FJ1200 wont start just huge backfire bringing neighbours out LOL

[hook line n sinker]

ok look it was cold this morning i took the car to work i didnt realise it would upset the old girl but it has turns over stinks of petrol and gives huge and i mean huge backfires like friggin bombs going off lol , neighbours come have come out in the street its that loud . Been raining today and she has had a soaking . Obviously im thinking flooded and damp= electrics just had new battery . Are fj1200 s known for flooding ? is a 87 has 80,000 miles on clock been ratted with straight through exhausts pretty much hasnt been jetted up in the carbs though could this be causing the problem fouling plugs ? Notice the lights dim a lot on tickover is this normal for FjS

Any help please

[Pat Conlon]

You talked about this back on Feb 11th, the bike isn't going to fix itself.
You have either a
1) stuck float causing the flooding, or
2) debris on the float needle seat keeping the needle from closing or,
3) Leaking float needle O rings causing the flooding.
4) or all of the above.

Unless you stop talking about it and take some action to fix it, you will experience the wonderful phenomea of "hydro locking"

You have been warned.

To start, if you can't get your FJ out of the snow and rain, why don't you get your FJ under a cover?  That poor bike.

[hook line n sinker]

No No No the bike started and ran sweet after the battery got replaced , came home from work and turned her over and these symptoms have started . So not the same as the other day . Am wondering if the straight through exhausts have affected the carburation though seemed to be running fine yesterday .

Should the bike be keeping the battery fully charged as i notice that having just removed it again and put it on charge the charger is telling me its not fully charged , was wondering if this is what is killing my batteries ?  Alternator ? What should a alternator be knocking out on a fj ? Are they prone to fail on Fj1200s

[Steve_in_Florida]

What should a alternator be knocking out on a fj ? Are they prone to fail on Fj1200s?

As I recall, the recommended maintenance interval on the alternator brushes is at either 60,000 or 65,000 miles. Yours has 87,000 miles, so it might be due.

If a battery load tester registers less than about 12.5 volts at 2,500 RPM's, then the alternator is DEFINITELY suspect. At this engine speed, the alternator SHOULD be outputting around 14.2 volts.

Borrow the use of a load tester, and report your findings.

Steve

[Pat Conlon]

 Ok gotcha, no flooding of gas, no gas puking out of the carbs but backfire on startup.
Rain soaked bike. Possible water caused misfire? Water shorting out one or more of your spark plug leads?
Water shorting out one of the coil signal or power leads? Water in your electrical connectors?
When the bike is turned off with your new battery connected is there a current drain on your new battery?
Put a mulitester between the positive wire and battery terminal and see if there is a current reading on the scale. In the wet environment you could have developed a ground fault or short.
Your new battery should last longer without needing a charger hooked up to it.

[ribbert]

Some here have answered your question on the assumption that by flooding you mean leaking fuel, they are entirely different things.
The general use of the term flooding is when the motor gets too much fuel while cranking to fire resulting in wet plugs and the associated smell of fuel. This will also happen if there is no or insufficient or irregular spark or an excess of fuel entering the motor.

If it ran fine yesterday, got soaked, won't run and backfires today it seems pretty straight forward.

The FJ's electrics are well protected from water but if your bike has been ratted it has probably lost a lot of that protection.

If this came through my door with the circumstances you describe, I would blow off all the electrics with compressed air (or leaf blower) and spray liberally with WD40.

That would be my starting point.

Think about it, if it ran fine with straight pipes yesterday, what changed on the pipes overnight? Nothing!

Noel

[andyb]

There's water in the electrics. 

That said, it also didn't run well a few days ago either, if you're on stock carb settings but with an obnoxious exhaust.  Probably not making it any easier to start, water or not, and leaving power on the table by not getting the fueling right.

[Mark Olson]

beware the hydrolock , the 86/87 models are famous for it. 

your rods will bend.

[pdxfj]

I'm of the electrical issue line on thinking..

Had the exact same thing happen after doing an oil change and pinching one of the coil trigger lines behind the oil filter housing.  Huge backfires..

You say it's been out in the rain.  I would pull the timing cover off the lower left side of the engine and see if water has made it past the gasket.  From there follow the trigger lines up and see if any of the connectors got wet.