PTK Posted November 10, 2015 Report Posted November 10, 2015 8 minutes ago, mcpilot said: OK guys.. I am open minded.. I have a first run engine.. 1995 was the year it was made. How would you all go about an OH? New cylinders? keep the A3B6D? I'd seriously consider a Lycoming factory OH'd A3B6. Under 30k$. Genuine Lycoming and with roller tappets. Quote
jetdriven Posted November 11, 2015 Report Posted November 11, 2015 5 hours ago, teejayevans said: For me and probably many on this board, the 20 year limitation is a non starter. The limitation on cores is 35 years old. It's only 20 years for the discount. Quote
frcabot Posted November 11, 2015 Author Report Posted November 11, 2015 Well, mechanic told me there is a significant amount of aluminum in the oil filter (probably from the piston) and he feels the engine needs to come off and be overhauled. So there it is.So, back to my original question. What are some good overhaul shops for a Lycoming IO-360-A3B6D?The pricing of Corona Engines looks pretty competitive even with California sales tax (I was quoted about $18,500 or so).http://www.coronaengines.com/Engine-Overhaul Has anyone ever used them? Quote
frcabot Posted November 11, 2015 Author Report Posted November 11, 2015 On 11/9/2015, 11:28:31, Tony Armour said: frcabot, Since I have been watching the results/hanger talk of the recent Cirrus landi...errr...crash.....errrr....save... I'm curious, did you make an immediate turn toward the airport and mostly on my mind, did you start descending before you had the airport made or ? No judgements here but what you did and the thought process behind it....I am very interested in. Did controllers give you instructions ? If you are familiar with the Cirrus incident you will understand my questions. I hope I have learned from it. Regarding what to do on your engine (based on auto experience, may mean nothing) Once you get shrapnel in one cylinder it can make it's way back thru the intake to other cylinders. I'm sure all will be checked out well before putting you back in the air. Anything I could do to make it safe to fly back to my home mechanic....I might do that. The cheapest reman cylinder I could find or a good used one to buy or borrow. Get it home and then make a decision. Once again GREAT JOB ! Made an immediate turn to the airport and descended very gradually. I was actually very high on the approach and had to do some S turns to lose altitude to not overshoot the runway. Better than being too low, though. 2 Quote
jetdriven Posted November 11, 2015 Report Posted November 11, 2015 1 hour ago, frcabot said: Well, mechanic told me there is a significant amount of aluminum in the oil filter (probably from the piston) and he feels the engine needs to come off and be overhauled. So there it is.So, back to my original question. What are some good overhaul shops for a Lycoming IO-360-A3B6D?The pricing of Corona Engines looks pretty competitive even with California sales tax (I was quoted about $18,500 or so).http://www.coronaengines.com/Engine-Overhaul Has anyone ever used them? how much aluminum are we talking about 1 Quote
jetdriven Posted November 11, 2015 Report Posted November 11, 2015 8 hours ago, Shadrach said: Did you seriously just say that most overhaul shops will not reuse a cam? Neither overhauls nor factory rebuilds have traditionally gotten new cams. I am not sure if the roller tappets require a different cam, so perhaps all conversions are getting new cams at this time. You do realalize that there is a thriving cottage industry based on testing and regrinding/resurfacing serviceable cams and cranks for overhaulers (I think 1 in 20 residents of Oklahoma works in such a shop). What exactly is Lycoming making in the house these days? We had our engine field OHd back in 2000, we considered a factory overhaul at the time. I remember being surprised at that time that Lycoming were only making connecting rods and cases. Everything else was subcontracted. I also know that prior to roller tappets every Lycoming factory overhaul or factory rebuilt engine came with the cam and crank that came from their stock of serviceable cores. I don't know if someone has deliberately misinformed you, or if you've just made some assumptions. But many of your notions about aircraft engines and aircraft engine overhauls are simply not true. I'm curious to know why you think a roller tappet removes the possibility of the classic Lycoming cam failure. What data do you have the support this? How does a roller tappet prevent corroded cam from spalling? Riddle me this. The cam & crank in my 67F are original. They currently have 2990hrs and were reused when we OHd with new cylinders in 2000 at 1880hrs. Prior to overhaul the engine was positively abused by my father at times… No preheats, often long periods of inactivity (as much is 18 months without turning). The engine was run under a regimen of all of the old wives tails of the 60s: pull it back to 25" for climb. 25" x 2500 50ROP cruise. No oil filter for the first half of its life. And yet despite being run hard and hot at times, running with unfiltered oil and having been subjected to long periods of inactivity, the cam and crank were in great shape and ready to be retuned to service after a quick trip to Oklahoma. Why would I give up donuts for an unknown? I know several new Lycoming engines that have $hit the bed within 10 years of service. I have a family member who lost an IO320 that was less than 10 years old and had less than 1000 hours on it. It was flown to >250 hours in the preceding 24 months. There are members of this forum who've had cams self-destruct on relatively new engines for seemingly no reason. Certainly not age or lack of use. To the OP, choose carefully when deciding how to go about replacing an engine. There is a lot to understand about the process. If the cam looks good, I would leave that 400hr bottom end alone. Then it's narrowed down to deciding to replace just the offending cyl or replacing them all. That's a decision best made after thoroughly examining the failed cylinder. Im not defending the Lycoming factory, I have my issues. But I think the only thing that solves or at least seriously mitigates the possibility of cam/lifter failure is the roller cam, and there's only one source. I know about a dozen people personally who have experiened cam failure, but none with rollers. None with google search with roller lifters, save for a guy who goes by the handle of docthrock, he had a Rocket and the engine sat in a basement for 18 months and after 200 hours it had worm trails on the cam, it was still running and not spalled, BTW. He crahsed it and opened it up and found this. Rollers roll over defects, flat tappets pull and spall metal. I do agree with Shadrach that the older cams, say, before 1990-1995 do seem to be made of better metal and they dont have as much of this problem, but not as good as roller cams. But nothing fixes it, and I havent read about a roller failure but I have a friend, AaronK25, who is on his 3rd engine in 5 years. Several more on their second. Quote
Shadrach Posted November 11, 2015 Report Posted November 11, 2015 3 hours ago, mcpilot said: OK guys.. I am open minded.. I have a first run engine.. 1995 was the year it was made. How would you all go about an OH? New cylinders? keep the A3B6D? How much should I budget? I am not currently in need of an OH just curious... My opinion is… It depends. When I needed engine work in 2010, it was important to me that the shop be local. In the event that there were any issues, I wanted to be able to have a face-to-face. Some people are more concerned about branding. Having a factory engine may help you if you decide to sell your airplane in the near future. There are reputable shops around the country that can provide both an impressive pedigree and a reliable engine without having to go the factory route. My take on roller tappets is that they are more marketing campaign then usable technology on a certified Aviation engine. They are used in high performance engines to run aggressive cam profiles without having to increase duration (ramp up). Roller tappets also significantly reduce frictional losses. On the downside they add weight to the valve train. So how would roller tappets be beneficial in a certified aviation engine? In my opinion they're really not. It is my understanding that Lycoming had to alter the cam profile to keep power output within certification levels. They engineered the new cam to negate the true benefit. Will roller tappets help prevent cam spalling? I think the jury is still out on that, but I have serious doubts (as I alluded to earlier with my steamroller comment). Cams in the IO360 don't typically fail because of lobe/lifter pressure, they typically fail because of pitting/corrosion. I don't understand how a roller tappet will prevent this but I'm all ears if someone has an explanation. We had our engine done back in 2000, it was built by a friend of the family who ran a small FBO and managed an airport in the mid-west. I feel he did an excellent job and would recommend him, but he's out of the business and working for the FAA now. 1 Quote
mcpilot Posted November 11, 2015 Report Posted November 11, 2015 take a look at the roller cam... roller.tiff Quote
jetdriven Posted November 11, 2015 Report Posted November 11, 2015 OK, so now we're at TWO in thousands. We have perhaps 100 on this board right here with flat tappet cams. Give me that background on that cam, was that engine running? high wear metals? Spalled roller lifter? Or was it a prop strike that, in absence of that, would have made TBO. There is NFW that anyone can claim that a roller cam and lifter set is inferior to a flat tappet cam derived from a 1936 buick. Quote
mcpilot Posted November 11, 2015 Report Posted November 11, 2015 I think the roller cam will spall due to disuse corrosion just like any other... Quote
jetdriven Posted November 11, 2015 Report Posted November 11, 2015 7 minutes ago, Shadrach said: I think the jury is still out on that, but I have serious doubts (as I alluded to earlier with my steamroller comment). Cams in the IO360 don't typically fail because of lobe/lifter pressure, they typically fail because of pitting/corrosion. I don't understand how a roller tappet will prevent this but I'm all ears if someone has an explanation. If the jury is still out, they are stupid. Hundreds and really, thousands of flat tappet cam failures in the same mode, and we have two corroded roller cams in 10 years, neither of which were failing, they were found on prop strikes. Spalling happens when metal is picked up from sliding friction, rollers dont fail like this. They may fail, but show me 40 roller cam failures on this board and I'll believe it. 2 Quote
jetdriven Posted November 11, 2015 Report Posted November 11, 2015 4 minutes ago, mcpilot said: I think the roller cam will spall due to disuse corrosion just like any other... LETS SEE ONE SPALLING FAILURE OF A ROLLER CAM LYCOMING. Quote
frcabot Posted November 11, 2015 Author Report Posted November 11, 2015 17 minutes ago, jetdriven said: how much aluminum are we talking about Don't really know since I'm not there to see it. He said a "significant amount." I think some would be expected from the piston damage but one would expect it to hopefully be flushed out through the oil system. Quote
Shadrach Posted November 11, 2015 Report Posted November 11, 2015 13 minutes ago, jetdriven said: OK, so now we're at TWO in thousands. We have perhaps 100 on this board right here with flat tappet cams. Give me that background on that cam, was that engine running? high wear metals? Spalled roller lifter? Or was it a prop strike that, in absence of that, would have made TBO. There is NFW that anyone can claim that a roller cam and lifter set is inferior to a flat tappet cam derived from a 1936 buick. I'm not claiming it's inferior, I'm claiming that the real benefits aren't realized in a certified engine that's limited to 200 hp. Quote
jetdriven Posted November 11, 2015 Report Posted November 11, 2015 1 minute ago, Shadrach said: I'm not claiming it's inferior, I'm claiming that the real benefits aren't realized in a certified engine that's limited to 200 hp. 1 minute ago, Shadrach said: I'm not claiming it's inferior, I'm claiming that the real benefits aren't realized in a certified engine that's limited to 200 hp. IDK but if my 35K engine fails one more time I am out of the certified airplane market. Its already done it once, it lasted 1100 hours. Some people i know have had it happen twice. No roller engines I know of have failed in this manner. ZERO since 2005. Isnt that at least correlated to a more reliable cam and lifter set and reduced failure? Now it is more expensive. Cetainly. But a premature overhaul at 250 hours is pretty expensive too. Quote
Shadrach Posted November 11, 2015 Report Posted November 11, 2015 22 minutes ago, jetdriven said: IDK but if my 35K engine fails one more time I am out of the certified airplane market. Its already done it once, it lasted 1100 hours. Some people i know have had it happen twice. No roller engines I know of have failed in this manner. ZERO since 2005. Isnt that at least correlated to a more reliable cam and lifter set and reduced failure? Now it is more expensive. Cetainly. But a premature overhaul at 250 hours is pretty expensive too. Byron, I am sure you know more about this than I do. I don't have my finger on the pulse of what's been going on at Lycoming. However, given the experiences that you've had, I understand why you would be more informed. I don't take your anecdotal analysis of the situation lightly. I trust that you're correct regarding the lack of roller tap at failures. However, we must remember that correlation does not equal causation. Any number of factors that could be responsible for the lower failure rate. Perhaps Lycoming is using a different manufacturer for the new camshaft...or maybe it's the less aggressive cam profile…or maybe it's that only half of the lifter/lobe is likely to fail. I don't know. The only thing I would say is that it's my opinion that if one's engine makes it to TBO over a long period of time (more than 15 years or say 37 years in my case) and the internals are serviceable at that time, then those components are likely the most well proven and lowest risk components one could use in their rebuild. I feel it would indeed be foolish to purchase a different engine if one already had an engine in one's possession that had proven it's "metal". 1 Quote
jetdriven Posted November 11, 2015 Report Posted November 11, 2015 Just now, Shadrach said: Byron, I am sure you know more about this than I do. I don't have my finger on the pulse of what's been going on at Lycoming. However, given the experiences that you've had, I understand why you would be more informed. I don't take your anecdotal analysis of the situation lightly. I trust that you're correct regarding the lack of roller tap at failures. However, we must remember that correlation does not equal causation. Any number of factors that could be responsible for the lower failure rate. Perhaps Lycoming is using a different manufacturer for the new camshaft...or maybe it's the less aggressive cam profile…or maybe it's that only half of the lifter/lobe is likely to fail. I don't know. The only thing I would say is that it's my opinion that if one's engine makes it to TBO over a long period of time (more than 15 years or say 37 years in my case) and the internals are serviceable at that time, then those components are likely the most well proven and lowest risk components one could use in their rebuild. I feel it would indeed be foolish to purchase a different engine if one already had an engine in one's possession that had proven it's "metal". I mostly agree with that. But most engines are torn down now from cam and lifter failure, not from 2000 hours on the clock. And roller cams seem to be the solution, not "load it with a new cam and lifters" and it runs 400 hours on average before the next spalling event. The most recent I know if is the hangar mate next door with a Piper Arrow in a flying club. it flew several times a week. Quote
frcabot Posted November 11, 2015 Author Report Posted November 11, 2015 Received more info. While I thought I remembered that the plane had a bottom overhaul ~400 hours ago, that doesn't seem to be the case. Instead, it was a bottom "repair" after the previous owner suffered a prop strike. So the broken items were repaired, but not everything in a bottom overhaul was done. For example, it doesn't look like the camshaft was overhauled/replaced as in a typical overhaul. Moreover, although I don't have the logs to verify, the mechanic tells me that the top "overhaul" from ~1000 hours ago also wasn't a full overhaul. It doesn't look like the valves, for example, were replaced. Given this information, I'm feeling more confident that a major overhaul to new limits is the way to go given the high time on engine. If I do a top overhaul now and a bottom overhaul a year from now, I still have an engine with 2000+ hours SMOH, which is going to affect the resale value pretty significantly (not that I'm expecting to sell it anytime soon, but still...). What are some recommendations for OH shops? Has anyone used Corona Engines? Quote
frcabot Posted November 11, 2015 Author Report Posted November 11, 2015 17 hours ago, MB65E said: Nice airmanship!! Give Ken at Lycon in Visalia a call or Chris At Pacific Continental in LA a call. Both are awesome shops!! The good news is you are half way between 2 of th best shops on the west coast!!! With 2100 TSO on the engine I would count my blessings and overhaul the engine. Bummer it it had to happen with pax onboard. Ping me when you finish your trip to Santa Monica. I'll buy lunch!! Love to here the entire story. -Matt Thanks Matt, I'll give them a ring! It sounds like it may be 1-2 months before I can finish the trip, though. :-( Quote
frcabot Posted November 11, 2015 Author Report Posted November 11, 2015 On 11/9/2015, 6:53:44, chrisk said: Great job on the landing! So very glad you are here to tell us about it. Thanks to you and all the others who have posted. The nice thing to know is that our pilot training does work if we stay calm and fly the plane. 3 Quote
jetdriven Posted November 11, 2015 Report Posted November 11, 2015 9 minutes ago, frcabot said: Received more info. While I thought I remembered that the plane had a bottom overhaul ~400 hours ago, that doesn't seem to be the case. Instead, it was a bottom "repair" after the previous owner suffered a prop strike. So the broken items were repaired, but not everything in a bottom overhaul was done. For example, it doesn't look like the camshaft was overhauled/replaced as in a typical overhaul. Moreover, although I don't have the logs to verify, the mechanic tells me that the top "overhaul" from ~1000 hours ago also wasn't a full overhaul. It doesn't look like the valves, for example, were replaced. Given this information, I'm feeling more confident that a major overhaul to new limits is the way to go given the high time on engine. If I do a top overhaul now and a bottom overhaul a year from now, I still have an engine with 2000+ hours SMOH, which is going to affect the resale value pretty significantly (not that I'm expecting to sell it anytime soon, but still...). What are some recommendations for OH shops? Has anyone used Corona Engines? copy the logs and post here. We were all operating on your statement that the bottom end had 400 SOH and the top 1000 SOH. 1 Quote
frcabot Posted November 11, 2015 Author Report Posted November 11, 2015 11 hours ago, mcpilot said: The numbers I was quoted: IO360 A3B6 Lycoming overhaul (not reman) was $28,500 with new cam, roller tappets, new case. Any parts that do not meet limits are replaced with a NEW part. OH Shop $29,800 to start. That also includes a new cam. They cannot offer roller tappets and will not use a new case. If your case is bad.. you pay extra. These shops also used to reuse cylinders... How many of those do you think made it to TBO? Why not have the latest technology with the roller tappets and remove one of the biggest causes of engine failure? As far as reusing a cam? That is one of the highest stressed items in our engines. I want my engine to have the best chance of going to TBO again, I would replace. Most of the large OH shops will not reuse a cam or tappets. If you have your small shop do the OH or do an owner assisted one what warranty do you get? The quote I am getting from Corona Engines, for a major overhaul to new limits (not a field OH) is less than $20K (about $18.5K, to which I have to add some CA sales tax). That includes a 2 year or 500 hour warranty, whichever comes first. That's a pretty significant difference between the price of a Lycoming factory overhaul. With Corona, it sounds like it's several thousand dollars more to convert to an A3B6D with the two single mags, so I'm not inclined to do that if I go with them. The single mags may be an improvement over the dual mag, but I don't know that it's a $4K or $5K improvement. Quote
frcabot Posted November 11, 2015 Author Report Posted November 11, 2015 16 minutes ago, jetdriven said: copy the logs and post here. We were all operating on your statement that the bottom end had 400 SOH and the top 1000 SOH. Just have the bottom entry log for now. It's cryptic and I've asked the shop (One Stop Aviation in CA) to send me the work order. Basically, it sounds like the bottom was torn open and repaired as necessary, but not overhauled to new limits. Parts that didn't need to be replaced or overhauled, such as the camshaft for example, weren't. "Disassemble engine & inspect for prop strike. Magnaflux crankshaft & all steel parts. Zyglo case. Check for hidden damage. Counter weights worn. Replace rod nuts & bolts. Replace main & rod bearings. Replace seals, gaskets & c.w parts. Magneto inspection. See listed parts. All current AD's complied with. Reassemble engine, ready for installation." I'll ask the mechanic for the top entry. Quote
jetdriven Posted November 11, 2015 Report Posted November 11, 2015 23 minutes ago, frcabot said: The quote I am getting from Corona Engines, for a major overhaul to new limits (not a field OH) is less than $20K (about $18.5K, to which I have to add some CA sales tax). That includes a 2 year or 500 hour warranty, whichever comes first. That's a pretty significant difference between the price of a Lycoming factory overhaul. With Corona, it sounds like it's several thousand dollars more to convert to an A3B6D with the two single mags, so I'm not inclined to do that if I go with them. The single mags may be an improvement over the dual mag, but I don't know that it's a $4K or $5K improvement. Does that include new cylinders? New cam and lifters? overhauled dual mag? Quote
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