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:): :lol: made me chuckle,did the last two postings.

Bodger, those examples by Smaky were from the workshops Black Museum. Yes we had those in the various franchises I worked at in years past, as a sort of example to customers to take advantage of regular servicing facilites. :):

The piston ring grooves build up of carbon problem is greatly reduced by using top quality fuel, and very regular oil and filter changes. It will still however build up a limited amount over high mileages.

I guess you employed the old deliberately snapped piston ring method? Ground to a suitable angle at one end to remove that extremly hard carbon deposit? Am I correct? Slow painstaking process, especially if you have a dozen pistons to de-carbonise? Keep up the good work Bodger matie, I'm glad to see you are back posting.:thumbs:
 

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Thanks Smaky,
I haven't tried flush at all, but a local mechanic suggested it had made a difference on a few cars with sticking tappets etc..
I guess a decent oil has detergents that will do the same if it is possible.
ZF- I don't think I had a spare broken ring to use. That sounds like a good technique.
If there was some way of cleaning the slots without pulling the engine apart....
 

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Not to my (limited?:(: ) knowledge. The last engine overhauling I did, was on the FIATs we owned at that time.

I carefully removed all of the piston rings, and then cleaned the groooves with the method described? I think I mentioned it before that I then measured the piston rings with a micrometer, and they were all within the tolerances specified in the workshop manual, so I accordingly did not replace them.

Once the motor was back together and running again, it used no oil, and in my humble estimation it ran perfectly.:):
 

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You may wonder where I obtained the old rings from to use as a scrapers/ tools? As I was well in with Peterborough Motors at that time,Lancia/FIAT, I think I obtained them from their workshops scrap bin? Not really sure, I may of had them in my garage from previous jobs.:confused:
 

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Piston ring removal? A decent bench vice with soft jaws fitted. Clamp the connecting rod firmly in the jaws of the vice, with the skirt of the piston resting firmly on the soft jaws. Down to 'strongish' fingers and thumbs, with required callouses :): to gently expand the rings and remove them from the grooves slowly. You can insert strip feeler blades in the ring gaps, and then slide them around the piston at various intervals to act as expanders, and then slide the rings up the feeler blades gradually up and off. Probably the easiest method if you do not wish to break the piston rings?:):
 

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Not to my (limited?:(: ) knowledge. The last engine overhauling I did, was on the FIATs we owned at that time.

I carefully removed all of the piston rings, and then cleaned the groooves with the method described? I think I mentioned it before that I then measured the piston rings with a micrometer, and they were all within the tolerances specified in the workshop manual, so I accordingly did not replace them.

Once the motor was back together and running again, it used no oil, and in my humble estimation it ran perfectly.:):
That's interesting that it cured your oil consumption. How bad was it before?
 

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In all honesty Bodger, the FIATS which had over one hundred K on each, and were zoomed back and forth to work each and every day, used about a quarter of a litre or thereabouts, between 3,000 mls. servicing? I checked and topped up regularly, so I'm not absolutely sure.:(:
 

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That makes me wonder about some AR's appetite for oil? The Lannie's the HPE and the Thema 16V Turbo, both were very light oil burners too. Our 147 didn't require any topping up between services either?:confused: Or is there a pattern emerging here perhaps?:rolleyes:
 

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I'm a very regular oil changer and none of mine have burned oil either.
 

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When my engine was rebuilt at 82K the rings on all the pistons shows signs of fatigue ie minute cracks. Bore #1 also had a very very fine scratch .. not deep enough to catch your finger nail, etc but visible none-the-less. When the engine was rebuilt it had new rings and the bores were all glaze-busted which go rid of the scratch.

Before this the engine used the usual 1 litre in 1000-1500 miles, after it uses next to none between oil changes.

I've had the car from new so I know in that time how the engine was treated and that it had regular oil changes. It did have a cambelt failure at 73K and at 82K the #1 big end went, hence the rebuild. The big-end also occurred about the time the engine started to overheat due to a block rad. Whether the overheating caused the ring damage, I'm not sure ... but I think the overheating and the previous cambelt damage were definitely to blame for the bigend shell spinning in the conrod.
 

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What kind of oil change intervals were you on before the 82k rebuild?
 

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I just had new rings installed after going through more than 1 liter per 1000 km. The engine used Selenia Racing 10W/60 and the oil change interval was 10,000 km. The rings were way out of spec and the piston tops had a bit of carbon on them, this on an engine with less than 50,000 km on the clock. Fortunately the bores were OK. Shoddy work at the factory I suppose?

I'm going to do 1000km of town traffic, highway cruising and mad sprints to see if the new rings have cured the oil consumption problem. I saw the workshop guys removing the head so that the pistons could come out and go back in from the top.
 

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What kind of oil change intervals were you on before the 82k rebuild?
As per the service book ... it was leased for the first three years. But regular top-ups meant the oil changed frequently in between :rolleyes:

Now it's every 6K miles .... nice clean Selenia 20K 10W40 semi-synth.
 

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I think I'll be doing the 6k change intervals as well. I wonder if it can get cleaner over time?
 
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