Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing CRC GDI Valve Cleaner

Hi all,

I recently applied a can of this to my GDI Plus 4 and thought I'd let you all know how I got on in case anyone else is contemplating the same. I wasn't experiencing any of the symptoms from intake valves fowling but reckoned that since all GDI engines are prone to this issue and my car has already done 29k miles I'd do something to prevent it.

I considered taking the inlet manifold off to take a look at the back of the valves and maybe fitting a catch can to the PCV breather at the bottom of the engine but that would have been a lot more work.

The procedure was quite easy, steps below.
• Start and warm the engine
• Got the engine revs just over 1k by wedging a bit of waste pipe between the seat and accelerator.
• Removed the breather pipe that attaches to the air intake just ahead of the throttle body.
• Sat squirting the can into the opening in very short bursts until the can was empty.
• Stopped the engine and left for an hour.
• Took the car out for a run.

NB. When I 1st put some revs on, the exhaust threw out a really big cloud of thick smoke (which annoyed the neighbours), there was a little more smoke for about 500m, after that all went back to normal.

There has been no noticeable effect (good or bad) so far, all I have is little peace of mind for only £40. I intend repeating in about 5k miles and then every 10k. Only time will tell if it is worth doing.

And just to be clear I have no affiliation with CRC or this product, I'm not endorsing it and have no idea if there are any other similar products on the market.

Regards

I dont think that would have done any harm but from inspecting intake valves from various GDI BMW's it seems clear that a sort of very hard concretion forms on the back of the valves so I doubt an aerosol would make much difference. The safest thing is not to let crankcase vapours get anywhere near the intake on these types of engine. I plugged the hole in the inlet manifold and let the crankcase breath to a catchcan and atmosphere when my GDI was new (6years and 25k miles ago) and the intake valves are still like new.

That reminds me of my triumph herald when I was 17. I put valve cleaner in and ran it up the road. Huge amounts of smoke, very entertaining.
Within a week the car stopped. It turned out that all I had left of valves (before cleaning) was coke so the cleaner disolved my valves!
Those were different days....

Nick

Yep, did the same to mine 4K miles ago, nothing in the catch can yet.

A bit of a ramble..

My guess is that whatever issue exists re the engines legal requirement to ingest the by-product induced by crankcase pressure, may be to designed to "save the planet" by some measure..? To create a catch can system would seem to undermine that to some degree, and if nothing is caught then it seems either nothing is being expelled by the crankcase or that the "fumes" are just escaping and creating whatever damage to the planet that fumes might do..?

I guess as bores, piston rings and valve guides wear there may be more oil in the combustion process, and thus perhaps creating a higher degree of crankcase pressure and heavier oil expulsion may ensue via whatever "breather" system is employed..? If a catch can is fitted, it may fill to the brim or beyond , though perhaps the MOT inspector would have failed the engine on excessive emissions before things ever get to that stage...? I think catch cans were a race car development to reduce the chances of oil fouling up the surface of the race track and the mayhem that could ensue....

I hail from a time when first introduced to the workings of an engine that manufacturers had designed a system whereby a pipe could be found attached to removable cover on the side of the engine block in the location of the cam followers, the steel pipe exited the cover and pointed directly downward. In time if the fumes from an old worn engine got so bad they might enter the car, a longer flexible tube might be attached, in the hope the fumes might end up than in the cabin while on the move.... resulting on the expelled oil lubricating the road surface, and with so many vehicles likewise equipped, the oil building up in time until the next rainy day, at which time it could catch out the unwary,who might usually be a young m/cyclist, and one who had not learned of that specific danger...? I still bear the scars..(-:

Yeah for sure it is nice to think one`s engine innards are clean bright and shiny, types he who used to polish the internals of his m/cycle engines to remove all the casting marks etc.etc.etc.. So yeah I can associate with a degree of that way of thinking. I usually stripped and/or polish my m/cycle`s engine for something to do when I could not afford the petrol to go for a good run, just wanted to be involved with machinery...and involvement with the machinery has been a major pastime for me over quite a few decades, as no doubt it will be for very many like minded souls...? (-:

Today however my spanners gather cobwebs, and adding to the expense of motoring like never before, a time when I find I too own machinery that has all the EFI, DI and so much else in the way of gubbins.. I find I am not inclined to be concerned enough over the build up of crud on the back of my valves to think too much about it as once I would have, well at least until such a time as I might find an actual change in performance, and defined precisely as being down to cruddy valves....?

With a fun machine putting out something like 400HP, given my age likely driving style ( I type the word style in jest) and current average annual mileage, I doubt I might notice any engine performance drop off in my lifetime..? I do wonder at the excesses of horse power in modern machinery was just manufacturers ways of working round all the emission regulation, and the effects it had on engine performance expectations over the average customer`s expectations of the lifetime of the engine...? Of course if you are VAG you could try to cheat the system...(-:

I suspect that we can all enjoy our Internal combustion engined machinery in our own way, involving a degree of personal preferences, works well for me. Currently feeling most fortunate to have an old carb fed +8 that can at times roar like a bull, might even spit the occasional flame and has been remarkably oil tight over the 20 or so years I have owned it.... What`s more to want.. Happy days..?