Leaky exhaust valves?

My engine isn't doing to well. Idles roughly on the choke, when warmed up won't idle at all. I removed the air cleaner after turning off the engine and found a cloud of exhaust rising from the carb. There's also a lot of exhaust escaping when I remove the oil filler cap. Could anyone confirm if it's a valve issue? Engine is a 1.6 l on a 1976 GOlf LS

There is a breather on the metal rocker cover which does gunk up over time, there is a metal gauze which clogs up.

Try removing the rocker cover, block the hole or I put a long bit of rubber hose and make sure it's sticking up and with the rocker cover inside down pour "Gunk" engine degreaser all in the rocker cover and fill it up over the metal gauze and leave it to soak over night, next day wash it out by spraying water from a hose pipe down the outlet to flush it all out. Leave to dry in the sun then refit.

Might not be your problem but worth having a look?

Thanks, I'm gonna have a look at it tomorrow. The air filter housing did have some gunk in it where the breather hose connects, didn't know there was a gauze in the rocker cover.

Sure hope it's not the valves..

Could also be a plugged exhaust.

Found some pictures I posted before, you can just about see the gauze here, it's was the worst I've seen before….

https://vwgolfmk1.org.uk/forum/index.php?page=topicview&id=big-block-injection_2%2Fmk1-gti-compression

Soaked the mesh filter in carb cleaner today, but it didn't help anything:/ Not too encouraged by the mayonnaise on the cover either, but it could still be condensation as the car has sat for longer periods at a time this winter. It doesn't consume any coolant either.. Anyway I'm taking it to a shop for a compression test over the weekend.

If it was leaky exhaust valves then the fumes would leak straight into the exhaust pipe, not back into the carb or rocker cover. I would say that the smoke from the carb after you switch the engine off is more likely caused by over fueling or fuel leaking into the cylinders after you switch off the engine. That could be caused by a leaking needle valve in the float chamber. The smoke from the oil cap could be the worn piston rings causing the engine to breathe heavily so you do need to have a compression test. That build up of mayonaise in the rocker cover is probably normal if the car hasn't had a good run.

Milky oil on the dipstick, or cap is that you make short runs in your ride as to the store and back. usually 5-10 minutes or less, and your car doesn't get up to operating  temp to burn the condensate out of the oil…

If after a good run, with the car to temp, then you may have a blown head gasket, or oil cooler.

Went back at it this morning, thought I hadn't checked the oil for a while.. Turned out there was an extra litre or so with gasoline in it!!! Replaced it immediately as well as a spare needle valve and solenoid, and the thing runs like new! Hopefully not damaged by the gas though. I used a thicker washer under the needle valve just in case it wouldn't hit the float, and haven't seen any smoke from the carb yet.  So thanks all, especially Saulty your advice was a life saver

Glad to hear you got it sorted. I had at least an extra litre in my oil and it stank of petrol, caused by leaking fuel injectors. That was how I bought the car and I don't know if it was run with that much petrol in the oil but I drained it out and filled with fresh oil. Touch wood, the car has been running like new for two years now and covered 4000 miles so hopefully yours will be ok.

Well I gleefully took it for a longer drive today, and now the oil reeks of gasoline again:/ The carb has been rebuilt and I've replaced the jets and needle valve, so it is strange it's still leaking.. There's exhaust from the oil cap as well, so I'm having a compression test over the weekend