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

The indirect injection Cyclone V6 in the 3.7 Roadster has another crankcase breather variant. The main breather is on the right hand cam cover to base of inlet manifold immediately above, so only a short pipe needed with integral non-return valve. The left hand bank breathes the opposite way with a feed into its cam cover. This is achieved by a longer pipe from inlet tract fitting, located after air cleaner but before throttle body, feeding to cam cover. The relative pressure for the most part is going to be higher here than at manifold hence general breathing flow from left to right bank, and no need for non-return valve on this side.

FWIW when I checked this pipe there was no trace of oil or residue at either end, as to be expected.

I wonder if a simple water/methanol injection into the inlet tract would give enough protection to the valves to stop the build up?

Kits are available but expensive and aimed at forced induction. We need a competent expert to evaluate possible benefits, and come up with a simple kit for the GDi.

I won't hold my breath. Mine is just at 10,000 miles and I'm tempted now to take the manifold off over winter to see what 10,000 miles looks like.

The cost effective alternative would be an LPG valve saver kit Dave, these systems are inexpensive and highly effective.

https://lpgshop.co.uk/flash-lube-electronic-valve-saver-kit/

The above version uses an ECU that takes a MaP reference from the inlet manifold to meter the valve saver lube, however, in my experience the following far simpler and cheaper vacuum based JML kit that only costs £35.00, works just as well.

https://lpgshop.co.uk/jlm-valve-saver-kit/

I would add the four cyliner distribution manifold to your basket too, it's only £20 and essential to ensure an equal quantity of fluid reaches the back of all four valves evenly.

https://lpgshop.co.uk/lubricant-distributor-splitter-4cyl/

While these simple systems are designed to cool and lubricate your valve seats when running LPG which is a dry fuel, the lube used in these systems also has excellent detergent properties, this will remove any existing carbon and blowby deposits on the back of your valves while keeping it bay in future.

https://lpgshop.co.uk/flash-lube-valve-saver-fluid-0-5liter/

A 500ml bottle of flashlube only costs £15.00 and will last at least ten fills, so roughly 4,000 miles in a GDI Plus 4 which works out at next to nothing per mile, you can also mix the lube 50/50 with methanol, this gives even better blowby cleaning properties and the added benefit of cooling the incoming charge with a small increase in octane too.

https://www.ebay.co.uk/itm/354307108272?hash=item527e596db0:g:l14AAOSwCdNkIupo&amdata=enc%3AAQAIAAAA4OnfuorIBGw5Sh7iuFQG4nO0GomWMSLVsLLPMOZD444JSKLqeo5s5WWoH2WBl5%2FZWOGEQUTJcuJYYZcLH3utSGVYhHQd8Qdu996HvGp%2BTFWxXRO9zlfcxof1XSedNj4%2BhB%2B%2BWcjyRD9pOAc3FldSeMX2Cbpi3FqPnHGO6j7UeGRasK9FnDKmEiZ6GbhFZPHDyd5MASJ%2BimnZRn5MfzYIWiX4jQouqglv%2B3%2FnKuRYiknAGZvKJvfpGf2oY6vQpFXcGe9NLCUL3c2iYWmZwGRrpZKNt8AoyU%2BUTk2GlOFuR08M%7Ctkp%3ABk9SR-KX3vHoYg

You can buy 500ml of methanol from eBay for just £8.00, so for less than £25 you've bought yourself 8,000 miles of valve cleaning solution, including the kit itself & distribution manifold you’ve solved the problem for years to come and for just £80.00

Thanks for this Montegue......I need to look into this because it might just be the right solution.........!

Update: I'm going to give this a shot. What's the mix between the flash valve saver and the methanol Montegue? 50/50??

Much like modern synthetic two stroke oils, these LPG valve saver lubricants are designed specifically to be combustible without generating their own carbon deposits in an internal combustion engine. Introducing a light oil seems counterintuitive, but it's full of detergents so it works well, think Red-X "Upper Cylinder Lubricant" if you remember that stuff? Mix it 50/50 with methanol and it works even better at dissolving and removing oily deposits

BTW, don't confuse the old skool Red-X "Upper Cylinder Lubricant" with the new generation of Red-X branded fuel treatments, they are very different products that work in completely different ways. The original Red-X "Upper Cylinder Lubricant" hasn't been available for years because despite being very effective at removing carbon deposits, it's not very environmentally friendly. Because these LPG valve saver fluids are essentially the same stuff as the old skool Red-X "Upper Cylinder Lubricant" it's not something you'd want to be introducing into the engine on MoT day as you'll probably fail the emissions test, I also couldn't vouch for the long term effects LPG valve saver fluid will have on your catalytic converter, but I'd make that same caveat about a water/meth injection kit.

At the end of the day this valve gumming issue only exists with direct injection, on port injected engines we never experience the problem because there's always fuel washing (and cooling) the back of the valve. Once the direct injection valve gumming issue was identified many manufacturers solved the problem simply by adding a second set of injectors in the inlet manifold, the engine effectively became both direct and port injected.

An LPG valve saver kit is solving the problem in the exact same way, it's just a crude port injection system that's simply relying on the depression in the inlet manifold to draw the fluid into the engine. Keep in mind these LPG valve saver kits are well proven over millions of miles on LPG converted engines that would otherwise burn their valve seats out in no time at all, and you don't need something super sophisticated to do the job.

Unlike in the LPG valve saver application, I actually don't think you’d need to inject the valve saver fluid all the time for it to clean the back of the valves, so one fill could (potentially) last a lot longer than I’ve quoted above.

Accurate metering is of course essential

Has anyone fitted one of these kits to a GDi engine?

I'm going to do it over winter Les....get the manifold off and see what's going on first and then start figuring it out.

Please keep us posted with your progress. I suppose the system will only be as good as the fluid that it injects (in keeping the valves clean), and that will only be known in the longer term. I would prefer this route of prevention rather than cure.

I did contact the manufacturer and they would only tell me it was for LPG systems, and subsequently steered me to this - https://www.jlmshop.co.uk/direct-in-injection-valve-cleaner-500-ml-free-deli.html

+1 for the manifold off over winter.

Dependent on what’s found and general experience of this operation, the choice appears to be :

LPG valve saver or similar
Remove manifold at intervals and clean valves
Exchange the car for one with a different engine

Recent removal of the crankcase breather/air intake connection may help long term. Time will tell.

Have to say, my GDI with 20k under its belt currently displays a virtually straight line power curve and obeys my every command without cough, quibble or splutter.

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.