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

As a Duratec Plus 4 owner I'm keen not to appear to be gloating, but do honestly think a Plus 4 with Duratec engine is the four cylinder Trad Morgan sweet spot.

However, apparently the GDI does make 10hp more from new, but for how long?

This sort of thing has to be absolutely dreadful for efficient air flow over the back of the valves!



When I bought my Duratec Plus 4 a well respected Morgan specialist commented that it was a shame it wasn't a GDI as he could give me 180hp with the 'Club Sport' package.

I said......

"I'm not keen of direct injection as the valves get gummed up; and anyway, a GDI would have been up to £10k more to buy than my 2012 Duratec Plus 4".

The Morgan specialist responded by saying valve gumming isnt an issue on the GDI, well, clearly it is, I think what he meant to say was.......

"Morgans are typically occasional use hobby cars, so I haven't seen one with enough mileage to have presented the problem... YET!"

At the end of the day a post 2011 Duratec is the exact same car as the later GDI, but to my mind a GDI is trickier to tune, has a drive by wire (DBW) throttle that I don't overly care for over a cable, and comes with this valve gumming issue too. Anyway, unconvinced by the expensive 180hp 'Club Sport' offering, I simply set about giving my Duratec Plus 4 quite a bit more than 180hp, and for less than the cost of a GDI 'Club Sport' kit. And any Duratec Plus 4 owner could copy my tuning recipie, largely becuase I myself simply copied it from the Fiesta ST150 crowd, and Caterham of course

As my early career was spent in vintage and classic car restoration a lot of what I worked on used a slash cut draught tube to puke oily crankcase gasses directly onto the road, now, I'm not suggesting we should go back to those days, but 'Blow By' is nasty old stuff so be careful what you do with it. When we started to see manufacturers making their engines ingest these disgusting, caustic oily vapors the old mechanics I worked with would say....

"Making an engine eat its own poo is never going to end well"

And they were right of course, but we kind of got away with it as there was always some petrol present to wash the poo away, port fuel injection being especially good at this compared with a carb. But as soon as direct injection came along I couldn't help being reminded of that 'poo' comment from those old mechanics I worked with all those years ago.

I'm genuinely interested to see how effective a catch can will be on a GDI and I can see how it'll help, however, to me the fundamental problem still exists so I really can't see it being more than 50% effective. At the end of the day for a catch can to be even half effective, you still need to hold it under negative pressure, and the depression below atmosphere ultimately has to originate from the inlet manifold.

Given all this, I don't care how good the separation method is, invariably some gasses are still going in that engine

However, in support of all the GDI Plus 4 owners out there, I sincerely hope I'm wrong!

Mine has done a couple of thousand miles with the breathers venting to air, and so far no light. Even when I put Seafoam through the inlet tract and created a battleship worthy smokescreen, it was OK. Which was surprising. The cam cover breather feeds in just ahead of the throttle body, so blanking that off and venting to air shouldn't make any difference, and in fact after regular inspections, this breather stayed spotless inside. The crank case breather will pulse oil fumes into the inlet manifold, and that seems to be the source of the oil deposits. Because the air/fuel mixture is already set when it enters the inlet manifold, blocking the breather hole in the manifold and venting to air shouldn't make any difference to running either.

Monty, Gloat away, that's fine.

DaveW, Whilst some of the oil on the backs of the valves will come from the breather some will also come down the valve guides, IMHO.
Cheers
John

Does anyone have a diagrammatic showing the breathing circuit before (as supplied) and after modifications? I would like to modify my system to reduce the likelihood of the inlet valves 'gumming up', but don't particularly want to fit a catch can. I think I would find it easier to understand what needs disconnecting, blanking off, fitting with a breather/filter, etc. if I could see a diagram.

Just to finish off my account and add a few more details...

I've managed to clear the EML fault code - I tried a cheapy dongle from Amazon (EM327 with Torque OBDll app) but could not get it to stay bluetoothed to my phone. I got it to work on my wife's VW Up! - so I don't think it was user error. It wouldn't communicate properly with my Golf GTD either, so I gave up on that and will send it back to Amazon.

Then I went and bought a "Streetwize Car Diagnostic OBD II" tool from Toolstation and that worked within a few seconds at finding and cancelling the fault codes (which showed up as a throttle sensor issue amongst a couple of others - I should have been more diligent at making a note of them but got carried away wanting to see if I could cancel the light!)


My conclusion about what had happened to cause the EML is that I was daft enough to switch on the ignition while all the connections were unplugged when I was working on the valves and the manifold was off - and the ECU had a fit about lots of things being missing (throttle body, knock sensors, coil packs). But as soon as it was all back in place and the light was cancelled it was happy again - I've just driven back home 15 miles with no problem.

It may be some kind of wishful thinking/placebo type effect but the car seemed livelier than before, so cleaning up the valves may be helping it breathe more easily and maybe producing a bit more power. It would be interesting to take it back to the rolling road I used a while ago to see if it is any different, but I'm not sure I can be bothered as it's a couple of hours drive away from here.

Re the request for a diagrammatic of the breather system - I have no idea, but the top hose from the cams to just before the throttle body is very clear to see and understand. The other "guilty" one from the crankcase to the inlet manifold is very short and deeply buried behind/underneath the inlet manifold. Here's a screen grab from Robert's video:

As Dave has already recounted, the only end you can reach with the manifold in place is the connection to the manifold and that is out of sight and tricky to disconnect, but not impossible. It's a squeeze the textured side tabs of the clip and pull straight off - there's no give in the hard plastic hose to twist it off.

I'm hopeful that there will be no further build-up of oil/burnt-on oil/carbon on the valves now that I've diverted the crank breather to an oil separator and then to atmosphere. As others have found there seems to be little to no oil coming from the top breather, but in order to monitor things I took the opportunity of the manifold being off to create an "inspection port" in one of the inlet tracts close to the head, where I can poke the endoscope to get a look at one pair of valves in the future, without having to take the manifold off. It's a stainless M10 machine screw cut down to just a few mm long so similar to a sump plug, screwed into a tapped hole in the quite thick plastic of the manifold, with an O ring to ensure a good seal. (probably sacrilege to some, but it's my car and I'll do what I like with it!)

Far from sacrilege, given a couple of full screw thread rotations in the plastic, that’s a good idea. Would add some high temperature silicone as thread lock and sealant.

I'm please to hear you've solved the fault light. Your code reader looks the same as mine, just a different name.
That "inspection port" is a good idea.

One question, did you need any new gaskets for the job or are the seals "O" rings and so could use them again?

Thanks for the suggestion, but it's a fairly snug fit in the threads I tapped so I'm confident it won't come undone. The O ring acts as a sort of "spring washer" as well. But I'll check it in a few miles anyway.

The diagnostic reader looks similar and certainly seems to function in the right way - I saw a very positive review on the Tube, so I thought it was worth a punt - and it was available over the counter, locally. I was guilty of impatience, wanting to get it sorted in good time for a long trip away (including a little track session at Bicester) at the back end of next week.

The seals are very much reusable. Fancy green O rings in recesses (see from 15 minutes into the video) - careful cleaning of the mating surface and the seals before refitting, not that they were very grubby anyway. I refitted very much guided by a YouTube video


Particularly regarding the torque settings mentioned (20 NM for the manifold bolts and 10 for the throttle body - those settings certainly felt about right for those type of fittings). There's a bit more space around the engine bay in the Morgan than in the Escort featured in the vid - also connections and the lower manifold bolt are accessible from the top only for us, whereas the guy in the vid accesses some from below.

The 500ml can of Holts EGR cleaner was plenty for doing the valves. I also used some for cleaning the throttle body and the manifold, spraying into all the holes and swooshing it around several times - to get rid of any residual oil lurking on the internal surfaces. There's still a small amount of cleaner left in the can. It was considerably cheaper than some of the seemingly similar products such as Seafoam or CRC. It smells a bit like cellulose thinners and I was careful to avoid getting it on my hands.

For the S1 Roadster ford do not recommend cleaning the throttle body with such a spray as it can strip off the plastic coating on the body. It will be Iso propyl alcohol probably which is one of the thinners for nitro cellulose based inks & paints.