No Spark When Wet?!?

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Mine had decided to run again after 3 weeks of no spark. I havent dove in headfirst as I dont want to tear apart the bike chasing ghosts, but checked all the basic stuff and found nothing except no spark. Was out of town for a week and returned yesterday with full intent to tear into it. Had a buddy come over with alot more bike building experience than me and before we tore it apart I hit the starter and vroom!!?? I dont trust it at all. May ride it locally today to see if it leaves me stranded.
 
Hello,

Mine did few days ago following:

It was rainy day and I drove to work (one way approximately 45 km). No special things, everything worked normally. Then I let it sit for two days, and when started it, noticed the idle to be a little bit different and tacho showing zero. As the tacho pulse comes from no. 2 cylinder in this older model, the faulty circuit was clear.

When gave it 1500...2000 rpm, the dead cylinder (no. 2) would join the team again, but immediately dropped off when the engine was left idle.

Again... I thought, as it had done this also last year after a rainy ride (that time the problem lasted quite a long period of time and finally disappeared without doing anything).
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First suspected that humidity had entered inside the HT coil, as there were some cracks in the front ones, which I had already sealed last year.

As a routine, checked the pick-ups (renewed last year), plugs, plug caps and leads and exchanged two HT coils to confirm. No efffect. Still the same.
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Therefore suspected the TCI unit area. Last year I took it off one time, but this time wanted to find the reason also, as mysterious faults that appear and disappear are not building the trust towards the bike...

Did some net surfing first and found this link: http://www.venturerider.org/forum/showthread.php?t=10640

It is a link to our fellow VENTURE RIDER'S FORUM, where one guy explains the TCI problems nicely. This was a good encouragement to get further. As we remember, Venture uses basically the same engine as V-Max.

So I took the TCI off and opened it. Cleaned the pins of the wire sockets (6 pin and 8 pin) with brush as a routine. Then before proceeding more, checked it once more again - and zimzalabim - the dead cylinder had been resurrected! So the most likely reason was bad contact with the wire-box-joints. I still let it dry in the sunshine for 2 hours and then put it back. Operation was completely normal. Did not need to do any soldering even.

I like the Venture guy's explanation.
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It suggests that there are quite a few problems with them TCIs, but usually this is not serious.

Just be careful if you are going to open the box. Open all the screws first and be careful not to crack the component plate!
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Regards,

AT
 
OK, rode locally today and it stranded me....again. Started fine, warmed up normally and Rode fine a mile to the gas station and on the way back, it started bogging like it was out of gas (has a full tank). Before you say it, the gas is good. it went about 1/2 mile like this and then died and wouldnt fire again. I pushed it 1/4 mile to the house.

My friend who was riding with me builds drag bikes and he is guessing it to be a rectifier. My Uncle agrees. What do you guys think?

I am unemployed and have a bike payment, so I cant afford to start throwing parts at it if thats not the issue. Is there a way to test the rectifier?

EDIT:
After doing some e-search, It appears that the regulator simply converts the ac power from the stator to dc to charge the battery and run lights and suck. What provides charge to the coils? That has to be where my problem lies as the coils have no spark when it wont start.
 
Is there a way to test the rectifier?
yes - download the Yamaha Service Manual from www.vmaxoutlaw.com - it has full instructions for testing electrical components.

EDIT:
After doing some e-search, It appears that the regulator simply converts the ac power from the stator to dc to charge the battery and run lights and suck. What provides charge to the coils? That has to be where my problem lies as the coils have no spark when it wont start.

The TCI (transistor control ignition) is what sends the pulses to the coils. The pick-up coils is what tells the TCI when to go.
 
Hello Max Power!

I hate to use money for inspections, too. Here is a "free of charge" procedure to check it.

The spark is provided in three (very much simplified) steps:

1) Pick-up coils located under the flywheel cover provide the voltage pulses for the TCI unit

2) TCI unit receives the pulses, controls the release timing and forwards the pulses to the respective ignition HT coils

3) HT coils create the sparks and send them via plug wires and plug caps to the spark plugs which fire the cylinder


First make sure you have good plugs threaded in. Then let the problem occur. Once it's occurred, waste no time and test the pick-up coils and HT coils.

PICK-UP COIL TEST) You need only a multimeter to do this (cost maybe 5 bucks). The pick-up thing is very easy to confirm / rule out. The procedure is as follows:

- prepare multimeter
- remove the seat
- disconnect the joint socket (under the seat) where you can find black, orange, grey, white/red and white/green wires IN CASE OF OLDER MODEL V-MAXES

- if you have newer model, you only find orange and black wires there

- connect the multimeter to the flywheel side (left / lower side) of the socket, and check one by one the resistances between orange-black, grey-black, white/red-black and white/green-black wires (the resistance values should be between 94 to 126 ohms at 20 degr. Celsius (at least somewhere nearby) IN CASE OF OLDER MODEL V-MAXES

- if you have newer model, just test the resistance between the orange and black wires, should be between 81 and 121 ohms or nearby

If the value is clearly out of the specification (or shows no continuity = infinite resistance), the culprit is very likely found. IN THE OLDER MODEL, the meanings of the colours are following:

orange = pulse coming from pick-up coil 1 to TCI unit, giving fire to cylinder 1 (rear left side cylinder)
white/red = pulse coming from pick-up coil 1 to TCI unit, giving fire to cylinder 3 (rear right side cylinder)
grey = pulse coming from pick-up coil 2 to TCI unit, giving fire to cylinder 2 (front left side cylinder)
white/green = pulse coming from pick-up coil 2 to TCI unit, giving fire to cylinder 4 (front right side cylinder)
black = common ground wire to both pick-up coils 1 and 2

In the newer model, there is only one pick-up coil and it's more straightforward.

Bad coils can create this type of problems, because when the wire inside the coil cracks, it may still have contact in some temperature / length. But when the temperature changes, the length of the coil wire changes too, and the contact may disappear - and then return again after the engine (coil) cools down.

When the pick-up coils are clarified and if not guilty, continue to check the HT coils.

HT COIL TEST) Rule out the possibility of ignition HT coils, plug leads and plugs by measurements and / or exchange method.

- First find out, which cylinder(s) doesn't provide spark. This can be quickly done by taking one extra plug and a piece of steel wire. Now disconnect one of the spark plug caps from the plug and connect the extra plug into the cap. Then connect the piece of wire to the plug thread and the other end to the frame bolt or somwhere it gets well grounded.
- Start the engine and see if there is spark in your "extra plug".
- Check each cylinder by turns.
- When the problematic cylinder is clear, conduct a measurement by multimeter for the coil of the problematic cylinder. Check the resistance between red/white and orange wires (primary side). It should be around 2.4-3 ohms. Then measure the secondary side by checking the resistance between coil lead and red/white wire. It should be around 10.5-15.8 kilo ohms without plug cap.

You can confirm the result by removing the ignition HT coil and exchanging it with some other cylinder's coil.
- Then check again, if the problem moves with the HT coil or stays in the original place.
- If it stays in the original place, go ahead and check the TCI unit
- If it moves with HT coil, measure the values again and try some different plug lead and plug caps with the coil.


When the HT coils are clarified and if not guilty, continue into TCI.

- First disconnect the joint sockets, both of them, from the TCI unit. Then carefully use suitable brush and maybe some electrical circuit cleaner liquid and brush the connectors clean from the unit side and from the socket side.

- Connect the sockets again into the unit and try if the problem went away.

- If it still exist, see the TCI thing here: http://www.venturerider.org/forum/sh...ad.php?t=10640

Note that the front cylinder HT coils are crossed. Left side provides spark to right side cylinder and vice versa.

Hopefully you can find it out soon!
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Cheers,

AT
 
max power,
You've gotten some fantastic advice here! Let me know if you want to try the diode replacement and I'll send you a working used one for free. After reading the thread on the TCI, I'm going to overhaul mine the next time I get a chance.
 
Fixed. :eusa_dance:

Bad fuel pump power connection. :bang head:

FML. lost a whole month of the riding season. Oh well, it gave me time to finish my remodel project and I will make up for it by riding my ass off.

Thanks everybody.:icon_jook: You ROCK!
 
max power, that's great news! I'm really glad you found the problem. Electrical gremlins can be a real pain in butt! Happy riding.:punk:
 
Fixed. :eusa_dance:

Bad fuel pump power connection. :bang head:

FML. lost a whole month of the riding season. Oh well, it gave me time to finish my remodel project and I will make up for it by riding my ass off.

Thanks everybody.:icon_jook: You ROCK!

Congrats! Alway good to hear a happy ending.

What is FML??
 
Who do you turn to when you need the definition of a dirty acronym? Garrett!! ROTFLMFAO!!:rofl_200:

oh c'mon that was an easy one haha!

theres an FML website i guess too, haven' thad time to check it out yet..

hopefully as funny as failblog
 

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OK, I lied. Rode 150 miles Saturday, got home, washed the bike, started right up and idled. Shut off. Dried off. Went to start to pull into the garage and no spark. Next day. No spark. FML!
 
max, have you had a chance to try any of the other stuff yet? The only thing that sucks more than an electrical problem is one that you thought you had fixed! Mine reared it's ugly friggin' head 350 miles from home.:bang head:

Thankfully I think mine is good now, and it's earning my trust back. I have to force myself to remember that anything mechanical can and will hose you at some point.
 
So after 16 days of not touching the bike other that the occasional lighting of the starter switch to find that it still wont start, I finally find time today to tear into it. The first thing I do as always, is hit the starter. Guess what? It starts right up. :bang head: How do i find the problem if it works?
This has gotten beyond frustrating.

I think I found how to test the TCI in the manual, but where the hell is it? Does my issue sound familiar to anybody? Really scratching my head at this point. :ummm:
 
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