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

On the face of it, this is absolutely the best thing you can do because logic dictates if you're not putting those nasty oily acidic blowby/crankcase gasses into the inlet manifold in the first place, you're not going to suffer the problem.

However, keep in mind the way your GDI engine manages its crankcase pressure will have been very carefully modeled by the engine designer, re-routing the muck somewhere else is all well and good, but you must also ensure in the process you're not altering the pressure balance condition within your crankcase or you'll run the very real risk of introducing other issues. If you're altering any element of the factory crankcase breathing system, even in a small way, you absolutely must ensure your crankcase remains at the correct and balanced negative pressure the engine designer intended.

Ignore this at your peril, fail to respect what the engine designer intended and you'll almost certainly just end up shifting the problem somewhere else. For example I've seen poorly thought out catch can installations cause oil control ring gumming, if your oil control rings start to gum up they will no longer be able to do their job, accelerated bore wear being the inevitable consequence.



It'll definitely work, keep in mind that cleaning the back of the inlet valve is just one benefit of port injection, the other benefit it offers is the fuel cools the back of the valve, keeping an inlet valve cool is always a good thing for longevity. Even if you've solved the gumming issue by removing the blowby/crankcase gasses at source, there are still the valve cooling benefits to be had from adding the LPG valve saver kit. Essentially, it's a crude way of giving your direct injected engine the hybrid port/direct injection solution engine designers themselves came up with as a fix once they realised direct injection was causing valve gumming issues.

I'd use a 50/50 mix of methanol & valve saver fluid, you could also add a splash of ATF as no other light oil has better detergent qualities but I wouldn't use too much as ATF is not intended to be burnt in a combustion chamber like the valve saver fluid is. The elephant in the room for the valve saver kit idea is how it may or may not affect the life of your expensive catalytic converter?

In the same way as altering your carefully designed crankcase breather system could easily introduce other issues, the designers of your lambda sensor and catalytic converter never intended them to see the combusted/vaporised byproducts of valve saver fluid and other substances. My guess is they'll probably cope OK but it is a guess, you can certainly kill a cat in short order just by running the engine on leaded fuel or even using an engine oil containing zinc. The lead in the fuel or ash deposits from the zinc in the engine oil will soon coat a cat matrix covering the rare metals that function as the catalyst, so my caveat remains regarding how the valve saver kit could potentially shorten the life of your catalytic converter and or your lambda sensor!



This is a PITA, I think you'll soon get fed up doing this at 10,000 miles intervals, I'd be looking to do it once with the intention of never doing it again because you've solved the issue at source by sending those nasty blowby/crankcase gasses somewhere else, or fixed it with the valve saver kit. However, while manually cleaning your inlet valves is a pain, it's also probably the least risky way to manage the problem. I would again recommend ATF as a very effective cleaning agent, it'll soon remove carbon and oil deposits.



That's a bit radical, you could however fit a different engine to your GDI Plus 4 like a port injected 2.5 Duratec. Your biggest challenge with this idea is the fact your engine management system is designed for direct injection, if you go with a port injected Duratec dropping the engine in will be the simple bit, what's not so simple is you'll need a suitable ECU and a new engine loom too.



Personally I think you're on the right track, start by giving the valves a good clean so you're beginning at a known base point, redirect the gasses but do try to respect the engine designer's intended crankcase pressure. Then add the valve saver kit, just be sure to monitor your emissions carefully. You will only know if you try it, but keep in mind replacing failed lambda sensors and poisoned catalytic converters could get very expensive indeed.

Good luck with it.