Electrical and starting problems.

[jimathyy]

Following on from the many issue i have had with the bike, in essence, having owned for 8 months, only had running for 1-2 out of that. Depressed.

Anyhoo, had issue with electrics, assumed was poor connection from reg/rec as wire was loose, so taken off, put on new connector and charged battery.

No start.

(a history of poor running / missfire)

Got running, took out (in the rain) and it developed same issue. As light were on, i feel that the battery has died. Now this can only be buggered battery / reg/rec as far as i can see, as had no issues in recent weeks. Have, however left standing for most of the summer.

Today's problem.

Couldn't start her, so connected to car (off). Engine turns, but only occasional firing. HOWEVER, most of the firing is more like a loud bang, and not a "starting" sound. Occasionally sends bang the "wrong way" out of the carbs to the underside of the tank.

What could cause this? I've tried throwing some fuel straight into carbs, nothing. it just won't catch to go.....

Tried some carb cleaner, and some starting stuff from halfords, but still no joy. I have spark and fuel at both cylinders, and am now a bit lost as to where to look.

PLEASE HELP, I'M GOING MAD!!

[Geodude]

If you have a multimeter at hand it might be worth giving this electrical fault finder (http://www.electrosport.com/media/pdf/fault-finding-diagram.pdf) a try. Not sure about the banging from the carbs but have a free bump for your question :)

[Serdna]

I don't know about your previous problems but maybe you need new spark plugs. Going out in the rain can throw water on the front plug causing the bike to really missfire, running just on 1 cylinder. When i took mine out the front plug was rusty.

The sparkplug problem can be fixed by fitting a fender extender on the front mud guard.

Good luck!

[Geese]

Didn't TAm have a similar problem?

wasn't it due to some mouldy wire?

[Taipan]

Doesn't sound dissimilar to water in the tank. On my old curvy SV the tank drain had rotted through and when it rained i'd get water seep into the tank. Might be worth checking your tank drain is okay?

http://forums.sv650.org/showthread.php?t=142806

[TamSV]

Bloody hell, you've not had much luck mate.

Water in the tank is worth checking if your problems have been linked to wet weather. Costs nowt too, which is a bonus. Worthwhile giving the carbs a good strip and clean if you haven't done so already.

Back-firing through the carbs though? :eek: What's the history of the engine? (I think you replaced it didn't you?). Is there a possibility that the timing's been mucked up? Was the replacement motor intact with heads and cam chain tensioners etc all in place?

I seem to remember you've also had a few electrical problems? If you haven't got a multimeter then get one and get systematic checking everything. Don't keep chucking parts at it until you're sure you've got to the bottom of it.

If it was me, I'd be doing the following;

1. If your battery's been run flat a few times or left standing, check it's still holding a charge. If not, get a good un in there.
2. check charging system, leakage etc with multimeter. Check your earths and connections are all nice and clean.
3. strip, clean and set-up the carbs
4. drain some fuel out the tank and make sure there's no water in there
5. check the timing (and while you're in there you might as well measure valve clearances)
6. Put it back together. Start it. Do a celebratory burn-out. :)

You've chucked enough money at this bike now. All the checks above are free. Keep us updated with your findings from the above and someone might be able to narrow things down for you. I'm sure we'd all like to see you resolve this.

[jimathyy]

Hi guys. Today I have drained fuel, nothing abnormal. New fuel anyway.

Cleaned carbs and opened rear one up, no gunge etc.

Not yet looked at the timing, am assuming it's true cause it was running sweet.

Have tried turning over, nothin but a few loud bangs, but havn't pulled the fuel through yet I think, more attempts tomorrow.

I DID however find a kink in the fuel expansion/overflow line. Maybe, and gopefully the issue!

Battery seems fine, can't do all checks though without it running......

Further updates as and when.

For additional info, this is the 2nd engine, and it came complete and ran well, when it was running. Had nbo end of bloody problems! Aarrgg! The wife is most certainly not happy!

Anythin else I should check before I put mucho effort into cranking her over?

J

[jimathyy]

Today's update......

1. Had a small amount of exposed wire on the main -ive to the battery, so have taped up, melted plastic on exhaust in the past, but it's never cause any issues before.....

2. Had a loose -ive on the thermostat. Put back in place.

3. Ensured all other wiring is in the right place.

4. Ensured that fuel getting to carbs, it is.

5. Double checked battery. Reading 12.7 v as it stands unplugged.

6. Removed spark plugs and cleaned, warmed and wire brushed. Good spark when tested against frame.

7. Went to start with half choke. Nothing.
7.A. Full chock. Nothing.
7.B. No choke. Nothing except 2 backfires.

8. Pulled out some hair.

9. Tried again. Had a fag. Tried AGAIN. Nothing.

10. Came and logged on.......

Any ideas guys? Might have to get to a garage, but don't want this to beat me, and can't really afford the £60/hour labour!!!!!

J

[muzikill]

When i had a starting problem (injected model) someone suggested smelling into the area where the fuel goes to be ignited if it didnt smell of fuel then to try scooshing some sure start into it and quickly firing the engine up which it did. I ended up having to send the injectors away to be cleaned. Ok so you have the carb sv, but it was this 'thinking out the box' type advice that eventuially resolved my issue.

[jimathyy]

It's defo got fuel in carbs. Is it worth dunking a load of fuel straight in the top? I have some easy start too, but not really too sure how to use it...... :(

[muzikill]

Someone have experience in checking this?. Id be concerned dumping fuel in especially,if your engines going 'bang'. The method I used allowed the engine to turn over enough to know the injectors were the problem as the sure start was like spraying a fuel mist straigh t in rhereby emulating the injectors on a pointy. So your maybe looking to emulate what the carbs are supposed to do?

[Geodude]

Dont know if you read my charging problems thread (http://forums.sv650.org/showthread.php?t=164281) as my battery kept going flat and i replaced reg rec and battery for new, anyway below is a quote from my thread and how i fixed it with i bit of wire :mad: HTH

Right todays adventure may have sorted it but also showed how daft i maybe at the same time..

Ignition off battery 12.7
Idle lights on +14v
Rev 5k lights on 13.8 to 14v

This was achieved by running a wire from the black wire on reg/rec to the -ve on the battery so it looks like it was a bad earth or wire somewhere :oops: Is it safe to keep this wire permanently attached now as it seems to work?

Yeah just make it neat, do same to +ve, wires from reg-rec to ring terminals on battery. Good idea to put a fuse on +ve.

[Taipan]

Doesn't sound dissimilar to water in the tank. On my old curvy SV the tank drain had rotted through and when it rained i'd get water seep into the tank. Might be worth checking your tank drain is okay?

http://forums.sv650.org/showthread.php?t=142806


Did you read the above linked to thread? For the sake of 10 minutes I'd take the tank off and drain the fuel out into a bucket. If you've got water in the tank you;re going to draw water contaminated fuel through and when I was doing that I had very similar symptoms to yours.

Also check the rubber plug is still on the inlet vacuum take off.

[jimathyy]

Fuel checked and ok.

Rubber plug?

[tim8061]

If it's backfiring that sounds like an ignition problem - maybe the crank position sensor has failed?

[jimathyy]

Where would I find that? I have had the side off recently to change the starter clutch, could I have moved something errornously?

[Biker Biggles]

Fuel checked and ok.

Rubber plug?

One thing that could cause your problem is an intake air leak somewhere.There is a rubber plug that seals an open tap on the inlet manifold which needs to be in place.Also check the carbs are fully seated on the intake rubbers with no leaks,andthe aibox sits properly on the carbs.There are two breather pipes which run from the crankcases to the airbox.They need to be in place too,though I doubt they would cause total non running if adrift.
When you cleaned the carbs did you take out the choke plungers?And did you manage to drain the fuel out of them?Both a good idea if stuck on a problem.