it might be worth having a poke around there to make sure all the connectors are secure. Both are neutral and oil pressure warning are negatively switched (circuit made when the negative side is grounded) which makes me suspicious
If you've rode it a bit since the light has been coming and the bike has not made any death rattle noises then it's almost certainly not real
If it was mine I'd either change the sensor/switch/whatever the hell it is, to eliminate OR at least get a pressure gauge on it to put my mind at rest.
Hopefully more knowledgeable minds than mine will chime in
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Was it raining at all?
Have they been salting the roads in your area?
Often the switches will track across the insulator, I have even seen incandescent lights turn on, I'm sure the Breva dash inputs are way more sensitive to stray current.
The switches are really not very good, it's hard to expect them to be reliable with such small working parts.
I have pressure gauges on my Guzzis, they typically idle at 1/3 to 1/2 of normal pressure (60 psi) and as little as 10 psi when hot at a slow idle.
I can't explain the light on in Neutral, is there any way the Breva idles slower when in Neutral?
If you are worried add a 100 psi gauge.
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It wasn't raining.
I went outside today to see if the problem was still there. I started up the bike and no oil light! But... The left blinker kept coming on!
What is happening...
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It wasn't raining.
I went outside today to see if the problem was still there. I started up the bike and no oil light! But... The left blinker kept coming on!
What is happening...
You mean it would start to blink without the switch being used?
I think I would start by making sure the dash has a good ground on pin 25
No salt on the roads either?
I wonder if there is a common multi pin connector they go through, check for corrosion in those perhaps.
The connector from the LH switch
Water in the dash?
In the dash connector?
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Take off dash, clean pin connectors & reassemble w/coated pins. KYJelly works
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Didn't we have a case of mistaken identity here some years back where the rider was confusing a neutral light with the oil light ?
Dusty
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KYJelly works
Hmmm..
Aparrently so. :wink:
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Recent oil change to a different viscosity?...
How many miles maybe it's time for she'll bearings etc
Unusually cold temps...head temp sensor? Reading confused? So cold you really did need a thinner weight?
Distance to light was just right for the fast idle to drop to a not quite warm enough slow idle...
A problem never repeated isn't, until it does, then it is............. :popcorn:
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I would disconnect neutral light switch at gearbox first.
Actually first thing that should go anyway, if you don’t know when you’re in neutral not sure how you could ride a bike.
Sounds to me that there’s a short in dash twixt oil and neutral senders.
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Neutral switch goes to ECU, oil pressure goes to dash so I doubt the two are actually shorted
Sent from my shoe phone!
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There is water in the dash. Lots of condensation over the digital display. I'll try to take it apart and clean the connectors tomorrow.
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Didn't we have a case of mistaken identity here some years back where the rider was confusing a neutral light with the oil light ?
Dusty
Correction , it was between the generator and oil light .
Dusty
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Neutral switch goes to ECU, oil pressure goes to dash so I doubt the two are actually shorted
Sent from my shoe phone!
That set me wondering Roy
Looked again on the 2004 according to Carl both go to the dash, 2005 and it is as you state.............. ......bloody Guzzi!!!!!
I was wondering as already stated if it was a bad ground at the dash and the lights were searching for a path, but both these lamps are activated on the ground side. That said as all they need is ground path to light if there was a bad earth or some form of short on the oil pressure light, it could well cause the oil pressure light to illuminate when the neutral had a path to ground.
I'm also very suspicious of the fact that the dash has a lot of condensation the fault could be right there.
As others have stated could be a low idle, as far as oil the cold weather surely it is going to make the oil viscosity higher if anything, so pressure would rise and damp should probably be less at lower ambient temp all things being equal
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My experience with my breva 1100, I would change out the pressure switch. the oil light would come on at idle from time to time, no rhyme or reason. Once I changed it, I haven't any issues with oil light coming on since.
Old Head
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Old Jock said..
That said as all they need is ground path to light if there was a bad earth or some form of short on the oil pressure light, it could well cause the oil pressure light to illuminate when the neutral had a path to ground.
I *think* that's a winner..
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Well it's 15 degrees out now with a rare Georgia snow, so it may be a while before we find out.
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15 degrees would be a heat wave around here.. :cool:
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I don't know if this helps much, but on the 2TB small blocks the wires from the oil pressure sensor and the neutral sensor join in a 2 pin connector just under the top frame (it's under the tank), from where it disappears into the wiring harness, presumably heading towards the dash. So at least in some of their journey they are close to each other. The workshop manual lays out procedures for testing these sensors and their wiring. Wasn't easy to wrap my head around it, but I perserved & identified the failed oil pressure sensor. My symptoms were not the same as yours, mind, but the testing procedure seems to allow for various contingencies. Best of luck.
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Update
I changed the oil and filter and have ridden the bike a few hundred miles. The oil light has not come on since. It could have been the cold/water in the wires. It was the first time I had ridden in a week or two and it had just rained.
I will note that the left bolt holding the dash in place seems to have sheared off or the plastic has broken. It wobbles around easily, but is still held in place. Maybe that contributed to it somehow?
The "Startus Interuptus" fix is desperately needed on my bike, and I still need to have the holes in the mufflers welded over. We'll see if the problem persists at all, but these fixes are my priority as of the moment.
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I would disconnect neutral light switch at gearbox first.
Actually first thing that should go anyway, if you don�t know when you�re in neutral not sure how you could ride a bike.
Funnily enough Martin, it is quite useful on the Breva. Some can be quite notchy in the first gear dept (mine has always been good) and if you are struggling to find neutral when you are stopped the light can be a godsend.
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The "Startus Interuptus" fix is desperately needed on my bike, and I still need to have the holes in the mufflers welded over. We'll see if the problem persists at all, but these fixes are my priority as of the moment.
http://www.thisoldtractor.com/guzzi007/schematics/2004_750_Breva.gif
Very easy to do on your Breva, see the red wire going into the Start relay Pin 5 snip it an inch or so away and feed it from a new 20 Amp fuse at the battery via at least an 18 gauge wire, the wire from the relay to the solenoid should be #18 as well, #16 would be even better.
Leave the original wire feeding the other relays
If you need any further help send me a PM
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http://www.thisoldtractor.com/guzzi007/schematics/2004_750_Breva.gif
Very easy to do on your Breva, see the red wire going into the Start relay Pin 5 snip it an inch or so away and feed it from a new 20 Amp fuse at the battery via at least an 18 gauge wire, the wire from the relay to the solenoid should be #18 as well, #16 would be even better.
Leave the original wire feeding the other relays
If you need any further help send me a PM
Thank you! I'll get it done asap. I have a hunch that my new battery isn't being charged very well either, so this fix will help me narrow down that issue.
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Thank you! I'll get it done asap. I have a hunch that my new battery isn't being charged very well either, so this fix will help me narrow down that issue.
With this new information - it could be a bad battery or ground connection, that would effect starting and charging. Scrape the connections and use some Vaseline. make sure you do the main battery ground connection to the chassis also.
The regulator ground used to be a problem on earlier models, the regulator is set to put out ~13.8 - 14.2 Volts, if it's not making good contact to ground you might be losing some Voltage there. Wouldn't hurt to clean the ignition switch contacts as well.
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Update
I will note that the left bolt holding the dash in place seems to have sheared off or the plastic has broken. It wobbles around easily, but is still held in place. Maybe that contributed to it somehow?
Between this and rain yes, nothing like a mechanical failure to cause a lectric one.
Def proven it wasn’t oil pressure, now disconnect neutral light at gearbox, problem will never return
Funnily enough Martin, it is quite useful on the Breva. Some can be quite notchy in the first gear dept (mine has always been good) and if you are struggling to find neutral when you are stopped the light can be a godsend.
Better to fix clutch or change gearbox oil imho
Grew up with triumph clutches, had to learn to find neutral moving, still do it but Guzzi boxes and clutches sb and bb don’t have this issue unless something is wrong, light will not fix problem.
Does anyone need a neutral light in a (manual) car ?
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With this new information - it could be a bad battery or ground connection, that would effect starting and charging.
I recall the early smallblocks didn't have the dedicated ground from the battery to the frame+regulator, that the later models have. Adding a ground wire from the (-) battery to the frame and regulator could only help.
Joe
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I recall the early smallblocks didn't have the dedicated ground from the battery to the frame+regulator, that the later models have. Adding a ground wire from the (-) battery to the frame and regulator could only help.
Joe
Good information right there.
Tell us some more about your starting problem, do yo just get a quiet click and nothing else or do you get a fairly loud clunk and no rotation. I.m trying to figure out if it could just be a weak battery due to lack of a good charge.
Does it play up after its been on charge?
Is the bike left outdoors or kept in a garage?
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Good information right there.
Tell us some more about your starting problem, do yo just get a quiet click and nothing else or do you get a fairly loud clunk and no rotation. I.m trying to figure out if it could just be a weak battery due to lack of a good charge.
Does it play up after its been on charge?
Is the bike left outdoors or kept in a garage?
It's kept outdoors. When the battery is charged it roars to life in no time. But after riding a while, without a charger, it takes a few rotations before it starts. The trouble I'm experiencing is different from a dead battery. It quietly clicks and then nothing.
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That certainly seems like Voltage drop to the relay then, its a common problem, I remember looking at a 750 Breva from NY at the last national (John Day), same symptoms. The elderly gentleman had figured out how to jump start it at the starter terminals.
Look further back to my reply No 22
BTW, cleaning the ignition switch might improve it for a while but a stronger feed to the relay will be permanent. The wire from relay to solenoid can be another weak point, minimum 18 AWG 16 even better.
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The wire from relay to solenoid can be another weak point, minimum 18 AWG 16 even better.
K-Roy,
Is thin wire feeding the solenoid a known weakness of the 750 engine, or is this just a general statement?
Joe
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Update
I will note that the left bolt holding the dash in place seems to have sheared off or the plastic has broken. It wobbles around easily, but is still held in place. Maybe that contributed to it somehow?
On my wife�s 750 the PO had dropped it a couple times broke turn signal and windsheild mount on right side,dash very wobbly, the both rubber mounting bolts had bolts out of rubber, I tried to fix with silicon, left hand side the fix worked, right hand needed repair 2 more times, I thought I was just making it to tight, bought new one from dealer. Installed but didn�t over tighten, still pulled out, even though I inspected mounting very carefully, couldn�t see any problem, I did silicon fix again, but reinstalled with 2 washers as spacers, 2000 miles since still ok. So something was misaligned.
Wife loves the bike, So do I, It�s a blast to ride, so lite,nimble and quick, great bike for one up touring for her, and when she lets me, I enjoy thrashing it on the back roads, sometimes it�s more fun than my Norge. But there are little things that a little more quality or perhaps thought or expense in production and finish would make a better product. Too bad it had such a limited run.
Thanks for the post, I am always thankful for the info I get from this forum that help keep our Guzzi�s going.
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Too bad it had such a limited run.
It was close to 5 years out here.
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K-Roy,
Is thin wire feeding the solenoid a known weakness of the 750 engine, or is this just a general statement?
Joe
More of a general statement,
I wasn't actually having a problem with my Griso yet, I just thought I would check it out for Startus Interrupts potential, I fully expected to find the start relay wired through the ignition switch like most other modern Guzzi but no, for this year they wired it direct (similar to the MPH kit) but I was shocked to find a tiny wire from the relay to solenoid, the equivalent of 20 gauge, if they can do it on this model who knows what is done on others.
I calculated that for a decent current it would drop 15% of the Voltage. Later Grisos have a wire more like 18 gauge, still on the light side IMHO
Before I started I topped up the battery with a few hours on the tender.
Using my Oscilloscope I measured the current flowing to the solenoid, from the trace you can see how long it took from the time the start relay closed to when it started cranking. The current shot up from zero to 22 Amps, wavered around a bit as the solenoid moved in the magnetic field and dropped to 10 Amps as soon as the main contacts closed. You cannot measure this current with a regular digital meter, you may get some indication with an old analog one.
With the OEM 20 gauge wire it took ~50 milliseconds (red trace)
(https://i.servimg.com/u/f62/19/35/15/00/starte10.jpg) (https://servimg.com/view/19351500/9)
I didn't take too much notice of the wire I replaced it with with, at the most 16 AWG but you can see how for a few cents the change in speed was significant. (green trace)
I haven't measured the coils on this starter solenoid but other Valeos I measured are capable of drawing 48-50 Amps at 12 Volts.
After what I found on the Griso I say check the wire size between relay and starter.
If the relay is powered through the ignition switch do yourself a big favour and change that with either an MPH kit or home brewed option.
The time it takes for the solenoid to operate may seem very short but remember this is with a new battery fresh off the tender, it will take much longer if the battery is getting on in years and half flat.
From all the variations in starter wiring over the years it's obvious to me that Luigi is really struggling to solve the Startus interrupts problem. He's not helping himself by not showing how the solenoid coil/s are really wired, the later schematics bear little resemblance to reality.
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Kiwi,
Thank you for the test, this is excellent info. If they used thin 20 ga wire between the relay and the solenoid for the Griso, then you know they did it for the older/smaller bikes.
How convoluted was the path between solenoid and relay for your Griso? I have to brace myself before I go into my bike's wiring; it can be an Alice-in-Wonderland experience between the diagram, the unreliable wire colors, etc.
And...I'm surprised to see you measure wire diameter in gauge. In NZ aren't they Metric?
Joe
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And...I'm surprised to see you measure wire diameter in gauge. In NZ aren't they Metric?
Joe
Yes they are metric but they were Imperial when I did my apprenticeship wire sizes were 1/044, 3/029. 7/029 etc or British Standard Wire Gauge but I live now in Canada where they still haven't decided what to do so I'm more familiar with American Wire Gauge. Probably the only Metric wire I see is on my Guzzi and electrons aren't picky so it gets replaced with AWG sizes.
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Yes they are metric but they were Imperial when I did my apprenticeship wire sizes were 1/044, 3/029. 7/029 etc or British Standard Wire Gauge but I live now in Canada where they still haven't decided what to do so I'm more familiar with American Wire Gauge. Probably the only Metric wire I see is on my Guzzi and electrons aren't picky so it gets replaced with AWG sizes.
Imperial wires sizes, aargh! It's like you're talking about Whitworth wrenches.
For most things in the US it's mixed between SAE and Metric, but wire and shotguns are solidly in gauge sizes.