I run at 25 squared by default, but at higher altitudes, WOT, which is often less than 25 MP, and maybe 2,300-2,400 rpm. I consider 6 quarts to be "full"
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Maybe I need a top overhaul?
- Thread starter tom paul
- Start date
Just out of curiosity, what oil brand, type and additives has the engine been running on?
I use aeroshell w100 plus and cam guard.
Update: I haven't been able to fly much since the oil control ring flush procedure, but I did about 1.5 hours the other day. I am thrilled to report that the oil is NOT BLACK and it hasn't been significantly consumed after that much flying, which is not what would have been the case prior to the oil control ring flush. I had been contemplating a top overhaul, based on my oil usage and blackened oil, but now I feel much better about it! Thanks Mike Busch!!!
Coincidently, I have just over two hours after the flush. My results are great. It worked for me as well.
Resurrecting this thread. My plane is down for a while as I upgrade the panel. Waiting on the July 9th Garmin zoom to inform that process... in the meantime, I am thinking a lot about the cylinders. They are Titan Nickle from 2009. #1 shows good crosshatching, but the rest of them show little to none. The oil control ring flush seemed to help for a while, but as of last time I flew, which was september 2005, I was back to using close to a quart per hour, with the oil turning black right away after an oil change. I was planning to fly a bit once I have my new panel with lots of new engine monitoring, and asses the situation. Now I am reconsidering that since the evidence of extreme blow by is undeniable. That coupled with a 1200 hour ECI nickle cylinder engine makes me think a full top overhaul is the way to go.
Various searching is giving me ambiguous results, so I am asking here: Can I do it myself? I did not build this airplane. I have experience rebuilding porsche 356 engines (horizontally opposed, air cooled four cylinder) from the crank up, so I am comfortable following the instructions and doing this. Like I said, between perplexity, google, claude etc, i am getting conflicting answers. What is the law around this? Maybe I do most of it and then have an AP with me for the final assembly and get a sign off?
Thanks, brain trust.
Various searching is giving me ambiguous results, so I am asking here: Can I do it myself? I did not build this airplane. I have experience rebuilding porsche 356 engines (horizontally opposed, air cooled four cylinder) from the crank up, so I am comfortable following the instructions and doing this. Like I said, between perplexity, google, claude etc, i am getting conflicting answers. What is the law around this? Maybe I do most of it and then have an AP with me for the final assembly and get a sign off?
Thanks, brain trust.
OK, so legally you can do this yourself, you don’t need an A&P or any certification - since you have an Experimental aircraft. Changing cylinders is not hard at all - but there are little tips and tricks (learning to read the Lycoming Overhaul Manual is a trick in itself sometimes….), things that folks who have done this before can help with. If your Porsche 356 blows a jug or throws a roid, you coast to the side of the road. The stakes are a little higher with an airplane engine! Not saying you can’t or shouldn’t do it, but you might look for somone with experince to help you do it - and you will learn along the way.
You might be experiencing the same problem many of us had with the ECI Cerminil cylinders - rings that were sheddign a laminated layer. Caused oil consumption to skyrocket. Replacing the jugs with standard Lycomings fixed the problem for me - some others used Superiors.
If you competent with the horizontally opposed, air cooled Porsche 356 engine, you’ll be fine with doing a top overhaul on a horizontally opposed aircraft engine. I’m an A&P. I recently did the TOH of my Continental C90-16F. It ain’t rocket science. I was advised to do one cylinder at a time and never rotate the crankshaft when all the bolts are not fully torqued. This may not apply to your engine.
I purchased 2 digital torque wrenches to precisely torque things perfectly. I removed the connecting rods, inspected the journals, and replaced the connecting rod bearings. A year ago I had come to the rather rude conclusion that my engine had the incorrect dipstick and I had routinely been flying around on one quart of oil for the last 3 years.
Read the manual, I didn’t and ended up doing things 2x to bleed the lifters down. Again may not apply to your engine.
So only one quart of oil drained out during oil changes???
Since you’re having to ask, I’d say get an a&p to work with you on your first time replacing cylinders. It’s not hard but needs to be done right.
Also please please please do not use Claude/ChatGPT/ whatever AI chatbot for help on any engine work. It will only feed you nonsense. Refer to the manuals.
Also please please please do not use Claude/ChatGPT/ whatever AI chatbot for help on any engine work. It will only feed you nonsense. Refer to the manuals.
Sounds good. I am well aware of the BS that comes out of AI's "mouths". I will study the manual and get some help. I appreciate all the thoughts. I think I may do a poll, inviting experienced people to drop their best tip, because at the moment, I certainly don't know what I don't know. There is only one shop on my field and they have done a bit of careless work on my plane before, and it was very expensive. So the motivation is partly financial, but also I don't have 100% confidence in them. They did my CI last year and returned the plane to me with the hose clamp for the neoprene tube connecting the James cowl inlet port to the intake just sitting on the bottom of the cowl, not around the tube at all. It was the forward clamp, so in my view, flying air pressure could pull it off of the cowl flange, and then it could get sucked into the intake. Hopefully I would have the presence of mind to pull the alt air knob, BUT in an unfortunate coincidence, they had also rotated something around the linkage of my alt air bellcrank, to the point where it hit the cowling and wore a hole hole through it with the engine vibration, so who knows if it would have even been free to move as designed if and when i needed it. I literally screamed at them. So, part of my motivation is "if you want something done right..." I trust myself if I am slow and careful.
There is one other piece of this: The plane sat unpickled for an unintended period of 6 months. It was in a hangar and through the winter in NJ. so not TOO hot and humid, but still. I finally pickled it in April, before it got too hot and humid. So when the jugs are off, I want to inspect the cam lobes to check for any pitting, which would likely trigger a full overhaul, which I would not do myself. Thanks guys.
I agree that you should be nervous about that shop - but I bet there’s a good chance that if you check with your EAA chapter, someone might have good Lycoming experience and would be willing to help … that’s what our EAB community is for!
Yup! I have been down for a year.So only one quart of oil drained out during oil changes???
I had previously done oil changes where I only got 1 quart of oil out. I didn’t understand what I was experiencing and asked lots of questions on the Ercoupe owners forum and other sources, I never got a good answer.
Last year in preparation to fly from Atlanta to OSH I did an oil change. (I have 2 aircraft at 2 different airports) I preflighted my Aircoupe with 4 quarts on the stick at airport #1, flew it to airport #2 dumped out 1 quart of oil. I did all the normal A&P oil change things and serviced it with 4 quarts and flew it the 45 minutes home.
The next day I was going to do the same trip. When I preflighted the aircraft, it became rudely apparent that my actual oil level was 100% irrelevant to the markings on the stick. I immediately took the insurance off the aircraft, drove to Oshkosh and bought 4 new cylinders. Removed the cylinders one at a time. Removed the connecting rods. Inspected the journals (they looked great). Replaced the connecting rod bearings.
When I filled up the crankcase on completion, I recalibrated the dipstick with a drill press and removed the existing markings with a die grinder. In the meantime I did the annual and need to do my Biennial Flight Review before I can fly again.
Wow, I just saw a thread about all the issues people have been having with superior cylinders. Incorrectly machined rings, wash boarding, swapping the jugs after 25 hours! Much of the thread is praising the company for standing by the product, paying for labor and replacement parts, but Mr. io390 points out that a more robust internal QC process would be a better play for everyone. I think I'll be looking for Lycoming cylinders for my IOX 360 A4 H1N. (What do all those extra digits mean anyway? I assume configs, accessory locations, comp ratio? There seem to be so many variations!)
The major pitting typically occurs on the tappet face, not the lobe. Once the face is sufficiently pitted, it starts wearing away the cam lobe. In the early stages, the cam lobe typically looks fine, but may see pitting on tappet face. Even in later stages, the lobe appears normal, it is just shrinking in height. This oftens starts with very small corossion, then snowballs after a while, so a visual inspection is no gaurantee. Also, you can't see most of the tappet face in situ. I did an iran last year on an engine in the early stages. The two worn lobes appeared pristine, until you ran your finger over them and could feel the sharp edge. Once measured, they had lost .03" of material. The pitting on the tappets faces could be clearly seen, even when installed. We caught that when the jugs were off, though we already knew it was there, as the OH shop found embedded metal in the pistons, that was not visble to the naked eye.
I’d definitely go with Lycoming cylinders, and follow Mahlon’s ground run guide for initial break in.
I did this and it worked beautifully (unlike the Superiors which ruined themselves within a couple hours). In fact I’ve just flown my RV6 from the UK to northern Canada, started with 6 quarts and as you can see it has hardly used anything.
I did this and it worked beautifully (unlike the Superiors which ruined themselves within a couple hours). In fact I’ve just flown my RV6 from the UK to northern Canada, started with 6 quarts and as you can see it has hardly used anything.
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The lobe is surface hardened, so in the early stages it doesn't wear very much. It is only after the wear gets through the .01" hardened layer that it starts to wear agressively.
Got it thanks for that clarity. Is it possible to inspect and replace the tappets while doing the cylinders without pulling the engine and splitting the case?
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That oil looks amazing. I'm really tired of seeing carbon black oil after one hour passed an oil change. Thanks for the break-in Bible that looks like a good read and I'll follow that.
Yeah, my oil was turning black within an hour or two before the overhaul as well. In my case I did a full overhaul because the engine came from a dodgy builder originally (I found stuff like reused con rod bolts, reused oil pump etc) but in your case a top makes sense. Go with the Lyc cylinders and it should be fit and forget.
Tappets cannot be replaced without splitting the case. If you rotate the engine so that the tip of the lobe is touching the tappet face, you will get a broader view of the face. However, a clean visual inspection is no guarantee, as this often starts with non visible micro corrosion and takes time to develop into full on spalling. Once you can see it, an overhaul is required. Also, once started don’t believe it can be stopped.
Got it. Thanks. The only thing that would make me suspect corrosion is the fact that my engine sat unpickled for 7 months (oct-April) in a hangar in NJ. It has been pickled ever since. I'll probably do the top and fly. Will there be any way to assess the possible damage once I am flying again?
Generally takes 30-50 hours after an event that put corrosion on the tappet faces to start making serious metal. In the later stages you will find metal in the filter. In the later stages. You will find decent sized metal particles that have the appearance of small fingernail clippings and are a classic sign of lifter spalling.
Unfortunately, at this stage metal has been circulating in the oul system and likely will find scratches on the crank journals and possibly other parts of the.
thanks. None of this sounds good! I will do filter cuts and oil analysis often and save my pennies for a full OH.
While sitting idle for many months can create this problem, it is far from a gaurantee that it WILL happen. Cross your fingers.
