Moss Motors, Ltd

 I have a 79 MGB that runs great, fine oil pressure ect. But when it warms up and im crusing, oil burps up the serarator causing thick smoke. It smokes for a few seconds till the oil passes and stops, Then does it again. Also alot of exhaust-like smoke comes out of the separator hose. Now i cant plug that line because it causes oil to run out from the dipsick, and i cant let it hang because oil sprays everywhere. What can I do to fix it? I only thing i have tried so far was cleaning out the freash air hose from the front of the car to the run on valve, no luck. I figured maybe if the evap system is clogged it could cause extra pressure in the crankcase contributing to the oil burp and heavy smoke. If anyone has any ideas or suggestions it would be greatly appreciated.

Not much help, but read here.

http://www.mossmotors.com/forum/forums/thread/18804.aspx

you might try installing some copper wool in the breather tube between the oil separator and the intake.  A copper scouring pad  is a good source for this material.  This worked for me, but its just a a patch to correct a problem. 

Does your evap canister connect to the crankcase?  Mine does and  since I disconnected it,  the problem went away, but it might be coincidence.

Try temporarily  disconnecting the line from the valve cover to the canister and se if it still does it.  Let is sit at least overnight after a run before you retest it, then make your decision about what to do.

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-Michael

  Ill give that a try. I think what i really need to do is pull the whole evap system apart and make sure its flowing. I say that because this morning my anti run on stopped working. Now when i shut the car of it chokes for a second. As of right now i have the separator hose runing into the oil fill, but it cant stay like that forever.

my current theory is that gasoline ain't what it used to be. I heard that over and over again for 20 years at my last job from old timers.

I'm sure its true since formulas do change and its a safe bet that the fuel in the late 70's doesn't look like the fuel now, but whether that is actually causing an issue is up for debate.  Maybe fumes from the tank and carb bowls are contaminating the oil and it behaves like its extra thick until the stuff cooks out.  I don't know for sure, but removing the line between the VC and the evap canister cut way down on the condensation that accumulated inside the covers and breather line for me.  I'm tempted to rig up something that sends the fumes into the carbs (only while running) and not through the crankcase.  I may look at a modern car and see how they handle it.

 

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-Michael

 I was thinking about making a catch to go in line, out of an old fuel filter. It would have to let the gasses through but catch the oil and re-route it back to the sump or head. Ill do that as a last resort because i really want to get to the root of the problem. I e-mailed John Twist but havent got a reply yet.