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'73 MGB; smoke from engine compartment,..

Hello, the latest is some kind of pressure build-up inside the valve cover. It seems as if this pressure is forcing oil out around the cover seal then the fan sprays it over the hot bits making smoke roll out of the engine compartment. I can take the fill cap off, place my hand over it for a few seconds and when I take it off it makes a noticeable chuffing sound. I tried tightening down double gaskets with and without goop but no luck. The smog pump was taken off years ago and some kind of ports on the valve system were plugged off. There is smoke trying to escape from the carbon filter canister near the passenger side firewall and whatever electronics controlled it's outlet have snapped off and disappeared. A disgraceful, viscous gray smoke rolls out from the tailpipe with plenty of water dripping. If this car ever had a catholic converter it's been cut out. Factory carbs replaced by weber

36something down draft and set once 25 years ago. No smog test where I live. Has anyone encountered a plugged engine syndrome before? ta-rah.
Reply to
on the buses
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Pressure build up.

All the hoses clear so the inlet manifold sucks the excess back into the motor. These do deteriorate colapse, fill with crud, etc. EGR clear??

r
Reply to
Rob

I dont think you can seal the smoke in, better to identify the source of the problem.

First thought, It could be a simple case of head gasket failure. Look for coolant loss or oil under the coolant filler cap. Worst case would be coolant water in the crankcase oil.

2nd thought. Is the engine in rough condition, could it be badly scored bores or broken ring/s pressurising the crankcase.

Oh & by the way Tks for your query gave us all a laugh The Word is 'catalytic'

P
Reply to
Pointer

Check the charcoal cannister in the corner of the engine compartment. You can replace the charcoal with fish tank filter charcoal. The cannister or one of the hoses leading to/from it may be clogged.

Dan D '65 B '76 B Central NJ USA

Reply to
Dano58

Thanks, that's what I did 8 years ago and I'm sure it's time to renew it. I disconnected the inlet to the canister just to see if the problem would go away but it did not seem to. I'll try and pull the valve cover this week and see if that rear tube fitting that feeds the cannister line is plugged.

Reply to
on the buses

Groan, well I was low on coolant. That would explain the tailpipe steam. No cream in the oil cap yet.

Impossible, I rebuilt the engine myself,.. twice.

Ah, a jest from the us radio program, "car talk". A minister calls in with an exhaust problem concerning his catholic converter,..

Reply to
on the buses

Converts water to bioethanol perhaps? :-)

Reply to
Pointer

What you are experiencing is excessive "blow by". The piston rings and cylinders have worn to a point where they can no longer hold all the combustion pressures and a portion of the exhaust gas leaks past the rings into the crank case pressurizing it and forcing oil out between the gaskets and sealing surfaces. Some options exist to sovle problem: 1. Rebuild engine or at least put new rings in it 2. Run a tube from the valve cover down past the tranmission the vent the blow by past the passenger compartment. 3. Due to water dripping out the exhaust you may have a damaged head gasket, replace it.

Reply to
Neil Clough

Reply to
on the busses

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