(Solved!) Had to get a jump start from roadside assistance; starter motor not cranking after a chilly night; intermitent issue?!

[MartyNZ]

On 11/16/2021 at 1:00 PM, p6x said:

...when I pushed the started button, the light's intensity diminished, but the starter motor did not crank. Tried a few times, nothing. Tried again, the starter cranked immediately...

I had these symptoms on my '03, after the bike sitting unused for too long with the rear drive out. I replaced the 5 pin relay in the forward position, and now all good.

This time I binned the relay, instead of putting it in with all the spares of doubtful function in the monkey paw trap.

[Kiwi_Roy]

The early VIIs like my 2001 Greeny had the start relay powered direct from the battery via fuse 5, (the start relay 30 terminal was always alive, it never had a problem cranking but then a couple of years later the factory changed the wiring so that the start relay is fed from the ignition switch via a switched fuse, thats when things went to hell in a handbasket.

Pull out your start relay and see if the 30 terminal is alive with the key Off - Good

Do you have to turn the key On - Bad

 

MartyNZ said

"I had these symptoms on my '03, after the bike sitting unused for too long with the rear drive out. I replaced the 5 pin relay in the forward position, and now all good.

This time I binned the relay, instead of putting it in with all the spares of doubtful function in the monkey paw trap."

Another problem with the VIIs the relay bases corrode or build up resistance between the pins and the socket, if you wiggle the relay in the socket it restores the connection somewhat, you can also remove the contacts from the base and squeeze each connector a little to improve the tension. I always applied a little Vaseline to my relay pins, there is probably something better. Typically the wire from the relay to the solenoid is too light a gauge, the factory don't size it for 50 Amps.

Because the starter solenoid draws so much current while it is pulling the gear into mesh  resistance between the battery and the solenoid is critical, 0.2 Ohms is right at the ragged edge. Calculate how much Voltage drop you will get at 50 Amps.

Most other guzzles can be fixed by simply providing a new permanently On feed to the start relay however your VIIs use the normally closed start contact to power up the headlight relay so its a little tricky, lately I have been suggesting an additional relay to solve this problem.

I can see some of you going "50 Amps, what's he smoking" so do a simple test, measure with your Ohmmeter from the spade connector to chassis (don't forget to subtract the lead resistance) Calculate 12 V / Resistance to get Amps.

Ohmmeters are not particularly good for measuring low resistance but see what you get.

[p6x]

17 hours ago, docc said:

Looks like you are pushing the start button about once per second ten times. What happens if you turn the key on and wait ten seconds before pressing the start button ?

It takes longer....

I checked multiple scenarios, including swapping relays, switching on and off (in case it would be an ignition switch issue), balancing the engine (putting the bike in third gear and moving).

Repeat start button pushes always yield.

Note, the colder the temperature, the higher the number of pushes. I have other videos with temperatures around the 50F where it takes only two attempts to get the crank.

Why would this issue only occur when it is cold, and never when it is warm? I never had a start problem when the ambient temperature was its usual Texas style self. As said before, I experienced the same crank issue on my 504 Peugeot. A few taps on the solenoid would solve it.

[p6x]

17 hours ago, Kiwi_Roy said:

No, its not the solenoid, you are losing Voltage across the ignition switch and wiring, you can see it in the lights, there's not enough current to pull the battery down, its dropping across the resistance. I'm willing to bet if you took a jumper wire from the solenoid spade connector and touched it on battery Positive it would start every time no matter how cold. The starter solenoid is designed to draw 50+ Amps but its hampered by the switch and wiring.

It's also possible the ignition switch has a higher resistance because the grease in it is cold, cleaning and replacing the grease with Vaseline would be a temporary fix.

I have written down all the suggestions.

I am going to get to the bottom of it.

How would you explain that repeat attempts eventually yield? joule effect?

[p6x]

On 1/20/2022 at 10:12 PM, PJPR01 said:

Sounds like the problem that the older Land Rovers (Defenders, Series vehicles) have with the starters.  Frequently solved by hitting it on the casing with a hammer to free it up and then they start right up.  Quite a few folks in the HLRC (Houston Land Rover club) have experienced this regularly.  Not that I'm recommending the same solution here, but is the starter an original one or does it look it's been replaced at some point?  

Presumably all of the battery connections have been tightened down sufficiently as well.

Just another thought on this...do you by any chance have a Lithium battery on the bike.  The symptoms can be exactly the same in cold weather...where the battery has to "wake up" a bit.  I've seen this on my Shorai from time to time...

This is exactly what happened with my 70's and older cars. I did state it as a possibility here too.

I have a conventional battery installed in my bike. New from April 2021.

I have worked with Lithium batteries a lot during my professional endeavors. in the 80's, a long time ago. My company worked with a major battery company: https://www.leclanche.com/ to custom design batteries for our application.

I would never put Lithium in my bike for multiple reasons, no matter the perks.

[p6x]

9 hours ago, MartyNZ said:

I had these symptoms on my '03, after the bike sitting unused for too long with the rear drive out. I replaced the 5 pin relay in the forward position, and now all good.

This time I binned the relay, instead of putting it in with all the spares of doubtful function in the monkey paw trap.

Replacing the relay in position 1 was my first shot at solving the problem. No go.

[p6x]

On 1/20/2022 at 11:03 PM, Kiwi_Roy said:

When you press start does the starter clunk in then just refuse to turn i.e. can't generate enough torque.

Try scraping the battery terminals and especially where the main ground connects to the gearbox.

Measure the Voltage at the starter to chassis while its trying to turn, anything over 9.5 should spin it over.

 

Or do you just get a quiet click from the relay? The lights going dim indicate low Voltage, possibly lost across the ignition switch., Measure the Voltage on the spade connector relative to chassis while you press start, if the starter is not cranking you should see 12 Volts.

Keep in mind the solenoid is designed to draw 50 Amps while it engages the starter and it's not even turning yet. As Guzzi feed it through the ignition switch you are lucky to get even half the design current so why be surprised when it doesn't work?

Finally try hot wiring the solenoid from the spade connector to the battery positive, thats how it is supposed to engage the starter, with a loud clunk. Thats the most direct way of operating the starter, if it doesn't engage and crank its a starter or battery problem (including bad connections)

I posted a sketch here

https://wildguzzi.com/forum/index.php?topic=113795.0

You only hear the relay underneath the seat. Absolutely no sound from the starter. This is why I suspected the Solenoid.

The battery terminals are shiny. No sulfate, nothing that could create a resistance.

I will get to the bottom of this issue next week.

[Tomchri]

1 sensible thing to do, install a strong extra start relay. Explained by K Roy and others here. I installed a 70amp relay.

 Cheers Tom.

[Kiwi_Roy]

19 hours ago, p6x said:

You only hear the relay underneath the seat. Absolutely no sound from the starter. This is why I suspected the Solenoid.

The battery terminals are shiny. No sulfate, nothing that could create a resistance.

I will get to the bottom of this issue next week.

Its probably not the solenoid, the wiring is not delivering enough current. You only hear the relay under the seat because the solenoid is not getting enough current to start it moving. (I should add the solenoid plunger could be stuck if its gummed up with grease, I just use a couple of drops of 3 in 1)

Do the simple test of hot wiring the solenoid from the battery, if it's easier take the starter relay out and touch a wire from the 87 contact to the battery Positive. You don't need the key On to try that but do make sure the bike is in neutral. If it cranks with the jumper there is no reason for it not to crank when its wired right.

You might find its harder to get started in cold weather, I put it to you that the grease inside the ignition switch is much stiffer holding the contacts apart, try flicking the switch back and forth a few times to see if it improves..

The real fix is to provide the start relay with a direct feed from the battery, not quite as easy on the Spine frame bikes because they use the normally closed start contact to power up the headlight relay, If you power up the 30 terminal the headlight will go when the key is off. There are several ways around this but i'm now in favour of adding another relay beside the solenoid triggered from the original trigger wire. The relay contacts go between the large positive post and the spade connector.  A 20 Amp in-line fuse can be added between the positive post and relay terminal 30.

p6x, its Startus Interuptus in this case (insufficient solenoid current) but when you clean the battery terminals don't forget the main ground at the gearbox and always use a little Vaseline to keep the contacts clean free from corrosion.

Update,

p6x, I suspect it's worse when cold because the grease inside the ignition switch is stiffer trending to hold more tension off the contacts, if you take the switch apart you will see this. Fresh Vaseline is much softer so it can flow out of the way, You could remove all the grease and leave it dry but then the contacts would vanish in no time flat. Electricians have been using Petroleum jelly aka Vaseline on sliding contacts for 100 years. Its not just your VII that suffers from this ailment, The Brevas large and small are well known for it, later 8 Valve CARC bikes, the earlier 4 Valve CARC bikes had direct wiring. The modern bikes like V7s don't seem to be suffering yet but I suspect that's just age, they all have a similar 2 coil solenoid wired through the switch.

 

"Moto Guzzi, making Electricians out of riders since 1921."   

[p6x]

On 1/22/2022 at 1:17 PM, Kiwi_Roy said:

Its probably not the solenoid, the wiring is not delivering enough current. You only hear the relay under the seat because the solenoid is not getting enough current to start it moving. (I should add the solenoid plunger could be stuck if its gummed up with grease, I just use a couple of drops of 3 in 1)

I will check.

 

Do the simple test of hot wiring the solenoid from the battery, if it's easier take the starter relay out and touch a wire from the 87 contact to the battery Positive. You don't need the key On to try that but do make sure the bike is in neutral. If it cranks with the jumper there is no reason for it not to crank when its wired right.

What wire size do you recommend? I do not have any spare wire, and I will need to go and purchase it specifically.

You might find its harder to get started in cold weather, I put it to you that the grease inside the ignition switch is much stiffer holding the contacts apart, try flicking the switch back and forth a few times to see if it improves..

Flicking the switch on and off I have tried initially. It does not improve the number of attempts to get the crank. I am now doing the easy way. Without turning the key.

The real fix is to provide the start relay with a direct feed from the battery, not quite as easy on the Spine frame bikes because they use the normally closed start contact to power up the headlight relay, If you power up the 30 terminal the headlight will go when the key is off. There are several ways around this but i'm now in favour of adding another relay beside the solenoid triggered from the original trigger wire. The relay contacts go between the large positive post and the spade connector.  A 20 Amp in-line fuse can be added between the positive post and relay terminal 30.

I am going to start with the easy fixes.

p6x, its Startus Interuptus in this case (insufficient solenoid current) but when you clean the battery terminals don't forget the main ground at the gearbox and always use a little Vaseline to keep the contacts clean free from corrosion.

Will do!

Update,

p6x, I suspect it's worse when cold because the grease inside the ignition switch is stiffer trending to hold more tension off the contacts, if you take the switch apart you will see this. Fresh Vaseline is much softer so it can flow out of the way, You could remove all the grease and leave it dry but then the contacts would vanish in no time flat. Electricians have been using Petroleum jelly aka Vaseline on sliding contacts for 100 years. Its not just your VII that suffers from this ailment, The Brevas large and small are well known for it, later 8 Valve CARC bikes, the earlier 4 Valve CARC bikes had direct wiring. The modern bikes like V7s don't seem to be suffering yet but I suspect that's just age, they all have a similar 2 coil solenoid wired through the switch.

Everything leads back to that ignition switch. I don't suppose Lithium spray through one of the port could help, could it?

 

"Moto Guzzi, making Electricians out of riders since 1921."   

 

[Kiwi_Roy]

If you find the spade connector on the solenoid loose thats a sure sign it has been overheating due to resistance. The metal has annealed loosing tension. Replace the spade connector and don't forget to apply some Vaseline to the wire before you crimp it on.

On many Guzzi's this wire from the relay to the solenoid is too small, you can easily lose a Volt and 10 Amps at the solenoid right there, a 16 gauge or metric equivalent is about right.

On my 06 Griso I up-sized this wire one size, the time to engage the starter dropped from 50 milliseconds down to 15 

[Kiwi_Roy]

On 11/16/2021 at 5:30 PM, p6x said:

@docc I read that thread, and all the others that treated of that subject. And there are many throughout the years.

From K-Boy, I got that the starter load is carried through the switch via these flimsy poles on a plastic tab.

However, on the LeMans, it is not a 15 minutes job. There is no easy access to the two screws that hold the contactor switch.

Today, the starter cranked right on point.

I am trying to make sense of what made the jump start successfully the other day. If the poles were not properly in line, the starter should not have cranked. Unless of course, the jump added enough CCA that the poor alignment carried enough Amps.

 

No, the starter load is not carried through the ignition switch, just the solenoid load is. the starter motor itself will draw 150 - 170 Amps

I don't believe the switch is rated at any more than about 10 Amps, I cannot find the specs.

The solenoid has a massive job to do, it has to slide the gear all the way across to engage with the ring gear, I think it takes something like 30 Amps minimum to do that, but the solenoid is designed to pull 50 Amps so why not use all that power.

Power = Current squared x resistance, the heavy current coil is 0.25 ohms

At 30 Amps the power draw is 30 x 30 x 0.25 = 225 Watts

At 50 Amps the power draw is 50 x 50 x 0.25 = 625 Watts

Which do you think might work better?

This high current to the solenoid only flows for a fraction of a second, as soon as it starts to crank the heavy coil is effectively switched out and the light coil just draws ~ 10 Amps

 

I often see an owner say the bike cranks ok in warm weather but plays up when its cold, there's a very simple explanation for that. The ignition switch has sliding contacts and sliding contacts need to be lubricates or they will quickly wear away. When it is cold the lube becomes much stiffer than normal so it tends to take tension off the contact point therefore the resistance increases to a point that there is insufficient current flowing to get the solenoid moving 1/2 an Ohm is too much. Petroleum jelly aka Vaseline has been used for over 100 years to lubricate sliding contacts. As it ages the jelly loses some of the more volatile components this also makes it stiffer.

I think if you were to clean and replace the lube in the switch every 4 or 5 years it would probably keep working ok but I recommend bypassing the switch altogether and give the solenoid the current it was designed to operate on i.e. 50 Amps. The easiest way to do this IMHO is to add another relay next to the solenoid using the original trigger wire to feed the new relays coil

 

If you look at the schematic for a 1999 VII Sport you can see that the start relay on that model doesn't get its power through the ignition switch, instead it gets it from the battery through a fuse the one I had never hesitated to crank all the time I owned it. Another bike that got it right was the early CARC bikes, they also have a direct feed where later ones hav extra relays and still suffer.

[p6x]

@Kiwi_Roy

I got it now; I understand better when I look at the drawing below.

The starter motor is directly connected to the battery via 11.

In my case, if I keep depressing the starter button for more than one second when the starter does not crank, I blow the 15 amps fuse. Repeat starter button presses, spaced of about 1 second eventually yield without turning switching off. Do you think it eventually cranks because repeat coulombs flow warm up the contacts?

 

 

[docc]

3 hours ago, p6x said:

Do you think it eventually cranks because repeat coulombs flow warm up the contacts?

 

Or it warms the battery. This is why I suggested simply turning the key on for ten seconds before attempting to start.

Simple to see if that makes any difference.

(Kiwi_Roy is totally on the mark that these are the exact symptoms of Ignition Switch Startus Interuptus. )

[p6x]

On 1/26/2022 at 10:35 AM, docc said:

Or it warms the battery. This is why I suggested simply turning the key on for ten seconds before attempting to start.

Simple to see if that makes any difference.

(Kiwi_Roy is totally on the mark that these are the exact symptoms of Ignition Switch Startus Interuptus. )

We are going to find out (I hope) I asked the Doctor to check it.