No Spark @ Plug

discussions specific to the 907IE
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DoubleDuc
Posts: 34
Joined: Mon Jul 28, 2014 2:12 am
model: 907 I.E.
year: 1991
Location: Va, USA

No Spark @ Plug

Post by DoubleDuc »

Hey guys: Spring here; fired the bike up about 4 days ago, ran fine. Tried this morning and there's no spark at the plugs (new). I checked the fuses in the modules on the top left front of the bike (I don't know what it's called), checked the fuses near the brain, checked the solenoid, all good; fuel pump cycles.

Any ideas would be greatly appreciated.
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paso750
paso grand pooh-bah
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Re: No Spark @ Plug

Post by paso750 »

was the kill switch accidently turned to OFF position?
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DoubleDuc
Posts: 34
Joined: Mon Jul 28, 2014 2:12 am
model: 907 I.E.
year: 1991
Location: Va, USA

Re: No Spark @ Plug

Post by DoubleDuc »

Hey paso; I thought about that (it may be a faulty kill switch), but the fuel pump cycles and it doesn't cycle w/ the kill switch in the off position.

So, no - it wasn't in the off position. I don't know if this helps or not, but some added info: I use a little starting fluid to try & start it - it will not fire, after releasing the start button it will typically backfire. I'm guessing this is because of the absence of spark and the backfire is compression release; so it probably just confirms there is no spark.

The way I determined there is no spark: I hooked a multi-meter to spark plug (out of the piston cylinder) and ran the starter; no dc voltage. I then put my finger on it just to be sure and no shock.

Thanks again for your thoughts/ideas.
nickta
Posts: 295
Joined: Tue Jul 24, 2012 8:54 am
model: 907 I.E.
year: 1992
Location: Cairns, Queensland, Australia

Re: No Spark @ Plug

Post by nickta »

Check the 12v on the coils. It comes from the same relay as the fuel pump gets its 12v, so most likely it is there, but never hurts to check.

Not much it can be, as it is all very self contained. Check the timing sensors (both of them), make sure they haven't been swapped around (its happened before), check fuel is getting through to the cylinders etc etc. Check all plugs and sockets, and of course, check all the grounds!

I gather all spark has gone from both cylinders? If it has, then it's common to both, which doesn't leave a whole lot.

Cheers.

Nick.
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DoubleDuc
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Joined: Mon Jul 28, 2014 2:12 am
model: 907 I.E.
year: 1991
Location: Va, USA

Re: No Spark @ Plug

Post by DoubleDuc »

Thanks Nickta - yes, no spark in both plugs.
Is (28) Turn Flashing of the schematic (P.79, workshop manual) solely for the turn signals?

Found a post very similar to my problem. In the post, the problem is found to be in the relay modules which are on the upper-left-front of the bike. I'll play w/ them tomorrow; if I keep taking parts off my waiting to be fixed Duc, I'm going to have a pile of broken parts and one bike, lol.

http://forums.ducatipaso.org/viewtopic.php?f=3&t=6854
http://www.12voltplanet.co.uk/relay-guide.html
nickta
Posts: 295
Joined: Tue Jul 24, 2012 8:54 am
model: 907 I.E.
year: 1992
Location: Cairns, Queensland, Australia

Re: No Spark @ Plug

Post by nickta »

Yep, No: 28 is the flasher module. As rule, there is not a lot to them. A bimetallic strip usually, copper and some other metal. As it heats up, it gets to the critical temperature and opens, which opens the circuit, in the 907's case 12 volts, so the indicator goes off. When it cools down again, the circuit closes and the indicator lights up again, etc.

Not unheard of the relay's being dodgy. Finding a relay to replace it is easy and hard at the same time. If you don't want the fuse, any Auto shop has them. If you want the inbuilt fuse, then I wish you luck. There are plenty of the 4 Pin relays (single pin 87) with a fuse in line, but none with a dual pin 87. To make it as close to standard as possible, and still have access to parts, I purchased a couple of in line fuse holders (for the blade type fuses), and wired up the relay bases and fuse holders to suit. There is not a lot of room up where the relays hide, and the wiring isn't really long enough to reach, so some modification is required. It pays for itself the first time you replace a relay!

Cheers.

Nick.
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du907
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Joined: Fri Jul 08, 2005 12:00 am
model: 907 I.E.
year: 1992
Location: Winston-Salem, N.C. USA

Re: No Spark @ Plug

Post by du907 »

Doubleduc,

Exactly what has changed since you started the bike, then 4 days later it would not run? Did you move some wires etc. while doing other tasks?
Best way to run down the fault is to narrow what has changed since it ran well and the next time you started it and it didn't run so well.

Check the plug into the ECU to make sure it is fully seated.
Check the white amp plug zip tied to the frame on the left side just at the rear of the tank. Take the left side cover off and the plug is there on the frame near the spark plug. It's a amp plug with the wire spring retainer clip. If this plug comes loose, the motor will not run (has happened to me). So did the ECU plug working it's way out. Spent two days checking and hunting until I found that. I used a zip tie to make sure it can't back out again.

du907
Bomber
Posts: 25
Joined: Tue May 13, 2008 5:35 pm
model: 907 I.E.
year: 1992
Location: Dumfries,Scotland

Re: No Spark @ Plug

Post by Bomber »

Had a similar fault, bike would turn over but not start.
My Problem was with the two relays with the blade fuses in them, next to the flasher relay.
At some point one of the fuses must have been replaced, but it was a poor fit as it was a slightly different size, so when the bike was running the vibration kept it making a connection, bike ran ok.
When stopped, bike turned over and would not start.
Just in case, its worth a check in case the fuses are a loose fit.

Cheers :)

Gerry
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higgy
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Re: No Spark @ Plug

Post by higgy »

+1 on checking the relay fuse relays can be found at your local fiat recycler


or just replace them with a cheap modern relay...........
Ducati,making mechanics out of riders since 1946
There's no problem so bad that a little fixing can't make it worse! : )
If it ain't broke keep fixin it till it is
88 750
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DoubleDuc
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Joined: Mon Jul 28, 2014 2:12 am
model: 907 I.E.
year: 1991
Location: Va, USA

Re: No Spark @ Plug

Post by DoubleDuc »

Thanks for the support & ideas: I pulled the two relays out & spoke to them softly, put them back in their home and the bike fired up in about 1.5 seconds and runs great - I think the new plugs helped too (w/ the start up efficiency). Replaced the fork seals (took me 3 purchases to get the correct ones even though they were all advertised as 907 friendly), and bled the brakes, which was trickier than I thought (had to have the master cylinder in a certain elevated position).

as paso grand pooh-bah says, "Ducati,making mechanics out of riders since 1946"

I'm working on converting the manual to a word document to make it searchable and contain only English; I'll post it when complete - maybe it'll help someone other than me.
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DoubleDuc
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Re: No Spark @ Plug

Post by DoubleDuc »

Problem occurs again :(
Rode it yesterday - went out today to start it and no spark. I fiddled w/ the relays (again, which 'fixed' it last time) and nothing. I noticed a little acidic green stuff around the insertion point of the relay. I'm going to see if auto parts store has something I can spray in there to dissolve the corrosion.?.

I noticed in my non-working 907 there were two relays, so I tried those - the fuel pump didn't seem to prime as vigorously (I think they were Bosch) and the bike didn't start.

I suppose there's a switch inside the relay that opens/closes upon energizing; maybe the relay needs to be replaced, but I will look for spray first.

Previous posts for suitable replacement parts of the relays:
Part No. R3177P at Advanced Auto
Dyna

Any suggestions?
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DoubleDuc
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model: 907 I.E.
year: 1991
Location: Va, USA

Re: No Spark @ Plug

Post by DoubleDuc »

If I take the fuse out on the two relays & test with voltmeter I have almost 12 volts. Does this mean they are working ok?
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DoubleDuc
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model: 907 I.E.
year: 1991
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Re: No Spark @ Plug

Post by DoubleDuc »

Starting to think it's the outside temperature, as Bomber says his would start but the vibration kept his going, but mine will cut-off and cut-on fine.
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higgy
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Re: No Spark @ Plug

Post by higgy »

a voltage drop of less than .2 volts is the generally accepted standard for that era of technology.
My suggestion would be to check the bottom part of the ignition switch and the kill switch, may be even the internal contacts on the ignition switch as well as every ground and every connector between the battery/regulator, the ignition module and the coils, I think I remember you checked the secondary ignition wires for leaks

any corrosion needs to be removed, chemical solutions are a good start but you need a diamond file or similar fine grain sanding device, too corse and you may as well save your time and buy a new relay...........they are cheap
Ducati,making mechanics out of riders since 1946
There's no problem so bad that a little fixing can't make it worse! : )
If it ain't broke keep fixin it till it is
88 750
90 906
92 907ie
User avatar
DoubleDuc
Posts: 34
Joined: Mon Jul 28, 2014 2:12 am
model: 907 I.E.
year: 1991
Location: Va, USA

Re: No Spark @ Plug

Post by DoubleDuc »

? I messed with it today & now I have spark at the plugs (I don't know what fixed it) but no fire. I tried ether in the intake, in the case there is no gas flow, no fire. I'm almost positive I didn't have spark before as I put my finger on the plug (while starting and kill switch on) and no shock and used voltmeter. Any ideas what would cause it not to fire?
Thanks
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