Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Workshop Note - GDI Oil Breather

Am I correct in thinking that muck on valves is less of an issue on the Duratec engine?
Bob.

No the issue is as there is no fuel in the air going through the valves the petrol being directly injected into the cylinder like a diesel. This means crankcase gases with oil flow over the valves but unlike in a standard petrol engine they aren't was off by the fuel in the fuel air mixture. Hence the concern.

To answer the question more directly...yes, it is less of an issue on a Duratech. For the reasons John stated above, though a slight typo...he meant to say the backs of the valves aren’t “washed” by the petrol/air mixture as it flows past into the cylinder.

Correct I meant the back of the valves on a GDI. Sorry for the confusion.

Understood, Thanks for the info.
Bob.

Well, after only ~200km, there was a good shot of oil/water/exhaustgases in the catch can, clearly it does catch a lot of stuff.
But the YouTuber "Humble Mechanic" had those sent in to a specialist who analysed the liquid, and it was to a very high degree just water.
So, I am considering venting to atmosphere through a breather as well now...

Just adding to this thread: experience with CRC GDI Valve cleaner by Mark.

Somewhat of a thread revival, but it seems like a good place to share my recent experiences...

Having a 2017 GDI engined Plus 4 with nearly 25k miles on the clock, I decided to explore what the inlet valves looked like, suspecting from what I've seen online that they might be getting gunged up with oily sludge and carbon from oil being burnt on.

I invested about £20 in a basic borescope that plugs in my phone and explored the combustion chambers via the spark plug holes.



There was evidence of what I considered to be normal light combustion deposits, but with the aid of the right angle mirror attachment I could see some build-up on the back of the inlet valves, albeit with rather dubious quality images:



So I decided to properly explore by removing the inlet manifold, very much informed by Robert's excellent video guide. Some of the connections are tricky to get to and undo, especially those underneath the manifold - the endoscope came in very handy for seeing into otherwise "blind" areas. Getting the socket on to the last bolt underneath would have been even more difficult without it (and I'm not looking forward to putting it back!)

But now it is off and the results are similar to what Robert found - but worse, as my engine has lots more miles. This is cylinder 2, but they are all much the same:




However there is better news as I am well on the way to cleaning them up, quite satisfactorily I think:



After looking at a number of YouTube videos about how to best clean inlet valves and ports, I assembled a can of Holts EGR and Carb Cleaner together with various tools such as an engine cleaning brush set and a set of pick tools:





The EGR cleaner seems to do a good job of dissolving the oily/carbon build-up and with some laborious scraping and brushing, then mopping out with paper towels, finishing off with a good blast with a long-nozzle airgun achieves a reasonable result (not quite as good as walnut blasting but much cheaper!). The usual caveat of only working on ports with the valves closed, apply! A ratchet socket on the crank at the front turns the engine over (clockwise only) easily enough with the spark plugs removed and coils refitted to avoid debris falling into the cylinders.

I plan to fit an oil separator to avoid the issue recurring. I'll try and update with that later.

You did well dissolving the oily/carbon build-up

The first "sports"car I owned, in 1971, was a 1959 Fairthorpe Electron Minor. Somebody else had built the kit (reasonably well) and had maintained the mechanicals (reasonably badly). On a number of occasions it took me and my girlfriend at the time, from W.London to Cornwall. But it was real heap; I kept the exhaust valves (from a Standard Ten) as a souvenir.

P.S. She married me anyhow, and now puts up with me and the Morgan.

Keith,
You've done a very good job there. At 21K miles I should do the same job on my GDI. I've got my oil catch pot half made, must get it finished.
Cheers
John.