Honda ntv650 No spark ? & no clue :(

[smokebeer]

Hi guys I am just about at my wits end with my ntv 18 years it never let me down until last winter it blew a fuse and refused to start ever again. I have a big list of parts I have replaced and spent far more time and money on it than I should have I just didn't want to give up on my old friend.

list of parts I've replaced
------------------------------
Honda NTV650 Revere 1997 Ignition Pick Up
Ignition Switch / Lock Unit Assembly
Honda Ntv650 Indicator Relay
Honda Ntv650 Fuel Relay
Regulator Rectifier Honda NTV 650 Revere 1988-1997
HONDA NTV650 REVERE GENERATOR STATOR
Starter Relay Honda NTV 650 Revere
Battery
NTV 650 REVERE MOTORBIKE WIRING LOOM HARNESS
NTV 650 CDI ECU
Honda NTV650 P-V Revere 93-97 Ignition Coil

And new forks/tyres/front disk for its MOT also £100 for a mechanic in a van to come around and look it over and still no luck so if anyone can be of help I would be very grateful but my skills with electrics is poor and replacing the Pulse Generator was my last hope

"Help Me, Obi-Wan Kenobi. You're My Only Hope"

[1198]

Daft question maybe but - plugs?

[spottedtango]

Have you checked the fuse on the starter relay and the block connector is in?


Also main fuse can blow due to a chafed wire Under the clocks behind the headstock.

If it turns over have you checked the contractors at the back of the fuel pump Haven’t corroded together? It’s a lift pump that pumps fuel up to the bowls

Also check fuel pump relay if this has happened as it can take it out.

[Robby]

What are the symptoms? Is it cranking, is it trying to start, anything odd on the clocks?

[jeffyjeff]

Good tips from spottedtango and Robby.
Listen for the sound of the fuel pump when you turn the key 'on'. If the fuel pump isn't working, it needs to be fixed first.
Turn on the key and hit the starter button. The engine has to crank before it can start.
If the fuel pump works and the engine is cranking, remove a spark plug and ground it to the cylinder head (wear a leather glove). Turn the key on and hit the starter. You should see a big fat spark at the plug. Smell for fuel vapors out of the spark plug hole.
The results of these steps will dictate further troubleshooting actions.
____________________
History shows again and again how nature points out the folly of men - BOC

[sickpup]

[Robby]

Assuming it is turning over, you have two tests - does it have spark, and does it have fuel.

Spark - Remove one of the plugs from the head, plug it back into the HT lead. Hold it against the cylinder head and crank the engine. If you see a spark, you have spark.

Fuel - There are drain plugs on the bottom of the carb float bowls, probably connected to thin rubber lines that exit down below the footpegs. Hold a cup under the drain line, open the drain screw, see what comes out. You want to see half a cup of fuel.
If nothing comes out, then the float bowls are empty. The problem is an empty fuel tank, turned off fuel tap (if it has one) or fuel pump not working.
If what comes out is a dirty mix of fuel and water, you have water in the tank. Water doesn't burn.
If you see good, clean fuel, you have fuel.

[smokebeer]

Hi guys thanks for the reply's yes it does turn over better than ever with all the new bits. The old starter would make a nasty clicking noise when the battery was low so they have both been replaced and the 30amp fuse is still good. As for the fuel pump I never heard it in all the time I had the bike and from what I have read it might make it run poorly but not stop the thing sparking ?I didn't replace 4 plugs I didn't think they would all go at once and if you do hold the ht leads you feel nothing no power is getting to them and no spark if you hold it to the engine. I wasn't aware of a fuse under the clocks though I will try and find it.(oops read that wrong the main fuse is fine and the wires were replaced when I fitted a new loom under the seat from battery to ignition)

Again thanks for helping

[jaffa90]

""" ntv 18 years it never let me down until last winter """

You did well (18 years) so why spend all that money and how long do you want the bike to last?
Find out if you have any input voltage to the coils.

[smokebeer]

[jeffyjeff]

https://hawkworks.net/manual/16.html
A quick google search and this came up. Hopefully close enough to your NTV650, if not the same. If I am reading this correctly, and the info here pertains to your bike, there are some diagnostic steps you can do with your multimeter. Follow the flow chart. Hope this helps.

I hesitate to suggest much beyond the factory manual, but this is what I would do in your situation:

1. Find the "spark unit" (ignition module) under the seat on the left side of the bike, might be under the cowl. There is a 4 pin connector with wires coming from the pulse generator, and a 6 pin connector with 4 wires going to the ignition coils. Remove the 4 pin connector.
2. Set your multimeter to AC volts. Touch one lead to the yellow wire terminal and the other lead to the white/yellow wire terminal in the 4 pin connector. To avoid damaging the connection, don't force the leads into the connector terminals just touch them.
3. This will be easier if you can find a helper. Crank the engine over while checking the AC voltage on the yellow and white/yellow wires. A voltage reading (while cranking) shows the pulse generator is good. Do the same for the blue and white/blue wires to check the other pulse generator. These steps establish that the "spark unit" is getting a signal from the pulse generators. If there is no measurable AC voltage going to the spark unit, the pulse generators are bad. If you can measure AC voltage, proceed to the next steps.

Remove the fuel tank. Looks like both ignition coils are under the tank (the rear coil might be under the seat). The front coil is located near the steering head.
4: The rear coil has a 2 pin connector with a Blue/white wire and a yellow/blue wire. Switch the meter to DC volts and repeat the voltage test (while cranking) on those wires. The front coil has spade connectors on it; remove the spade connectors and test voltage on the blue/yellow and blue/white wires.
A. If you have voltage to the coils but no spark, that suggests the coils are bad.
B. If you have voltage going into the "spark unit" but no voltage at the coils, that suggests the "spark unit" is bad.

Could also be a problem with a broken wire in the harness, but these are some tests you can perform to narrow down the location of your problem.
____________________
History shows again and again how nature points out the folly of men - BOC

[smokebeer]

Hi Jeff thanks for the tips I have been using that site trying to find any old post etc that might help. I tried to follow your instructions but the readings I got didn't make any sense to me I don't think I was doing it right but I did go on to test the 6p connectors according to the pic
Bl (+) and G (-), Bu/Y (+) and G (-), Y (+) and G (-)
And the yellow one didn't give any reading the other 2 gave a steady 11. I went and replaced it with the older cdi I had to try their readings and they all gave 11 so I cranked it over and held the right front plug to the engine but no change but for a strange reason I felt the need to test the others as well and WTF all 3 are now sparking its just that front right plug now not working ?I can only think it was the pulse gens I replaced last week made it work but that dodgy cdi stopped it running(I swopped them back and forth so many times now I cant remember which was the replacement). Now I just have to hope its a simple HT lead replacement to get that finale plug working?

One job nears an end another starts some buffoon in a lorry just reversed into my little cb125f knocked it over and drove off pffff I don't think i'm allowed nice things in this world

[jeffyjeff]

smokebeer: I'm sure you are close, since the front left plug is working and both operate off the same coil, the problem is likely in the high tension lead or the spark plug itself. (swap the plugs and see if the problem follows the plug. if not, then HT lead.) Sorry to hear about your 125 . It's really crappy when things like that happen. Hope the damage isn't too severe. All the best, Jeff J.
____________________
History shows again and again how nature points out the folly of men - BOC