Motorcycle Alabama

Open House => Tech Talk => Topic started by: Beck on October 06, 2015, 04:40:47 PM

Title: Hard starting ---- white smoke
Post by: Beck on October 06, 2015, 04:40:47 PM
So after my last fiasco, or riding adventure on the little husky, I now have a major issue and need some help.

The bike starts ok, and will run for a few minutes on idle, if I get on the throttle it will run until I reduce throttle and then the bike will stall.  After this the bike will not start.

Work done recently.

Rebuilt water pump
Drain oil - dark, not milky.
Replace oil, filter, oil cover o-ring
Pull clutch plates and springs.  Springs under spec and replaced.
New clutch cover gasket
Drained coolant and replaced.
Charged battery
New spark plug
Cleaned air filter

Today - borrowed a timing light to test spark.  Good light while idle and while throttle is open.  The bike stalled as expected and this time released a bunch of thick white smoke from the intake.  This bit is new and has me concerned.

I have not tried to start the bike since the smoke, in fear of more damage to internal motor.

Help is appreciated.

4stroke 310r husqvarna redhead pile of fun.
Title: Re: Hard starting ---- white smoke
Post by: springer on October 06, 2015, 05:04:10 PM
 Is the coolant level low? White smoke is water/liquid, black/grey smoke is oil. You did submerge the bike in water, right? (I forget) If so, it could be just coming from water trapped in the exhaust when the exhaust got hot.

I would say run it for awhile to get up to operating temp. If it is water in the exhaust it should stop after a few minutes,  but keep a check on coolant level to be safe.   
Title: Re: Hard starting ---- white smoke
Post by: Beck on October 06, 2015, 06:19:06 PM
Yes.  Bike took a water nap, and was showing signs of overheating.  Coolant level is steady, just can't keep it running to get the temps up.

When I opened the coolant cap, I got the beer can pressure sound, so that is pressure build up in the radiators?

Title: Re: Hard starting ---- white smoke
Post by: griff on October 06, 2015, 06:36:24 PM
Have you checked to see if you got water in the fuel?
Title: Re: Hard starting ---- white smoke
Post by: springer on October 06, 2015, 08:39:07 PM
Quote from: Beck on October 06, 2015, 06:19:06 PM
Yes.  Bike took a water nap, and was showing signs of overheating.  Coolant level is steady, just can't keep it running to get the temps up.

When I opened the coolant cap, I got the beer can pressure sound, so that is pressure build up in the radiators?
Yep, it should build up some as temps go up.

Quote from: griff on October 06, 2015, 06:36:24 PM
Have you checked to see if you got water in the fuel?

Another excellent idea. Water in the fuel will produce white smoke.
Title: Re: Hard starting ---- white smoke
Post by: bblass on October 07, 2015, 10:28:41 AM
Have you checked your compression and valve clearances? A valve hanging slightly open will cause whitish/blue smoke with fresh oil. And it will get worse as the bike runs.

If it doesn't smoke at first when you crank it, and then the smoke starts building up after 10-15 seconds of idle I'd bet you have a warped/out of spec valve(s).
Title: Re: Hard starting ---- white smoke
Post by: Beck on October 07, 2015, 10:20:15 PM
Damped the old gas and replaced with some fresh.  Bike idles ok and runs to half throttle without stalling.   Going to test more tomorrow.

Valves were checked and set less than 300 miles ago, have not checked since.  Hoping to check all the cheap possibilities first...
Title: Re: Hard starting ---- white smoke
Post by: Reserector on October 23, 2015, 12:30:11 PM
Sounds like water or debris is piling up against a fuel filter, or screen as it runs.  Once it clogs, the engine quits.  After a while, it settles and allows fuel to flow again.
Check any inline filters, and the tank itself.
If it is carburated, don't forget to check the float valve screen under the valve seat, also.
Title: Re: Hard starting ---- white smoke
Post by: 2smoke on October 23, 2015, 07:27:36 PM
Besides the fuel pump filter. There is an additional filter in the shifter side petcock, (33)

Title: Re: Hard starting ---- white smoke
Post by: KevinB on October 23, 2015, 07:53:16 PM
If it was sunk, would soppy wet muffler packing contribute to choking it out?
Title: Re: Hard starting ---- white smoke
Post by: Reserector on October 26, 2015, 07:18:59 AM
Quote from: KevinB on October 23, 2015, 07:53:16 PM
If it was sunk, would soppy wet muffler packing contribute to choking it out?
I seriously doubt it.