White Smoke While Trying to Crank Engine

[YL82]

My ride is a 1976 Yamaha XS650C.

I recently installed a Pamco, a new advance unit, new advance rod, new Iridium spark plugs and spark plug wires and the high output coil. I'm no mechanic, but I did the install myself in a methodical manner.

The bike started up just fine , but I had to abort setting the timing since my fuel petcocks were leaking terribly. I then removed the fuel tank, removed the non-vacuum petcocks and rebuilt them. I then added Visu-Filter Slimline fuel filters (with sintered bronze elements) and did some other unrelated work.

After I reinstalled the tank, I hooked the fuel petcocks back up and refilled the gas tank with about 3 gallons of gas.

I decided to charge the battery since a few weeks had gone by since I had installed the Pamco.

I have a Battery Minder (Model 12117). See attached image.

I recharged the battery overnight.

One thing that I did do was to turn on the switch to ensure that I was in neutral. I left the switch on for a minute or two (while the battery charger was doing its thing with the battery still installed and wired up in the bike).

Starting: Starting was difficult and I had to push Start button numerous times. I noticed a little white smoke coming from under the fuel tank on the right side. I removed the fuel tank and checked out everything. Didn't see anything amiss.

I then tried again to restart the bike and got it started and let it run while adjusting the idle and allow the engine to warm up. At this point, I revved up the engine some to keep it going and noticed a clanking noise - which I think was mis-timing.

I then turned off the engine, then tried to restart the engine and a profuse amount of white smoke came out from right side below tank.

I noticed that the Pamco (cover was removed for setting timing...) was hot and that the advance unit cover was very hot.

Have I somehow fried the Pamco? Could I have overcharged the (new) battery causing a problem with the ignition system? Did turning on the switch during charging have anything to do with my current dilemma? Where the hell is the white smoke coming from exactly?



I've tried to provide a detailed timeline of the things I did along the way, so hopefully someone can figure out what I did WRONG and help me determine how much damage I actually did and what parts I need to replace.

Notes: At no point did I disconnect a spark plug... Pamco is well grounded to frame... I did perform the Pamco Pete test for free movement of the advance mechanism and the weights snapped back fine...no binding...

More info: There is a possibility that the 5 gallon gas can that I used may have had some water in it. The plastic can had been sitting empty outside for a few days and had the yellow cap installed over the spout. I took the can to the gas station and pumped in 3 gallons. Perhaps condensation had formed in the can..? A post I read about white smoke led me to this possibility. Water in the fuel tank can cause white smoke to be emitted from the carbs.

Thanks!!

 

[5twins]

The white smoke could be from backfiring through the carbs which could just be timing off a little. If you can get it to run, put a timing light on it and dial the Pamco in first thing.

 

[pamcopete]

YamaLovin76,

Wow...you've got a lot going on here. Battery charging, white smoke, hot parts, leaking pet cocks, engine noises, bad gas...I would suggest the following:

1. Disconnect the PAMCO and coil from the bikes wiring.
2. Connect the PAMCO and the coil to an external battery.
3. Do not turn on anything on the bike.
4. With power to the coil and the PAMCO from the external battery, kick start the engine.

If the engine fires up, then you have eliminated about 1 of the 30 problems you are juggling and can then proceed methodically to solve the other 29.

 

[crashcourse]

This may not be your problem, but last time I had lots of white smoke it was because fuel had leaked past the carbs, past the rings, and into my engine oil, which then leaked back into the combustion chamber. Easy way to eliminate this as a possibility is to check your oil and see if there is way too much of it (more than you ever put in). If your oil level is higher than normal and it smells like gas, you've got to figure out why there is gas in your oil, which is probably because of a misadjusted carb float.

Now, I know that may not relate to your problem, but if it does, it is an easy fix.

 

[YL82]

Thanks for the replies, All!

I had to walk away from the carnage for about 24 hours...

When I re-installed the fuel tank and went to reconnect the fuel petcocks, I noticed on the right fuel petcock (side that white smoke was coming from) had a layer of what appears to be rust all over it and the plate that connects both of the diaphragm covers was also covered with rust or some kind of brown residue, perhaps from the white smoke. Perhaps the attached images will help pinpoint the problem(s). You might notice atop the diaphragm cover that there is a white residue (little white dots) also likely leftover from the smoke...

Starting to think its more of a fuel system issue than ignition system issue, but my confidence in knowing WTH I'm doing is waning quick.

At any rate, I've drained the fuel tank via the fuel petcocks and drained the carbs and will add uncompromised gas. Then follow the advice given by you kind folks...