Engine started running rough with blue smoke (1 Viewer)

[cjgoode]

Not my rig, but someone I know. Running fine no problems in the morning. In the afternoon started running rough when started back up and blowing blue smoke. Still drives but rough. I will see it later today or tomorrow. Any ideas to prepare me to help this guy. I know rings or oil rings could have failed, valve stem seal failed and fouled a plug, oil getting sucked down the carb from the valve cover ventilation.

What and how can I test. Might seafoam be a good idea. Could the oil rings have just started to stick? Chances are slim it would be that simple. Odd that is was running with no problems at all then out of the blue (no pun intended) blue smoke and runs rough.

Thanks for any help.

 

[FJforty]

Quick test, pop the valve cover, you might see a valve stem seal off its rocker. If so, push it back down to test.

Next, pull the plugs to see if one is bad. Isolation.

 

[Buckwheat]

A quicker way to find the bad cylinder(s) is to pull the plug wires - one at a time! - while it is running. The one(s) that do not cause an RPM drop are where to start looking. Pull the plug(s) and look at those next. A valve stem seal should have been causing some smoking prior to the misfire so I'm thinking maybe a ring.

 

[toddslater]

Could be as simple as a stuck float or misadjusted, dumping gas into the carb (causing the running rough) and with enough gas dumping in it, washing down the cyl walls and some nice blue smoke. A quick check the sight glass and you'll see where the fuel level is.

 

[mossman40]

Quick test, pop the valve cover, you might see a valve stem seal off its rocker. If so, push it back down to test.

Next, pull the plugs to see if one is bad. Isolation.

Quick hijack sort of......
FJforty, how did those valve seals you purchased work for you ? Did they solve your earlier problem ? I'm having similar issues.

 

[FJforty]

hijack reply.
I have the seals. Have been working long hours. Hope to post on valve stem seal replacement soon.

 

[grant5127]

I will see it later today or tomorrow. Any ideas to prepare me to help this guy.

Take along a compression tester and your favorite spark plug removal tools........