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

Well, the cars back together and started (after a few tries) but has the engine fault light on, also thinks it's got no petrol but I'll sort those things another day. Just some tidying up of wiring and pipes to do.

I didn't get the back of the valves to look as good as Keith's so didn't take any pictures but they are not bad now and should be ok for 20k miles.

Reason it took so long....

I got really hacked off a couple of days in, it was going very slowly and my back was complaining. I went looking for a mobile Walnut Blasting service, found a local one who said he needed to come out to give me a quote but didn't commit to a date and then I only got to leave messages for him, so gave up and went back to scrubbing.

The main difference between Keith and I was the type of cleaner used, I already had a can on the CRC stuff, which worked but I would suggest using Keith's if you try it. As for me I might take the inlet manifold off to have a look but will book it in for Blasting next time.

I did fit a catch which will need monitoring and may/may not slow down the fouling of the valves, time will tell.

Regards

A brief update. Today I eased the inlet manifold away from the head and looked at my inlet valves at 10,000 miles. I didn't take a photo, because acces is poor and it would look the same ar Marks. In fact the carbon deposits on mine are black and shiny, but not as thick. Realistically, because they are buried so far down in the head, cleaning in situ is inevitably difficult and time consuming. So for now it's back together. I decided to use a single port for the valve saver kit, because the manifold is quite a thin moulding, and so making four sealed ports is far harder than a single port just downstream of the throttle body. More on this to follow once installation is completed.

So glad I've got a Duratec.

Apparently it cam be a thing on some diesels for the same reason. As usual the internet is a feast of opinions.

Update time

Petrol engines will coke up. I think the art of decoking has been lost because it's no longer an afternoon's job to lift the head, remove eight valves, clean, grind in, refit and off you go. I watched a Duratec/GDi strip down on You Tube and I'm not even sure taking the head off is possible in the Morgan. And there are complications with the front timing cover and the cams. Obviously it would all be do-able, even at home, but would not be a quick job.

So what are the options for GDIs?

Do nothing. The simplest option, but with an inevitable outcome, and depending who you believe, might be in a little as 30,000 miles. When that day comes, the most expensive option is...........
Remove the cylinder head. Whether this is done at home or at the dealers it will be the most time consuming and expensive option.

The in between options are.... apply a chemical cleaner into the intake. There are a number of products on the market which are squirted into the intake with the engine at fast idle. The theory being that the wetting and soaking of the inlet valves will wash away carbon deposits, which obviously in this scenario exit via the combustion chambers and exhaust, and the cat. There is a test on You Tube of half a dozen GDI cleaners. Each product is discharged into a glass beaker, and the time it takes to discharge is noted. Next a carbon coated valve, each from the same engine, is heated to 400/500c, and immersed in the liquid for the same time as it takes to discharge each product. The second test is to leave the valve for 48 hours soaking in the products. The short version is that none were impressive. None made a significant difference to the deposits.

Another You Tube site suggests putting carb cleaner through the engine intake systen at regular intervals. But the truth is that we don't have a solution. (No pun intended).

The "easiest" way to clean those inlet valves is by going down through the inlet ports and physically removing the carbon. There are eight valves and because access is so tight, and because you need to ensure the valves are closed on each cylinder as you do it, this will take time, and will need just the right tools to make it worthwhile.

The bottom line of course is that our Morgans, well most anyway, don't do high mileages. I've managed 10,000 miles in seven years but it's hardly world record material. So you might just isolate the breathers and carry on enjoying your GDI.

Anyway, down to the nitty gritty.

At 10k miles it's time to get the plugs out for a routine inspection, and to clean the threads and re-apply a whiff of ceramic grease. I strongly recommend you use an engine cover, and these must be handmade unless you chop one around frm a Ford. Without a cover, the engine will get wet, and water may travel down past the coil pack seals. If this happens, you may find corroded plugs. My cover has kept everything dry, and the plugs were in good shape. I use a short length of heater hose to get the plugs out, because my plug spanner doesn't grip well enough.

Here you can see the single fastener which secures each coil pack. The electrical latches work well, and once unlatched, a slight bend downwards releases each connector.



This image shows how buried the plugs are in the head.



And this one shows my hi tech removal & replacement tool.



I decided to stick my neck out and try the JLM Valve Saver kit. After liberating the inlet manifold I decided to use a singlr port feeder nozzle. I did get the four port spider, but the manifold is thin and will be tricky to drill and tap. I didn't really want nuts inside the manifold for obvious reasons. The plastic just downstream of the throttle body is slightly thicker so I went in there. Being so close to the throttle body should get a reasonable distribution across all cylinders.
Here it is, bang in the centre of the image.



The tank must be high mounted and there's really only one place it can go. I made a hanging bracket out of some scrap aluminium profile, and added a leather buffer where it contacts the inlet hose.



The pipe run is quite neat.





And after wiring up the low fluid level warning light, I added the fluid. I intended to mix with Methanol, but a test mix in a beaker showed that it doesn't mix with this product....so it's the neat fluid. (As linked higher up in this thread).
https://lpgshop.co.uk/flash-lube-valve-saver-fluid-0-5liter/



The calibration is 15 drops per minute at tickover and that was easy enough to set up. The requirement is 1ml of valve saver to 1L of fuel, and so it's a bit trial & error until a couple of refuels should sort this out. This is uncharted territory, so we have no idea or game plan going forward. Whether this treatment will stop further build up, of even wash away the current build up, only time will tell, and arguably that will be in another 10k miles
At some stage I will get the emissions checked before the MoT and report back. The fluid is said to not affect catalytic converters, but like everything else in this test, we won't know for some time.

Thanks for the detailed post, let's hope it works as intended - time will tell. Have you also sorted the breather plumbing to stop the dirty gases recycling back into the engine?

Yes Les, about 2k miles ago......the cam cover has a filter to atmosphere, Blanked off into the inlet, and the crankcase breather is disconnected, and venting to atmosphere. No effect over 2k miles from doing that.

The drip feed has no effect on tickover either.

Good work Dave

Being involved in restoration in the early 90's I was brought up on decoking engines, the old boys I worked with used to say....

"There's only one way to decoke an engine properly, the head off way!"

However, they did advocate one other method that if completed regularly from new, would significantly extend the period before the head needed to come off for the first time.

The technique was to take a plant sprayer, the type that can be adjusted to give a really fine mist, it was then filled with tap water. Yes, you hear correctly just pain old tap water! Importantly, before you execute the 'plant sprayer decoke' the engine needs to be properly hot, not just idled in the workshop until the temp gauge says it's hot, but driven and put under load until it's properly what we used to call 'Italian Service' hot.

You then remove the air cleaner, hold the engine at 3,000rpm and spray your fine mist of tap water into the carburetor choke, the skill is not to overdose as the risk is you may hydraulic the engine. In practice it's not hard to get the dosing right, what you're listening for is a drop in engine speed, as soon as you hear the revs drop slightly stop spraying and blip the throttle to save the stall, it's definitely a two handed process.

What amazed me when I first saw the 'plant sprayer decoke' being demonstrated was just how much cr*p came out of the exhaust, the method definitely works as we had the head off the old 70,000 mile Mk2 Zephyr more or less as soon as the engine had cooled, our vacuum gauge already showed a burnt valve, the purpose of the 'plant sprayer decoke' was just to show me (the apprentice) how it worked and how effective the method could be.

I was told ideally it should be done every 3,000 miles and from new, this was back in the 1950's and 60's when the old mechanics I worked with learnt their craft. The practice of decoking engines largely disappeared from the mid 70's on as fuel and engine oil quality had improved massively, piston rings, bore honing techniques, piston and valve guide materials/machining were all way way better too so the combustion chambers started see a lot less oil making decoking a thing of the past.

Then along came the practice of force feeding the engine with its own blow-by gasses, this wasn't great but we largely got away with it especially after the advent of multipoint port injection, however, ironically by the early 2000s the need to decoke an engine returned with direct injection.

So perhaps it's time for the return of the 'plant sprayer decoke'

BTW, if anyone is still doubting how effective the method is, they clearly haven't seen an engine with a head gasket failure where the seal between the cylinder and a coolant passageway has been breached, when you lift the head off an engine with this particular type of head gasket failure the cylinder seeing the coolant will be completely steam cleaned, while the others are all as dirty as each other.



This is why the valve saver kit should work, but it's possible for the purposes of keeping the cylinders carbon free it may actually work better if it's just filled with good old tap water

There used to be simple kits in the late 70's that just had a sort of soft bag washer bottle, thin pipe and a fitting to drill and tap into the intake manifold, that you just filled with tap water

It just sort of injected itself via the negative intake suction, but was sold under the more economy / better performance headline

Yep my tight BIL had one on his clapped out Corsair