White smoke/oil in exhaust - help!

[AirsoftNY]

White smoke/oil in exhaust - VIDEO

Hi all,

I'm getting a pretty good amount of white smoke from my left exhaust. There is also a little oil dripped out of the area where the muffler joins the header pipe. That cylinder is also idling erratically now.

This is a new condition, it ran great about two weeks ago, so I have changed nothing.

I'm bummed. I'm guessing that all three symptoms are related, but any ideas as to where I should begin poking around?

thanks!

Aaron

 

[xjwmx]

I'd check to make sure the spark plug isn't fouled and that it's the right heat range. If that didn't help, then a compression test. If your year has a wasted spark, not sure if they all do, then switch the wires at the plugs to test your ignition system.

 

[CDNTX650]

white smoke on mine was bad valve stem seal.

 

[xjwmx]

How did you check for that or did you just replace them?

 

[CDNTX650]

found out after i took the head in. I wanted them done as a "i don't want to take this motor out and apart again" precaution. My motor ran good but smoked so bad it was like a fog machine. He said they were broken and the ones that werent had no tension to them at all.

 

[AirsoftNY]

If your year has a wasted spark, not sure if they all do, then switch the wires at the plugs to test your ignition system.

XJ,

It's a 1980 Special, how can I tell if it has a wasted spark?

tx

 

[PhatTony]

As long as it's a US model a 1980 is a wasted spark setup. TCI runs one coil with two leads.

 

[xjwmx]

For TCI models, switching the wires would mainly check just the wire. If at least one cyl is running okay, your ignition system is most likely basically ok.

 

[XSLeo]

Airsoft, How long have you had the bike and how long did it set before you got it?
An engine that sat awhile, years, it can get surface rust on the cylinder walls, rings and valves. This rust can keep the rings from sealing and rusty valves get sticky. After the engine runs a few hundred miles the rust gets worn away and the rings seat in and the valves free up. This maybe your problem.
If it is riding the bike will help.

 

[AirsoftNY]

XSLeo

Thanks

Bought it at the beginning of this last summer, PO said last time he rode it was a year ago. Ran great at first and has only now started this heavy smoking.

Aaron

 

[XSLeo]

It sounds like it hasn't had time for rust, so it might be the intake valve seal on the side might have crapped out. A leaky valve seal on the intake lets vacumm pull oil down around the valve stem into the intake and into the engine.
It might be a bit of head gasket leak from the cam chain tunnel. Checking the torque on the 8 large head nuts may fix it. Swapping the four outside rubber coated washers for a brass set like Mike's sells seal as well as the rubber and hold the torque better. Adding a bit more torque helps, the stock 25 ft/lbs can be upped to 30 ft/lbs. Worth a shot.

 

[AirsoftNY]

I'd check to make sure the spark plug isn't fouled and that it's the right heat range. If that didn't help, then a compression test.

Thanks guys this is a lot to get started with. I pulled the plug (see pic) and it looks fouled with carbon, not oil.

 

[xjwmx]

It's a bp7es which is the normal heat range. I'm not the most tuned in plug reader, but I'm surprised it isn't wet if you have oil coming out of your exhaust.

I'd brush the plugs and gap them and switch the two around. Does the other plug look the same?

 

[TwoJugs]

I would start with a compression test. Both cold and warm.

 

[jurob]

Either rings or guide and seal.

Check the compression.

 

[AirsoftNY]

Hi all

Started it up today to do some troubleshooting based on this reading. This time no smoke at all though! Weird, but hooray!

Still getting very rough/erratic idle from the left cylinder, and every now and then a little backfire or pop from that carb. I tried switching the plug wires and no luck. Compression test shows about 125 on the left, about 130 on the right, this is using kickstart on a cold engine. Have not chance to check valve spacing yet...

I shot some video so you can see the difference. I tried to get a good shot of the right (good) and then the left (bad).

Any ideas?

video:

http://s20.photobucket.com/albums/b204/airsoftny/?action=view&current=P1010440.mp4

thanks again,

Aaron

 

[gggGary]

Forgive me if this stuff has been done but:

Start at the beginning. What has been done to the bike? Have you done the; I just bought a 650 now what? in the tech section?
http://www.xs650.com/forum/showthread.php?t=390
Is the gas tank rust free, have the carbs been REALLY cleaned. Are you using a fuel filter, have you set the valves, adjusted the cam chain, synched the carbs. Is it charging? Have you put a volt meter on it so you know? Have you pulled both plugs and checked for strong spark. Have you replaced the fuse box yeah I can hear you but it's smoking..... The TCI ignition is sensitive to low voltage and it will typically show up as ONE poor running cylinder when it's not happy. All of this stuff needs to be done so you have some peace of mind on the road anyways so start there.
After you have all that done, then if you still have issues it's time to start trouble shooting. Welcome aboard and help us to help you.
As for the oil outside the exhaust probably more likely from an external oil leak and not directly related to the running issue.

 

[AirsoftNY]

Gary,

Thanks for all that, I have about half your list covered (fuel stuff; new remote tank, inline filter, carbs are pretty closely synced and I've given them 2 good goings over).

I'll go after the electrical, cam chain and valves next. Thanks again!
-Aaron

 

[5twins]

Your plugs seem to indicate you're running rich. That could have caused the smoking. Too rich a mix can wash the oil off the cylinder walls, mixing it with your fuel/air mix in the combustion chamber, and causing smoke out the exhaust. I would have another look inside that left carb. Check the float setting and the float (for leaks). Check the float needle and seat, especially the o-ring around the seat. Ensure you have the rubber plug over the pilot jet.