Valve Grind & De-coke on 6.9

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SELfor50

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There is no question posted regarding a Phantom engine. Similarly, there is no question posted about Laphoaig.
Regards,
BenzBoy


Laphroaig??! I took your advice, and put some in the tank at Sandown yesterday..worked a treat!! :D ;)
 

SELfor50

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Ok... sorry, back on topic. :)
 
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Styria

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Some interesting comments, RonB. There is a follow up to this thread which refers to the use of an engine lifting hoist when re-installing heads.

How did you manage with the head on the right hand bank ? Do you attach the exhaust manifold prior to fitting up the head ? We couldn't do it as it simply would not clear the steering box. Thus, we removed the exhaust manifold but, in the end, did away with the hoist and used man power.

Whilst we managed in the end, two mistakes we made that stand out quite clearly. One, I should have removed the Brake Booster, and secondly, we should have left the fitting of the long head bolts till the heads were in place. But, you live and you learn. Regards Styria
 
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Okay, we've had no further comments from RonB regarding the re-fitting of the right hand head. Obviously, I have read his posts on the M100 site and I hope that he will continue to contribute from time to time - in fact, all the time.

I should also point out that I have commenced another thread dealing with this work subsequent to the re-fitting of the heads and other various components. It is hoped that the two threads, side by side, will illustrate some of the issues and results ensuing therefrom.

A huge concern on my part had been the presence of water in the oil - in fact, it got so bad that despite an oil and filter change, the fresh oil was completely caramel coloured after a mere 22 kilometers. Some action was needed badly.

Once heads were removed etc. etc. , I set about getting rid of that white sludge. Surprisingly, it wasn't nearly as bad as I had envisaged. Nevertheless, the engine degreasing gun and copious quantities of Kerosene (some 15 litres in total) were pumped, sprayed, and filling up of the oil reservoir, plus spraying into all orifices and corners and cavities with engine oil drain plug in and out, also in the Timing Chain section, in other words I really gave it the treatment in every which way. It took hours of cleaning up the various messes of kero, petrol, degreaser etc. etc.

Furthermore, I was really worried what I would find oil pressure wise once I decided to install another oil pipe from the back of the engine to the gauge in the instrument cluster. Remember, Gleaming Beauty had been bought with a non-functioning gauge some thirteen years ago, and a repaired sump and the fact that someone had crimped the line did not fill me with a lot of confidence - frankly, I was worried as to what I would find. Just a hint this time - my fears have been completely dispelled - at least, so far and the engine has been hot enough for the auxiliary fan to cut in at 85 degrees after some 32 kilometers of driving - these are the "baby steps" I am referring to in another section. Regards Styria
 
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Just to bring you guys up to date. I decided to check the tune of the engine in Gleaming Beauty - at least the fuel mixture. Removal of the plugs indicates that the mixture appears to be perfect with the electrodes being a nice light grey. In fact, it would appear that the engine is running very cleanly - last time, prior to fitting the spark plugs, I cleaned them on the wire brush of the bench grinder - those 'cleaning marks' are still in evidence some eight hundred miles on.

I suspect that the correct setting of the mixture may have been facilitated by abl567's mixture analyzer. Clever little machine. Thanks Anthony. Regards Styria
 
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abl567

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Your welcome Styria, I'll bring it along on the track day!
 

SELfor50

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Your welcome Styria, I'll bring it along on the track day!


Mixture analyser??? How's it work?? By emmissions? can you hook it up to a k-jet 450?
 

John S

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Mixture analysers are very easy to use if you have a pre cat converter car, as you just place the sampler tube up the exhaust pipe and take the reading. If you use this system with a car fitted with a catalytic converter you get the wrong reading, so you must tap into the exhaust manifold before the cat converter.
 
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Hi abl567, looks as though you may have one interested party already - yes, SELfor50, Anthony's machine is suitable for K-Jet systems.

On a personal note, and another valve grind and de-coke follow up, I can also report that the car blows absolutely no smoke at all, whether it be blue or black, and oil pressure is absolutely spot on - even on the recent hot day (36 - 38 centigrade last Monday), at idle, and the engine temperature at a whisker over 100 degrees, oil pressure was above the half way mark.

In my quest to keep this engine absolutely spic and span internally, I will soon be changing engine oil and filter within the next week. With all the internal engine cleaning, and cleaning of the oil canister (both many times), the engine oil has remained remarkably clean and there are no longer any traces or evidence of oil emulsification. I am stoked with the result of the job. Regards Styria
 
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Hi BenzBoy, I have already changed oil and filter twice - using cheap oil which, surprisingly, is holding up well. Certainly, when I look at the oil pressure gauge with engine running.

I am almost inclined to use one more lot of the cheap oil, and filter, for say a thousand miles or kilometers, and I might even give the internals of the sump and oil reservoir another clean up with kerosene before re-filling with a fresh lot of Castrol Magnatec and another new oil filter. I really think it's going to be beneficial in the long run. Regards Styria
 
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Just an update on 'Gleaming Beauty' and the way she is performing. As indicated in my previous post, I have changed oil and filter again - in the week leading up to 18th January.

Apart from removing the plug from the small sump, I also drained the oil cooler that is a standard fitting on high compression engines, and in additionI also removed the drain plug from the bottom of the oil reservoir. Surprisingly, that opening had to be unblocked again on account of accumulation of 'hardish' sludge which prevented the oil from draining.

Oil has remained quite clean since the initial refilling after the valve grind and de-coke.....and now, with the latest oil and filter change, it is even cleaner.

I have also done a short fuel consumption test by driving to Glenbrook and back again to Baulkham Hills area - economy driving on the M4 returned 19.5 miles per gallon, although in suburban use, I am quite a way short of that fugure. I have noted 'pinking' of the engine even under fairly moderate application of acceleration and I am in the throes of effecting some adjustments. More on that later.

Otherwise, the engine is fine - nice and quiet, good oil pressure and a decent amount of 'get up and go'.....and it is NOT smoking from the exhaust. Regards Styria
 
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All this latest Gaff has emanated from Styria's pen - Regards Styria
 

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Hi Styria, I to have had some "ping" under hard acceleration that I've not experienced before. Conspiricy theory, CRAP FUEL. A little ATF helps reduce the ping.
 

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With your high compression European engine, it sounds as though our Australian high octane fuel is off slightly (was it 2% alcohol? At least one brand is 2% alcohol but does not publicise it!), or the ignition needs retarding a degree or two.
 

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BP 98 Octane, 8.8:1, textbook ignition setting at tdc and no pinging in my Euro 6.9.

Do you Pacific Rim guys not get decent petrol:D

If you are using 95 octane you would possibly need to retard your idle timing by up to 9 degrees on a euro. (From memory the book says 3 degrees retard for each 1 octane reduction from 98). This will be accentuated if your heads have been planed.

When I purchased my 6.9 off AMG69 the first thing I noticed was faint detonation on hard acceleration at low speed - I remarked about it on the test drive.

I checked the timing with a light and found it very advanced at idle as the engine had been set on a dyno and while it worked well when revved the low rev part was not good. Turned out the vacuum advance was not working as the pipe had come out of the elbow in the manifold.

Pleased to hear the car is running well Styria with only some minor adjustments needed.

Bill
 
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Hi WGB,, just about 100% of the time, I purchase 98 RON rating petrol, invariably from BP or occasionally Shell. To be perfectly honest, I have done very little tuning on Gleaming Beauty as I wanted to see the engine settle in first.

When I noticed the pinking (you'd only hear it occasionally, even before the de-coke), I just knocked it back by year - in other words, without the use of a timing light. The 'pinking' has gone, but I overdid it a little, but hopefully I will recheck everything over the next few days. Regards Styria
 

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Hi WGB,, just about 100% of the time, I purchase 98 RON rating petrol, invariably from BP or occasionally Shell. To be perfectly honest, I have done very little tuning on Gleaming Beauty as I wanted to see the engine settle in first.

When I noticed the pinking (you'd only hear it occasionally, even before the de-coke), I just knocked it back by year - in other words, without the use of a timing light. The 'pinking' has gone, but I overdid it a little, but hopefully I will recheck everything over the next few days. Regards Styria

I can't imagine it is easy to set by ear but all it should need is TDC at idle with the aircon off and all hoses connected and a timing light.

It seems to make an enormous difference when set precisely.

I would think the clean combustion chambers would lower the compression even with a lightly resurfaced head.

Bill
 

John S

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In the good old days (first cars before dwell meters and timing lights were common) we always set the advance by ear. Loosen the distributor, advance until the revs stopped increasing, then back off a fraction, check it then lock in position. Paper tube to the carbys to check even flow. I eventually made myself a manometer and purchased a "Colourtune" sparkplug which made smooth running much quicker & easier to set up.
 
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