No spark from Sporti

[jhmcmath]

Hello All,

 

I have a '97 Sporti that hasn't got a spark on either side. It was running fine 2 months ago and then the last time I went to

start it nothing although it is turning over fine.

 

I'm assuming it's something to do with the coils but it seems unlikely that both would fail simultaneously?

 

Before I go and replace both coils I'm wondering if there is another component I should be looking at?

 

Many thanks for any help.

 

[swooshdave]

No spark on either side mean you should be looking at the ignition and not the coils.

[docc]

With the key on, do you get 12v at the power supply to the coil(s)?

 

There are five relays under the seat?

[jhmcmath]

Thanks guys. Haven't check power to the coils. Not sure how to do that. Remove connector

to coil and test from there? There are 5 relays under then seat.

[swooshdave]

Start with the easiest stuff to access. Relays. Coils rarely fail in pairs.

[docc]

She's likely wired just like an early V11 Sport. The last relay (rearmost) in the row is overburdened (coils, fuel pump, injectors).

 

Can you hear the fuel pump prime when you cycle the Run Switch?

[jhmcmath]

Seems the first relay (to the front) is for the brain, the second for the fuel pump (at least), the middle (which is round unlike the others)

I can't tell, and the last two when removed prevent the headlight from coming on. I swapped around all the relays in the 1,2,4,& 5

positions and all seem to work but the bike still won't start. The fuel pump is definitely priming when the motor cranks. Thanks.

[docc]

Not sure on your relay order, front to back?

[jhmcmath]

I looked it up and the relay order is:

 

1) ECU relay

2) power relay

3) "blinker unit"

4) starter

5) headlight

 

I've swapped around the relays and best I can tell they're good. What would be the next best place to look?

 

Many thanks.

[swooshdave]

http://www.v11lemans.com/forums/index.php?showtopic=14530

 

sport 1100 guzzi ignition sensor site:www.v11lemans.com

 

http://www.v11lemans.com/forums/index.php?showtopic=16937

 

http://www.guzzitech.com/forums/threads/modern-no-start-issue-solution.4908/

[Kiwi_Roy]

The Camshaft Phase sensor or the TDC sensor if you have two.

 

Without pulses from the sensors the ECU doesn't know when to fire or should it turn the pump on.

 

Actually your bike is a little different than the later bikes, here you see the sensor I'm talking about item 59 the Camshaft phase sensor

http://www.thisoldtractor.com/guzzi007/schematics/1996_Sport_1100i.gif

You can check the sensor from the ECU socket 11 & 29 if you unplug the ECU and remove the back off the plug it should read about 680 Ohms according to the book.
This is a great manual for the early fuel injection systems and it's even valuable for the later 2000-2004 bikes

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

The sensors are 7 & 8 on page 2

The TDC sensors are known to collect iron filings from the flywheel, check it's clean.

Many owners have removed the camshaft sensor to fix an oil leak then found the bikes wont fire because the sensor is too far away, it needs to be 0.6 to 1.2 mm according to the manual, measure that by placing a blob of wax or grease on the end, bolt it up then turn over so the engine shaves it down.

 

There are many points in the wiring where you might be losing power, see how vital it is to get power to the red/black wire, if it were my bike the first thing I would do is add a 12V LED to this wire somewhere, perhaps under the seat. You will see it turn on for a few seconds with the key and hear the pump run then stop, as soon as the bike cranks over the light and pump should run again.

 

Something else while I think of it from the schematic it looks as though your bike has those old European pointy fuses clean those up and make sure they have good tension holding the fuse, some owners stretch an O ring around the clips to hold them tight, I like to polish them up by rubbing the points on some rough cloth (my jeans) and smear them with Vaseline

 

If you accidentally put the battery in backwards it will seem to crank over normally but there's a diode inside the ECU that prevents the ECU relay from pulling in. I have replaced a couple of those but your pump seems to prime so the Safety diode must be ok.

 

Just to re-iterate you won't be able to measure power at the coils or pump unless the motor is actually turning over and the ECU sees pulses from the magnetic sensor/s 

[jhmcmath]

Thanks guys. This is all great advice. I'm going to follow up on all these items later day

and get back to you.

[gstallons]

to add to Kiwi Roy's input .If the battery is connected backward , any permanent magnet staring motor will spin . The problem is , it spins in reverse . e.g. the starter spins but not crank the engine . This works on any simple electrical system such as a small engine on riding mowers , etc . Vehicles with more complicated electrical systems allow smoke to come out of places that shouldn't .

  I KNOW .

[fotoguzzi]

maybe dumb but would the motor turn over w/out spark if the kill switch was on?

[docc]

Hello All,

 

I have a '97 Sporti that hasn't got a spark on either side. It was running fine 2 months ago and then the last time I went to

start it nothing although it is turning over fine.

 

I'm assuming it's something to do with the coils but it seems unlikely that both would fail simultaneously?

 

Before I go and replace both coils I'm wondering if there is another component I should be looking at?

 

Many thanks for any help.

Depending on how it has been stored, it may be worth closely inspecting the wiring for rodent damage.