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Engine parts list & ideas help please.....

bret

bret

Well Known Member
So, I have lots of experience building auto, truck, marine, bike ect engines, but that's where it ends. I would like to build my power plant for my 7A, I don't know if I will save any money, or not, probably not, but still...I would like to build a 390 or 400, so here is the first question, do I need to have the case modified for this, or can I just bolt on the larger cylinders and or stroked crank, ( need for balancing? ) and where does one get said parts? I would like to do the cold air induction from Sky Dynamics and their cylinder girdle, roller cam and adjustable roller rockers, EFII, other items are the piston and cam spray nozzles, case relief groves near cam caps, case stud O rings....also, would it be a good idea to buy a good core, to have all the little extra parts like fill tube drive gears ect?.........I am also trying to research all the little problems like the oil pump drive shaft-gear issue ect......Thanks, Bret.
 
Honestly Bret, while these Lyclone engines are awfully simple, there enough little gotcha's and tricks that I would seriously look at building with an experienced person (someone who does it all the time, not just whose done it once or twice, and has changed a jug....) by your side the first time - and maybe the second if you only do it once every ten years. It's not complictaed, it is just that there are little tricks that not only make it easier - they make it a better egine.

I wnet to Mattituc in New York and helped build my RV-8 engine - but that was 11 years ago and they're gone. I know somoene who went to Aerosport last year and helped as they built up his engine - so they might do it. You can do Superior's school and build your engine, but check to see if they have all the options you want.

When you add up all the special tools you might need to do the job right, and all fo the unique lubricants and sealers you'd want to have on hand, spending a little extra at a school is not that unreasonable. I'm going to the Lycoming school next February for a week (both the maintenance and assembly classes), and might be comfortable enough after that - and decades of working on them - to build my next one.

First Lyclone? Do it with experienced help - you're going to be flying behind it. With your family. Over the Sierra.
 
Engine Shop

I was going to build my own, but I went to a big local engine shop to ask about the YT connecting rods I had - they looked like they may have been overground on the sides - they weren't.

I asked about assembling the parts I had into an engine, and it was done off work hours by the senior assembler and QC inspector for about $500.

Heck, I spent around half of that amount getting a subscription to the latest and current Lycoming documents. :rolleyes:

If you don't get the certified paperwork - which you won't have for a DIY job anyway - paying an experienced builder may the easy way to go
 
Roll your own?

The real cost of this engine is getting all the parts specked out and on the bench ready to assemble.Having Lycoming or Major builder supply your new engine with run time and One to Two years of warranty.Don't forget the propeller,a fire breathing dragon like the one you specked out is limited to a couple high end(expensive)propellers that need expensive governors.You will be well into 60K+ territory.Now if you can convince Vans to sell you a RV-14 engine&propeller package,fly it for a wile then modify it till you have what you want.My guess is you wont need to.IMHO
RHill
 
Even a certified A&P cannot legally build up an engine unless he/she has previously built the same model under the supervision of an A&P who has done that particular model.
 
Build

Bret dont rule out the 200hp angle valve engine with the install of high compression pistons and a little polish and porting you will in the same range of HP for a lot less money great engine.
Bob
 
Bret, I think you would have to buy an engine like that from Aerosport Power or similar and do their owner assisted build. Putting these things together only takes the experts 6 hours or so and it goes so fast you wonder if you learn't anything.

If you want to build it yourself you need to look for a good core. You are not going to get roller cams, but I don't consider that a deal breaker. Aeros require a thick flange crankshaft without the lightning holes. If you want a constant speed prop you need a hollow crankshaft etc.

Another way to go is just buy a new crankshaft from ECI. The O-360 crank is ~$3600 from airpower or the O-370 crank (stroked) is ~$4900. That's what I did and I will have about half the cost of new in my engine. The local engine builder will help me assemble it next week.

Lots of builders want the best. The truth is that we only fly 100 hours a year. In some ways a new engine with 2,000hr TBO is a waste. I still think that the new engine from Vans is hard to beat. You can pay twice the price but you won't get twice the performance.
 
Mel said:
Even a certified A&P cannot legally build up an engine unless he/she has previously built the same model under the supervision of an A&P who has done that particular model.
Click to expand...

Only if you want the paperwork to make it a certified engine...
 
So, my questioning is not inline with the most basic of building techniques such as in what is the difference in a dry tq value as apposed to a wet one but more about the specifics of building a Lycoming air cooled engine. Like?.when measuring and adjusting the piston ring end gap, must you take into consideration of the cold set measurement of the cylinder choke? And are the rings coefficient of thermal expansion different than the rule of thumb of .004 per one inch in bore diameter used in NA water cooled engines ect?
 
Ring gap

Ring gap for the choke cylinders involves a minimum gap which is measured at top dead center. The gap is also measured near the bottom of the cylinders. So for the top ring you have two sets of limits, it is a relatively narrow range between the max gap near the bottom and the minimum gap at TDC.
This is all in the overhaul manual.
 
Required reading

The correct Lycoming Overhaul manual & Lycoming Table of limits.The correct parts manual for your engine.The list of AD's & SB's that reads like the Bible as to who begot who,some parts have changed part numbers many multiples of times.The Sky Ranch engineering manual. Great book with enough engineer speak to make DH happy. Manifesto: A Revolutionary Approach to General Aviation Maintenance.Until Walt retires and writes the definitive bible on RV maintenance,this is a timely as it gets. Every year Lycoming runs seminars at Airventure,its not hand's on but they do assemble and dissemble an engine and cover the basics as well as questions,Jim Doebler also teaches the course in Williamsport and NO,I asked,you can't bring your parts and build your engine at the school.How great would that be! Check out Speed with Economy. Ken spent years streamlining&testing his Mustang II with impressive results.

http://www.aopa.org/News-and-Video/All-News/2001/May/1/Airframe-and-Powerplant-(6)

Sky Ranch engineering manual: Operation, failure, repair, piston aircraft engines Paperback – 1991
by John Schwaner (Author)

Manifesto: A Revolutionary Approach to General Aviation Maintenance Paperback – July 7, 2014
by Mike Busch A&P/IA (Author)

Speed with economy: Experimental aircraft performance improvement Paperback – 1994
by Kent Paser (Author)
 
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So if everyone had just one trick to share, I think that would be very informative here, i cannot find a better place for this info than right here, I have read the entire ( what is your day job thread ) I know there is some serious talent here......I think the Lycoming started off as a good idea and has only gotten better over time with problems being identified and a fixed so to speak. I am sold on the EFII so I will be looking at the other aspects of the build. What is the most ingenious mod, fix, bulletin you remember?
 
6 Gun said:
Some engines use stretch rod bolts others use torq rod bolts.
Bob
Click to expand...

Again, only covered in a Lycoming SB, but this one is on-line -

http://www.lycoming.com/Portals/0/t...I 1458F (03-06-2012)/Connecting Rod Bolts.pdf

But you need the latest parts manual and part supercedure list to find out what is applicable to your engine model and your connecting rod part number.

The full library is here for $300 -

http://www.tdata.com/products-all/lycoming-manuals-all/lycoming-manuals-4-cylinder-engines.asp
 
I've been to Tulsa and the Barrett shop twice observing how they assemble engines and came away with the feeling it would take me a life time to do it as well as they do it, plus I don't have the equipment to for some of the process, like the device used to balance a crank shaft, which is FAA approved.

But then that's a perspective from not much experience re-building any engine beyond a lawn mower power plant. When one reads about the Wright Brothers and their friend building an engine to meet their needs from scratch, assembling one today from parts should not be too overwhelming, all it takes is a serious interest in doing it.

The challenge will be getting spun up on all the things that did not work over the past 75 years of Lycoming history.

There is an element of wanting to be able to do everything but sometimes there isn't enough time to do it all, from assembly of aircraft to painting to interior work to building an engine from parts, unless the learning process of it is more important than flying sooner than later. :)
 
My last crazy big block I built, I watched my machine shop ( who specializes in race engines ) balance the rotating assembly within 1 10th of a gram, not rocket science here.
 
bret said:
My last crazy big block I built, I watched my machine shop ( who specializes in race engines ) balance the rotating assembly within 1/10th of a gram, not rocket science here.
Click to expand...

While balancing is always good for any engine, it is not nearly as critical on a horizontally opposed engine that turns only 2700 RPM.
 
I agree Mel, to a certain extent, imagine a little weight at the small end of a rod, and then that gets matched up to one of the heavy pistons, and then gets thrown on the heavy crank journal, all those little grams add up, the way I have seen it done is, all pistons milled down to lightest piston, all rods get balanced big and small ends, bob weight of rod bearings, rods, wrist pin, retainers, pistons and rings, rod bearing oil amount, flywheel, HB get mounted to crank and dynamically balanced by adding Mallory or drilling counter weights, not that expensive in the scheme of things.
 
bret said:
I agree Mel, to a certain extent, imagine a little weight at the small end of a rod, and then that gets matched up to one of the heavy pistons, and then gets thrown on the heavy crank journal, all those little grams add up, the way I have seen it done is, all pistons milled down to lightest piston, all rods get balanced big and small ends, bob weight of rod bearings, rods, wrist pin, retainers, pistons and rings, rod bearing oil amount, flywheel, HB get mounted to crank and dynamically balanced by adding Mallory or drilling counter weights, not that expensive in the scheme of things.
Click to expand...

True. The way I balanced mine was to balance the piston/rod assembly as a unit.
My point is that you don't need to balance to 1/10 gram. If I remember correctly, Lycoming's limit is something on the order of 7 grams between the heaviest and lightest assembly. If you get to within a gram, that's a pretty good balance.
 
Well....I've done a few V8 Pinto and Vega 1/4 mile cars, even a turbo V8 Detroit 8.2 diesel+Allison in a pickup, but I think Ill stick to airplane engines in airplanes....for now....
 
See! constructive criticism! I won't drill my crank. thanks, as you re read my first post, first sentence, I have no aircraft engine experience, But, I still want to build my own engine. I am getting a feeling that this is one big secret or maybe there is not that much info to be gathered here, or, maybe folks are afraid to give advice in fear of a lawsuit? I see some have stated that they are not responsible for any advice given, is that a problem here, just asking....... here is one example of a Lycoming improvement. how many folks have this improvement, and how many do not? I'm sure there are many improvements out there but not much interest? https://www.youtube.com/watch?v=QDnPOE5lGEE
 
I found rebuilding my engine to be very simple following the instructions of two A&P friends and the Lycoming manual. That said, it is procedural in that you must be disciplined enough to make sure it goes together properly. You have to verify a number of measurements, assemble things in the correct order, use the appropriate sealants/lubricants for the specific applications, etc. Still, it is not rocket science.

If you do have a desire to build your own engine, I think your best bet is to find an experienced local engine builder and have him supervise your work. That way, you do the work, but know that the engine was assembled properly.
 
Bret, you are asking the right questions. Like you, I too had built up a number of engines before the one I currently fly behind but none of those were aircraft engines.

What I did was to find an IA who helped me put my engine together. Taking the engine apart and sending the pieces out for inspection takes a lot of time and will be a big savings, if you do that yourself.

I was stunned at the number of different lubricants and sealants needed for the assembly. Heck, even finding the silk thread was a challenge.

bret said:
My last crazy big block I built, I watched my machine shop ( who specializes in race engines ) balance the rotating assembly within 1 10th of a gram, not rocket science here.
Click to expand...
The problem with balancing the moving parts on an aircraft engine is you just can't take them to a grinding wheel or drill holes in them, like you might do on an auto engine. I know of one IO-540 that was "built up" by a known aircraft race builder and when a more reputable builder took it apart to inspect something, they found the guy had just run the connecting rods on a bench grinder. Pretty much the entire engine was trashed by the "expert".

While our engines are low speed engines, they are high torque, and that can snap parts.
 
bret said:
See! constructive criticism! I won't drill my crank. thanks, as you re read my first post, first sentence, I have no aircraft engine experience, But, I still want to build my own engine. I am getting a feeling that this is one big secret or maybe there is not that much info to be gathered here, or, maybe folks are afraid to give advice in fear of a lawsuit? I see some have stated that they are not responsible for any advice given, is that a problem here, just asking....... here is one example of a Lycoming improvement. how many folks have this improvement, and how many do not? I'm sure there are many improvements out there but not much interest? https://www.youtube.com/watch?v=QDnPOE5lGEE
Click to expand...

I, for one, am not trying to keep anything secret. But I remember a number of spots during an engine build with a master builder where he said "now the trick here is...." The problem is - I don't remember those tips - so I can't share them with you. Not because I don't want to. I don't build these engines all the time - maybe once a decade. I don't stay sharp flying a particular complex airplane if I don't look at it or touch it for ten years - and engine building (as has been said) is very procedural, just liek flying with complex systems.

The toher thign to rememerb is that if you mess up building a fire-breathing Chevy with lots of mods for your ground vehicle, you coast quietly to the side of the road. Airplane engines have to be extremely reliable, because when they quit, you are much worse off. Reliability is achieved through careful attentioon to detail and using processes and parts with long track records.
 
Another thing no one has mentioned is, pay attention to tolerances.
An air cooled engine that is subjected to a wide range of temperatures is built to somewhat looser tolerances than a liquid cooled engine where the temps are quite controlled.
 
If you bought a kit motor it would come down to verification and assembly. Pretty easy. If you rebuild a core you should send almost all lower end internals to good shops for rework. New cylinder assemblies would be valved, so ring set-up, valve lash and rockers would be the only thing on top. Stay near stock and your odds go up. Like Paul said, there are lots of assembly tricks, but the OH manual has most of them if you really look. Parts matching on the common models is pretty easy.
 
Been an ASE cert master tech in med heavy truck, auto, bus, engine machinist, alt fuel, X1, refrigerant, and advanced level L1, L2 the last three decades, one thing I've learnt is, you never know everything, in fact the more I learn, the more I descover What I don't know! So, What else has anyone seen worth mentioning? Rod bolt stretch preferred over tq? Anyone correcting rocker arm geometry with pushrods length and adjustable roller rockers? I read about an ocational valve sticking, any thoughts on why?
 
Another Great book added to Post #14

Bret, Its has been a little slow on here of late.At first you had me scratching my head as to "what are you up to?"So How about this an IO-360 angle with metal CS prop weighs what 360 to 400lbs an IO-720 has a listed weight of 595 pounds if you strip it down to crank,case,cam. use those new all aluminum cylinders,Carrillo rods,slipper pistons,Custom make the sump&intake out of carbon fiber&aluminum make it dry sump with the oil tank behind the passenger compartment for WB,you could knock off 200 pounds. Have Mr Cato work his magic on a 20 pound FP prop.Can you see the look on Vans face when he gets a load of this 400hp monster on the flight line at OSH.... Whats that noise,darn its the alarm clock,time to wake up come back to Reality.Your saving for an engine,right?Your a wrench,right? Buy a core,that's not a prop strike.Send everything out for yellow tagging.Build a reliable engine by the book.Your wife and kids need you and you don't want to hurt anybody else.You would never be happy till you build your own motor.How do I know this...Neither would I. So stop whacking the Hornets nest with that stick:)
 
WHACK! that's funny right there, I would not be happy with a 360.....my Ducati Diavel does 0-60 in 2.6 not fast enough, so I put nitrous on it, still not fast enough. my boat has a set of 496s.......a 540 had crossed my mind, but hey, a 720? Hummm............
 
No matter how fast you go,you still have cruise time in the air.On a Saturday morning flying to a breakfast with 5 other ships,different models,different engines.The big engines get there a minute or two ahead of the 0-320s and the Rotax is five minutes behind.In fact the Rotax guys benefit from in flight weather reports. I bought a firewall forward off a 66 Mooney and went from there,Crank,Cam,Case tagged,everything else new.Its added years to my 7a build.I couldn't get over the $25K hump the engine represents.The kicker was,I'm a wrench also,I would never be happy flying someone else's engine.You have the "Need for Speed" build a Harmon Rocket.The 7a has too many concerns/restraints to stray from Vans design.IMHO
RHill
 
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Engine

Just do what Bob Mills did put a IO-540 on the front and everything you can behind baggage compartment you get 300HP and the engine is not stressed and just loaf along at half throttle.
Bob
 
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