Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing GDI plug examination May 2020

We've been talking about the Ford 4cyl plugs for a while on and off. The Duratec seems to have a remote coil pack, whereas the GDI has four coil packs - one over each spark plug.

When I did this job on my Duratec, it showed some water ingress, and the plugs were progressively more corroded front to back.

When we took delivery of our new GDI at BHM, the journey home was in torrential rain, as it often has been in this Morgan. within 500 miles, I fitted an engine cover to keep water away from the plugs. This was 2016. Since then we've done 7,500 miles. I reckon that over 4,000 of those miles has been in heavy rain. One of the great delights of Morgan, is to drive roof down in rain. I do it when I can. Once coming back from Oakmere we had heavy snow over the Snake Pass, and that was great fun, but the roof was up.

Anyway, to check the plugs, first I removed my engine cover, which is two nuts. Then the coil packs are fastened using a single set screw on each. The electric plug is a three pin latched connector, and the unlatching tag is white. With these disconnected, the coil pack pulls up and out. The plugs are deeply recessed, and need a small modern plug socket with a medium length extension, and ratchet handle. It's important to hold the tool exactly vertical to undo without damaging the plug. They all came out easily, with no trace of water or corrosion.

I've always used coppaslip on plugs, but it seems that ceramic grease may be preferable. Either way, note that lubricating the threads may affect torque wrench settings. Personally I use "feel" based on many years experience, sometimes having sheared things off in the distant past. This time I used ceramic grease.

Before applying the grease, I cleaned the threads. There was brown gum about half way up the threads, and using a bit of WD40 and a fingernail/rag combo, most of this can be removed. When unscrewing, the threads were "tight" and sticky. Refitting the plugs went in all the way easily by hand. Take a bit of time to start each plug, keeping the socket absolutely vertical. Plugs with a taper seat lock onto the taper immediately they tighten up from finger tight. It's not the classic quarter turn you use with conventional compressed washer plugs, so literally a tiny nip with the socket from finger tight is all it takes.

Then, replace the coil packs, and fastener on each, and reconnect the electric plugs. It's that simple. Around a leisurely hour of "Lockdown Engineering" time.

Image 1: Engine cover removed. Four years on, and lots of wet driving...….you just wouldn't know.



image 2: Plug number four, usually the least affected by corrosion and water ingress. Plug type is CYFS12Y1



Image 3: Plug number 1. The most exposed, and often the most corroded.



Image 4: Cleaned plug with coil pack.



So the thing is, if you fabricate an engine cover to keep the water out, it also keeps the engine remarkably clean. And checking the plugs is quite a simple job.