ryoder Posted December 17, 2014 Report Posted December 17, 2014 I put fine wires in around 20 hours ago and had a bad runup today. I couldnt clean it off despite trying repratedly. I pulled four bottom plugs off and took them to my mechanic for inspection. This one was the culprit. It didnt fire at all in his tester until sandblasted it clean. I think its oil soaked. Also posting a pic of the wire end which has some corrosion.
ryoder Posted December 17, 2014 Author Report Posted December 17, 2014 I put fine wires in around 20 hours ago and had a bad runup today. I couldnt clean it off despite trying repratedly. I pulled four bottom plugs off and took them to my mechanic for inspection. This one was the culprit. It didnt fire at all in his tester until sandblasted it clean. I think its oil soaked. Also posting a pic of the wire end which has some corrosion.
Mooneymite Posted December 17, 2014 Report Posted December 17, 2014 How aggressively do you lean after start and during taxi? That's where most folk pick up that kind of fouling. Lead fouling is one issue, oil fouling is another. From the pictures, it looks like some of both, but I can't tell for sure.
N601RX Posted December 17, 2014 Report Posted December 17, 2014 The best way to clean finewires is to use a dental pick to remove the leadballs and not sandblast them.
slowflyin Posted December 17, 2014 Report Posted December 17, 2014 Although it could be many things the most obvious for my engine would be running to rich on the ground. I lean very aggressively during ground ops. Often I'll give it a little throttle to maneuver and it will stumble so I'll have to richen slightly. Lean as much as you can stand.
rbridges Posted December 17, 2014 Report Posted December 17, 2014 you could try swapping the plug positions and see if the same plug or wire fouls. It could help with the diagnosis. 1
larryb Posted December 17, 2014 Report Posted December 17, 2014 Regarding that corroded lead, is that the only one, or were the others corroded? I'm wondering if that lead, being corroded, caused a weak spark on that plug leading to the fouling? 2
Marauder Posted December 17, 2014 Report Posted December 17, 2014 And since we are picking on your airplane, you might want to deal with the rust on your engine mount. 3
Hank Posted December 17, 2014 Report Posted December 17, 2014 By "lean aggressively," they mean pull the red knob half to two thirds towards cut off, so that if you need more throttle to go over a bump, through grass or uphill, you have to richen the mixture some.
lamont337 Posted December 17, 2014 Report Posted December 17, 2014 And since we are picking on your airplane, you might want to deal with the rust on your engine mount. I think that's actually the mount for the lower cowl section... 1
ryoder Posted December 17, 2014 Author Report Posted December 17, 2014 I lean almost till it quits. This plug had oil and lead but more oil than any other. I cleaned the plug leads on all the bottom plugs and the runup was perfect. Id like to fix rust I just need to know where and how.
jetdriven Posted December 17, 2014 Report Posted December 17, 2014 As N601RX says, do not sandblast the fine wire plugs. Tempest and Champion both say it strips the iridium coating off and ruins the plugs. Second, that's a lot of oil. It should by dry. Is this on all plugs or just one cylinder? The MMO hydro lock trick may help free up stuck rings if that's the cause. Also, try keeping a minimum of 1000 RPM on the ground , and 1200 RPM when stopped in the ground. It may help with lead fouling. 2
ryoder Posted December 17, 2014 Author Report Posted December 17, 2014 Oil just on that cylinder. The others were dry.
N33GG Posted December 17, 2014 Report Posted December 17, 2014 How long since major overhaul or top overhaul on that engine? You might be looking at something other than typical fouling going on such as, but not limited to, a broken piston ring. I would be finding out what is going on...
M016576 Posted December 18, 2014 Report Posted December 18, 2014 Dude, you might have a cracked oil control ring or some cylinder wall damage... That's alot of oil, I'd scope that cylinder at a min. 1
ryoder Posted December 18, 2014 Author Report Posted December 18, 2014 I will recheck the plug in five hours tach time. I have a feeling its an oil ring. Ill ask about scoping.
bonal Posted December 18, 2014 Report Posted December 18, 2014 I had a cracked oil ring on a car years ago and that thing smoked like a mother are you seeing any smoke?
N601RX Posted December 18, 2014 Report Posted December 18, 2014 I had a couple of broken oil ring several years ago and was using about 1.5 quarts an hr. What is your oil burn?
ryoder Posted December 18, 2014 Author Report Posted December 18, 2014 I burn half a quart in a three hour flight typically.
Cruiser Posted December 18, 2014 Report Posted December 18, 2014 My crystal ball says there is addition cylinder work in your future, Not much of a Christmas present, how many hours on that cylinder? How hot does it normally run?
ryoder Posted December 18, 2014 Author Report Posted December 18, 2014 I dont have an engine analyzer. The cylinder is at 2500 snew.
drapo Posted December 18, 2014 Report Posted December 18, 2014 I dont have an engine analyzer. The cylinder is at 2500 snew. That's one of the time where you're happy to own a C... Just learned that I'll have to change a cylinder on my E, with labor, it's going to cost me $3000 just in time for X-Mas! 1
N601RX Posted December 18, 2014 Report Posted December 18, 2014 If I remember correctly from earlier post isn't this engine the original engine and never been overhauled other than cylinder work? If so if it were me I would keep a very close eye on it while getting enough time on it to determine the overall condition of the rest of the engine. Otherwise you may be spending money on cylinder work now and find out 6 months later that it needs a complete overhaul. For what its worth we put new cylinders on our old 67 cessna with 2200 tt on the original engine several years ago. Although we sold it a few years ago I still fly it occasionally and at 2600tt on the original engine it still runs fine.
ryoder Posted December 18, 2014 Author Report Posted December 18, 2014 So what would your cost be if you had a C?
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