Peter wrote:
The plug condition depends strongly on how the engine was run immediately before shutdown. It is not a good indicator of anything unless you rig the situation by starting with cleaned plugs, running at high power and lean just before shutdown and then oily plugs could indicate excessive oil being burnt. My exhaust is totally spotless so your oily plug theory isn’t right. I could get you photos of my plugs in any condition you like.
I can see that operating and shut down technique can create flooded, lead fouled, burnt carbon contaminated plugs etc, but how can you create oily plugs?
I somehow recall that you were not that happy with the goings on around your big repair in the US, so why repeat the same?
The engine shop was fine. I even flew there and visited them. It was the shipper (CEVA) who lost the engine at LHR for four weeks, then lost it again in the USA for a few more weeks. If I was doing this again I would send it DHL, which does door to door in about 2 days. They are far better organised than an air freight shipper which subcontracts parts of it to other outfits, employs the lowest grade staff imaginable and uses local white-van outfits for the collection and delivery (we have to deal with them every day at work; a few are good but most are happy to leave a pallet outside in the rain, 30 seconds after the doorbell is not answered, so they don’t get behind their schedule, or often leaving again having stuck a “nobody was in” ticket in the door with a fake time written on it). DHL would be a few k but you save that on a US overhaul over a European overhaul. Last time (2008) after the air freight “experience” I used Fedex for the return shipping and they were great; I had a unique chance to use the Fedex account of a US colleague who worked for a huge firm which had a massive discount deal with Fedex an I got it for about GBP 1k. Air freight was about GBP 500 each way. To be fair air freight usually works (we use it all the time too) but this is not an area where I like somebody to f- up because my plane will just sit in the hangar while the sun is shining and I am making one frantic phone call after another 
I can see that operating and shut down technique can create flooded, lead fouled, burnt carbon contaminated plugs etc, but how can you create oily plugs?
I think you can do it with a low power run. Anytime I look into a cylinder bore, I see a thin layer of oil there, and that is apparently correct. You need some oil to lube the piston rings.
When I did a high power run prior to shutdown, I didn’t have oily plugs. Well, only a trace.
A few thoughts. Your oil consumption is getting better. I would fly the plane. You do not have oily plugs with the exception of the last one in the picture which was minimal. The bottom plug would be oilier than the the top but both plugs would show signs.Your stacks are not oily. Never found out if the belly is oily. If yes I would see about crankcase pressurization or moved/misplaced breather line. Ck your oil filler casket and prop seal. Also JPI data. When the oil consumption suddenly started did you notice if there was a change in which cyl went lean and in what order?
As mentioned earlier, I would still ck the crankcase pressure with a plumbed AS indicator.
The problem with Cont is their crap workmanship. If a cyl makes it to 1000 hrs there is every reason to expect it to make 3 OH runs. That is assuming you pay attention to heat and Internal Cylinder Pressures. So that takes care of metallurgy. Every 750 hours pull and inspect lifters. Cont is not consistent with the quality of the lifters. Inspecting them before they destroy the cam is only prudent.
That leaves the Valve and valve guides. The weakest part of the engine. When the lifters are checked the guides can be checked for condition as well. A certain amount of play is required but too much is not good. There are values that are given I guess by the manufacturer. The valve face can be checked for normal heat patterns with a borescope. Make sure it can see the whole valve face and not just a portion of it. It is very easy to burn a valve and not know it if a piece of debris obstructs the valve from closing (seating) properly. That happened to me so I did the cyl flush and it corrected that.
I plan on using Rieger’s shop to take off my #5 and replace the stuck oil ring (all the rings on that cyl.) and rehone because Borescope showed the cyl glazed; probably due to the high oil burn. At the same time I plan on seeing what the valve looks like. If needed the valve guide and valve will be replaced and the valve seat reground manually. I understand there is an old timer there that knows how to do these things.
Oil burn on last flight was half of previous!
So I will fly now to get another data point. 85% of max HP
Also i found a loose joint on the breather pipe.
Oil on belly definitely.
Engine is a Lyco BTW.
Peter wrote:
Last time (2008) after the air freight “experience” I used Fedex for the return shipping and they were great;
My experience with Fedex is not good. Horrid customer service. Also, I’ve heard stories about them just like the “local white-van outfits” you mentioned… My guess is that they’re in Sweden only because their US customers expect them to deliver stuff all over the world and that they couldn’t care less about the local market.
Might be better in the UK, of course.
Well, yes, we don’t use Fedex at work either. They caused us loads of problems, practical and accounting. Same with UPS. We use TNT for intra-UK and DHL for all import/export. But the main reason we use TNT is because the driver is really nice and helpful, and their collection deadline is 5pm. DHL is simply the best organised company outside the USA – and usually the most expensive.
Back on topic, I have just got feedback from another pilot who has come across this and his view was that this is a bunged-up engine due to too much low power and low CHT (high altitude non-turbo) operation. His view was to thrash it at a high power and it should clear up. That figures because not only is my oil burn improving (and if the present trend continues I will be back to normal after 1 or 2 more 1hr flights) but also the dirtiest cylinders were 2,6 which are both on the LHS whose CHTs are lower than RHS (due to the oil cooler being on the RHS, as mentioned earlier).
I will have good data next week. But I won’t be doing any high altitude stuff for a bit. Today I did 1hr at 25" / 16GPH (according to this about 190HP i.e. 75% of max HP and well ROP for decent cylinder pressures) and about 160kt IAS which is a daft way to fly and one would not get very far that way.
If you need reliable commercial tracking, my fairly extensive experience with shipping transatlantic says to ship Fedex to the U.S. and DHL to Europe. Vice versa can be problematic. Best to ship using the company with the best infrastructure on the delivery end. The pickup end is virtually irrelevant because you likely put it in their hands.
I shipped a package to Norway this morning and DHL was 5% more than Fedex, I used them anyway just as I’d invariably use Fedex shipping to the U.S.
Peter wrote:
know of a firm in the southern UK which can pull cylinders, replace piston rings, etc, and which has the right tools and procedures?
I once landed there late on a Friday with a badly cracked GO-300 cylinder, oil pissing everywhere, and they had me on my way by noon on Saturday.
If that mist lifts in Sussex you could do worse than give Ian Chaplin (the owner) a call and then fly up to talk face to face.
Peter.
I once landed there late on a Friday with a badly cracked GO-300 cylinder, oil pissing everywhere, and they had me on my way by noon on Saturday.
That’s curious, not a huge number of those geared engines flying. Cessna Skylark? Neat.
@Jacko many thanks for that really great and very useful tip. That’s an easy flight for me.
However [un]fortunately my engine seems to be improving all by itself, after a good kicking up the a—e. I will know next week – unless it rains all week, which is what the MSLPs indeed suggest…
