Lycoming IO360 Overhaul

you the airplanes you're watching are just one step in man's ongoing fascination with flight we at Sky were tech are thrilled by our good fortune to be part of the wonderful industry that supports the efforts of fliers everywhere through the years Todd Johnson and Phillip onic have met with many of you around the world conducting engine overhaul workshops they've had the opportunity to hear about your interests and concerns your enthusiasm led them to create videos outlining the overhaul procedures for several popular engines this video continues that dedication to providing you with the best information about your engine both Todd and Phil hope that this will translate into a safer and more secure feeling as you take off to experience that unique thrill man breaking free of gravity and moving across the sky while some of you are part of the growing up of home enthusiasts building your own craft others of you will be like many of the folks Phil and Todd meet around the country those who want to know when an overhaul is called for and what is involved like car owners some people take special care of their machines while others wait for a problem with an airplane maintenance means safety and peace of mind an overhaul is recommended when you've reached your tbo time between overall recommendation you've reached the manufacturer's time limit on an overall schedule or an unknown condition exists in an overhaul will ensure your comfort and peace of mind additionally preventative maintenance should be done to the manufacturer's specifications this tape deals with a lycoming IO 360 engine you'll note that we continually remind you to consult the manufacturers manuals for tolerances torques and other specifications different model gears model alterations and design tweaking won't change the basics of the overhaul but they will require you to maintain diligence in attending to the details so enjoy the tape whether you use it to rebuild an engine or just to become more familiar with your engine's internal workings it's great for honing your skills or just making you a more knowledgeable 88 our demonstration begins at Mattituck aviation the world's largest engine rig located on Long Island Mattituck aviation very generously allowed us the use of their facilities to perform our rebuilding while we're beginning with the reassembly you have to have completed certain tasks not covered here to reach this point at this facility engines are shipped in or actually flown in the engines are removed disassembled and everything is cleaned by water chemical brush or machine all tolerances are checked and parts are the broader specifications or if that is impossible they're discarded and replaced the reassembly centers around the crankshaft which we've mounted vertically on a fixed column a pan collar at the bottom is a convenience it helps with holding parts and tools the advantage of this mounting becomes apparent when we need to rotate the engine by hand to position the Pistons and perform other timing operations we also mount the crankshaft vertically so we can visualize the placement of the engines parts we understand that this is where the number one cylinder will be the number two cylinder and so forth this allows us to further visualize the relationship between parts such as the sum the camshaft etc while our engine doesn't have one some IO 360s use a counterweight system as a torsional vibration damper the counterweight is held in by counterweight pins a counterweight plate holds the pins in and it is secured by a snap ring the first step takes place as a sub assembly the left half of the crankcase is painted with an adhesive the adhesive is used to hold a 100% silk thread that actually works as a gasket this thread is routed to the inside of any bolt holes so that no oil can escape through the bolt holes or the parting surfaces the silk thread is left long so that it'll meet and be a continuation of the nose seal that will be used at the crankshaft opening next we put in the bearing inserts there have been updates in a few different styles of this part so refer to your parts manual for specific parts numbers now we put in the tappets which actually give movement to the valvetrain as with most assembly steps everything is lubricated the camshaft is now fit into the crankcase all rings are fit into the both depressions so that the crankcase halves seal when brought together the front main bearing can be for peace or to peace if your engine uses a four-piece main bearing it is placed in the same manner as the center and rear main bearings our engine uses a two-piece front main bearing which is put in differently it must line up with the dowel posts in the crank case position it while the case is open and with a pencil mark the spots on the bearing where it must meet the dowels this will allow you to more easily position it later the crankshaft seal is now placed around the crankshaft and will be coated with adhesive when the crankcase halves are brought around it the crankier is now positioned on the top of the crankshaft there's an ad air worthiness directive out on this part so this plus the manufacturer's service bulletins must be strictly adhere to the process includes tapping down and placing of the bolt with a lock tab this is then torqued again paying careful attention to the manufacturers bulletins there's an inspection in this area with a feeler gauge any part of the gauge which goes under at these points would warrant taking it off and an inspection being done the objective here is to get the gear down in the counter bore and square with it if it's not flush and flat you could have a lot of trouble down the line and in the air we now assemble the connecting rods with the correct bearings the size need for the crankshaft a crank shaft can be reground to - tolerances rather than being replaced this must then be accommodated by correctly matching the bearings the connecting rods and crankcase are numbered and you always keep the corresponding numbers together 1 2 1 2 2 2 etc we now see why we originally spoke of mounting the crankshaft vertically for purposes of visualizing the final assembly the vertical mounting and raised numbers are both aids in this visualization process the connecting rods are assembled on the crankshaft with the numbers away from where the camshaft will be and toward the sump side we now lubricate the bearing areas the thrust surfaces and the threads we now face the crankshaft and oriented so the lower or number 1 piston is extended to what would be called top dead center or full firing position by being in this position the rest of the engine will sequence easily as we proceed we now assemble with the i/o 360 bolts are not torqued they're stretched tightened until they reach a specific length we now have reached a point where we have two sub assemblies which we're about to be joined after joining them we're not going to be able to go back and separate our work so here we suggest having a knowledgeable friend inspect your work so far or walk away for half an hour or so and come back with a fresh perspective and review what you've done this is a technique we'll be suggesting at several points during this rebuilding process now being satisfied that all is correct at this point we're ready to join the sub assemblies this means lubricating all the bearing points and thrust surfaces the front main bearing is lubricated and placed at the front main crankshaft journal again we can visualize knowing that the crankcase will go on here the bearing will go here since this is a two-piece front main bearing and thus we marked it with a pencil we can line up the dowel holes correctly will place adhesive on this nose seal and on the receiving part of the crankcase this is a contact cement recommended by the manufacturer will adhere when the halves are brought together and since it's a wearing part it gets lubricated this is done because the crankshaft can grab the sealant spin it causing crankcase damage we now position the crankcase half over the extended number two cylinder the bearing is adjusted to fit correctly over the dowel markings this means positioning rotationally and vertically an extra set of hands will be necessary in leveraging the crank case if the dowel holes did not align when you tighten the crank case the result would be a pinched bearing that would not allow the engine to rotate the seal is now raised into position keeping in mind to rotate the split so that it does not align with the crankcase parting seems a 10 o'clock or 2 o'clock position when viewed from the top this way the scene will not be aligned with the crankcase halves with no contiguous seams there are less easy paths for potential oil seepage to follow as a rule we will always avoid allowing seems to line up you can see a machined groove in the crankcase into which the seal can set there are several styles of seal if this doesn't describe yours refer back to your manufacturers manual for installation instructions a gauge must now be taken to make certain that there is clearance between the crankcase and the part of the crank shaft called the oil slinger the oil slinger is merely a saucer edge near the other side of the thrust face that by centrifugal force induces oil to go out and back into the crankcase this saves the seal from being excessively oiled and prone to sea pigeon leaks the crankcase is levered to accommodate the manufacturers recommended feeler gauge clearance without this clearance this is another spot that would be subject to immediate wear if all steps so far are correct you'll notice that there is sufficient crankcase in play the left half of the crankcase is now fitted this also requires a second set of hands bolts are put in left to right as per the manufacturer's recommendation with a washer on both the nut and bolt head sides an internal lock washer safeties that nut in place as you continue around the crankcase your assistant should lightly hold the halves in place the crankcase at this point should be viewed as a hole machined part and the tolerances established must be scrupulously maintained the bolts are lightly tightened so the crank case may be aligned by the through bolts we check that there's no binding that the crank case and play still exists and that the camshaft turns we can now put in the engine through bolts these bolts seal align and hold the halves together and hold the cylinders they must be hammered into position they are neck down in the middle so that while the ends are sealed the middle can still expand and contract with the heat of the engine and still be a holding force a screw on cap allows the bolt to be struck with a hammer but care should still be exercised since excessive force can still cause thread damage inside the protective cap there are eight bolt positions the lower bolts do not have a cylinder on each side so a spacer takes up the length the top two bolts are actually studs built into the crankcase right half and the left side fits onto them these bolts therefore need no spaces on the built inside the four Center bolts are hammered in is described you can visually gauge the correct placement and later nuts on either end can pull the bolt through or back to whatever position is desired the remaining crankcase nose bolts go through the o-rings that we have glued into the recesses provided for them use a light grease to carefully screw these bolts through the o-rings are good seals but they are silicone o-rings and will tear to bits if you try to screw a dry ball through them the light oil prevents this if you see any o-ring material at the exit end stop and go back and replace the o-rings any o-ring damaged all but guarantees an oil leak by the way any disassembly at this point requires a replacement of any sealing part such as the silk thread nut and torque the bolts as per the manufacturer's recommendation we will now bolt and torque the through bolts to the specifications in the manufacturers manual this uniform crush on the case seats all the bearings and rounds up everything we now check for movement making sure there's no binding since the case is now as tight as it's going to get we can now put in the remaining smaller bolts torquing them three bolts go in the some side and they are safety wired all internal parts have some type of locking device to prevent vibration aware front seating them and thus causing unseen internal damage of course these bolts are tightened to the recommended torque the 3/8 stud that holds the crankcase together at the gear end of the camshaft has to be torqued and wired earlier models may have a complete through bolt we now address the gear section gear idler shafts are positioned and locked plates are put on for safety they're torqued and then to prevent bolts from loosening and possibly slipping into the engine the ends are bent up gali plugs are now installed we now position the gears we must reference back to the number one cylinder which we want extended to top dead center this is because we want the crankshaft to be timed to the camshaft this allows the valves to operate properly depending on where the piston is in the cylinder we extend the number one cylinder we locate the timing marks on the camshaft those two dots there and we locate the timing marks on the crankshaft gear the timing gear drives the camshaft drives the magneto and has an eccentric a cam which drives the fuel pump the timing gear has marks which we match to the camshaft and crankshaft timing marks we match everything and the timing gear falls into place the next gear turns the magneto and while it is similar to the preceding timing gearing that it has timing marks it's not time to anything else so the marks are of no consequence this is the tachometer drive shaft it's attached to the camshaft a tachometer cable will be attached to connect it to the instrument panel where it will tell you the engines rpms revolutions per minute it's held in by a snap ring be sure to rotate the snap ring opening 90 degrees to the tach pin opening again we never allow openings to line up this is your oil pump it consists of the housing and to impellers with a drive shaft these are assembled use of a heavy lubricant is important here for the initial priming of the system this oil pump assembly is attached to the internal side of the accessory housing by means of three Castle nuts and three plane washers which are torqued to the manufacturer's specifications and safety wired when joined the protruding shaft engages the crank gear a seal is applied to the decameter drive shaft housing next we install the fuel pump push rod which is needed to drive the fuel pump lever we've now reached one of those points where we're about to close something up and we should have our knowledgeable friend check our work while we step back or step away for a break refreshed we can review what we've done with clearer eyes and move on we now come to the accessory housing blue silicon will be used at several important junctures one is here where the silk thread comes out of the crankcase no matter how well mill the halves are a slight Valley could form with the halves but sew a drop of sealant is placed and the thread is bent over the accessory housing now gets an accessory housing gasket use a sealant recommended by the manufacturer now all the gears and shafts are lubricated now as you're ready to position the accessory housing you want to be sure that the drive shaft is aligned with the crankshaft gear that will be driving it by holding the shaft in position with your hand under guide the housing on and with this for basic alignment shifted slightly until the whole unit seats itself sort of snapping into place never seat this by screwing down the bolts anything more than light tapping would suggest something's out of line or incorrect don't force anything at this point put the housing bolts in and torque them to the manufacturers settings and do it in the correct sequence the prop governor drive gear is lubricated and installed in the prop governor drive housing a thrust washer is installed and the assembly is held together with a snap ring it's mounted on the accessory housing with a gasket a pin alignment assures proper assembly we're now ready to attach the oil sump the oil sump is a large unitized piece that has air manifold tubes that allow air induction and lead to where the fuel servo will be the body will contain the engine oil when the sump is fitted to the crankcase you can see that splash oil will flow over the gears we've lubricated providing for their ongoing lubrication a small hole in the sump allows for placement of a pre pump oil screen tube this is a filter which precedes the oil pump which in turn is followed by the oil filter it screens out large particles which could clog the oil pump or filter and hinder oil flow during an oil change the screen is cleaned and the oil filter is cut open the type and size of material found can give accurate clues as to what is going on in the engine the pre pump screen is fitted with a crush washer during the correct number of degrees and safety wired when mounted in joining the sump to the crankcase we now see that the accessory housing gasket was left long on the crankcase this is done to accommodate any variation and allow for cutting to correct size if everything is okay these can now be trimmed off and dots of blue silicone applied to the three spots where joints a car on the face of the joining surfaces adhesive is applied the gasket is positioned and the sump is placed bolts are torqued to the specifications and in the recommended order the prop governor tube attaches from the prop governor pad who are fitting in the crankcase peanuts are tightened and hold it in place with several braces this engine can take an oil screen or an oil filter the oil filter spin-on adapter is easily attached it gets a gasket is adjusted to position bolted and torque to specifications the adapter has two inputs one is for a temperature probe which operates the oil temperature gauge on the instrument panel the other opening houses a Verna therm bypass valve this thermostatically self operated valve exposes a hole to the oil cooling system when the Virna therm heats up it expands and covers the hole allowing oil to flow through the oil cooling system this is a simple mechanical system which cannot be worked on or adjusted when it no longer works it's thrown out and replaced the Verna therm is simply screwed in and safety wired we've now come to the vacuum pump drive adapter housing the vacuum pump which is outside the scope of this tape is driven by this drive and creates vacuum necessary for the operation of some of the gauges on the instrument panel the housing gets an oil seal a thrust washer which prevents it from eating itself and the drive gear they fit to each other and are then positioned through the gear housing to be driven by the rotation of the camshaft the unit will seat itself and can only go in one way a small internal oil passage allows oil to lubricate the shaft while it's in operation there is also a small protruding pin which guides correct positioning don't force anything the oil pressure relief valve is now screwed into position this valve is a spring-loaded ball the spring holds the ball against the camford relief hole excess pressure pushes the ball off the opening and allows the pressure to be relieved you can create any pressure relief level you want by using various combinations of washers and springs your manufacturers guide will tell you how to do this the valve is screwed in with a crush washer and safety wired the oil pressure fitting is now installed the dipstick housing is now screwed into the crankcase it's fitted with a gasket and safety wired and oring seals the upper stick end of the housing which is applied when the engine is installed this is the stage at which we generally paint the engine over time we've developed high-tech methods of protecting the internal engine from splattered paint be creative you'll find the means to block all the engine openings we've now reached the point of installing the cylinders reconditioning cylinders especially work requiring special skills and equipment we don't cover that here when the engine was dismantled the cylinders were refurbished the guide seats and valves have been replaced and clearances reset to the manufacturer's specifications and tolerances they also have been repainted you can now check the cylinders check piston skirt size to the barrel clearance cylinders and pistons are separate pieces and both come in over sizes we remove the ring and insert it into the cylinder to make sure that the ring gap with a ring ends but is to the manufacturers tolerance the Rings are then replaced correctly with the numbers up we're now ready to assemble an o-ring sits at the base of the cylinder is an oil seal if your i/o 360 has a cooling nozzle this is the point at which it is installed it is screwed in and torqued the piston is symmetrical and can go in rotationally up or down we've numbered each piston so that with any engine work the same piston will go back into the same cylinder in the same position anticipating avoiding any individual cylinder characteristics or quirks causing changes during where we now put in a full floating wrist pin which is held in or centered by wrist pin plugs these plugs may protrude at times and touch the cylinder walls but not to the detriment of the engine the cylinders are now ready to be positioned care is taken to rotate the ring brake gaps approximately one third of a turn off of each other this again is just an added precaution to eliminate a direct path of escape for exhaust gas from the cylinder a ring compressor compresses the Rings to allow them to slide easily into position the cylinder is now positioned bolted and torque as always to manufacturer's specifications we now begin the installation of the valvetrain these hydraulic units are all the same but they're milled units they come apart for cleaning but if anything happens to either piece throw them out don't try and match them with other mates or you'll have a rough ring engine the unit is not full of oil now to allow for what we call a dry tappet which allows the internal spring to work correctly oil would create a false resistance and give a false indication of the dry tap at clearance the unit sits in the tappet we installed with smooth hole in spring out a lifter cup is now installed which is nothing but an adapter going from a flat surface for the spring end to a concave surface to meet the push rod all were lubricated before installing the pushrod tubes are installed with seals at each end a spring supplies pressure to secure the tube in place a rotor cap is placed on both the exhaust and intake valves the push rods are installed the intake and exhaust rockers are cast differently so they fit their corresponding position a thrust washer is installed and a rocker pin holds the assembly together the dry tappet clearance is now checked with a go/no-go gauge to meet the manufacturer's specifications go/no-go means that the minimum side go should fit and the maximum side no-go should not fit any misfits and the clearances are adjusted by changing the actual rod the manufacturer makes rods of four lengths and a go/no-go means you change rods to get the correct fit the rocker covers can now be put on consisting of simply a gasket and rocker cover screws the i/o 360 has a gasket cover to hold the rocker shaft in place it's nutted and torqued the intake pipes are installed the sump end is sealed with an o-ring the cylinder end has a gasketed flange that is bolted and torqued drain back tubes are now fitted these tubes are shaped very specifically to the course they must follow so they're hard to mix up each has a rubber connector and a couple of clamps each slides over a fitting in the crankcase and is clamped each is self sealing at the cylinder side and is sealed with a B nut oil that settles in the cylinders simply drains back to the sump area through these tubes the fuel manifold is now attached to the crankcase its function is to evenly distribute fuel to the cylinders the fuel injection nozzle is installed and torqued the fuel line is installed and attached to the pushrod tube by means of Adel clamps we now want to rotate the engine to get piston number one in full firing position placing your fingers over the spark plug holes simulates compression as you turn the engine you can hear the compression come up when we've ascertained this spot we now place the starter gear support in the dowel holes at the base of the crankshaft each engine has a plate on it which indicates the firing point and firing sequence this engine says 25 this means that the spark should occur 25 degrees prior to the piston being fully extended this spark is timed to two Magneto's one left and one right both are the same except for one thing since most engines begin firing with the left side the left magneto has a spring-like caller called an impulse coupling that retards the first sparks when an engine is first started it must build to its rotational speed the normal firing is timed for an engine that has reached normal speed these first sparks will fire to more accurately match the initial rotational speed fly weights pull in the impulse coupling which allows the engine to go right back to 25 degrees before top dead center were at normal runs in positioning the Magneto's a spacer fits on the opening of the left magneto to take up the space created by the impulse coupling hanging down the right magneto not having this piece does not require a spacer in placing the Magneto's we must line up the sparks for the number one cylinder each magneto has a L and an R this asks for the direction in which the magneto will rotate and fire this is a left rotating magneto so we place a thin pin in the L hole side and slowly rotate the magneto until the pin drops further indicating it's locked into the correct number one cylinder position slight turning indicates it's in position by a slight wobble but don't turn too hard or bring excess pressure to bear here since the pin might Bend and can cause expensive problems inside the magneto that you can't see or learn about until it's too late a coded gasket and the Magneto's are placed the magneto can go in any manner that allows the gears to mesh but consideration for any possible interfacing with the engine mounts may make you want to rotate it to a more can be in position the other magneto was also left rotating so it spin is placed in the same manner a gasket is again coated and the magneto placed and the pins removed we're pretty on target as far as timing is concerned that the number one piston is a top stroke and the Magneto's will fire correctly but it's now time to fine-tune the magneto clamps are put on finger tight for fine-tuning and will be tightened later we want the points to be just opening because that's when they release their energy to the cylinder a magneto synchronizer is attached to the Magneto's and the pins are removed the lights on the gauge will go on when the points on each magneto open we want to be sure that both occur at the same time this means both lights must light at the same time the leads from the synchronizer go where the leads from the cockpit will be we turn the engine to 25 degrees before top dead center to see how close the lights are to going on together you're allowed a certain tolerance as per the manufacturer we can hear each one click in on the synchronizer and they're almost exactly together which is fine adjustments if they're necessary are made by rotating magneto forward or back to more accurately match the two sparks to accepted tolerances now you can torque the magneto clamps and adjust the engine for synchronization the ignition harness is generally attached at the aircraft since ignition wires are often snaked through the air frame and therefore left in position if the cap is removed or when rejoining them at the frame be careful to match all the numbers left side to left side cylinder 1 to cylinder 1 and so forth spark plugs are lubricated on the threads and torqued in place as per the manufacturer's specifications the starter is simply attached and bolted down and if your engine has an oil filter instead of an oil screen the oil filter is screwed on torque and safety wired the fuel servo has a gasket and is installed on the sump this servo monitors fuel and air flow this is the point where you'll reinstall your engine a facility such as the one that we're using has the advantage of the test site so we can easily make any before reinstalling all tests being done we're ready to fly and that's what it's all about but thrill and joy of aviation soaring above the earth secure the knowledge that we've made the effort to make our time in the air safe and trouble-free our skills as pilots allowed to shine because our engine is dependable Mattituck Aviation has earned a reputation for excellence throughout the world attention to detail customer service and handcrafted tradition has earned us that reputation whether you need repair rebuilding a replacement matter tux customer minded staff with over 500 years of combined experience can serve you whatever your engine needs may be our extensive parts inventory complete machine shop and direct factory support guarantees that we can give you unmatched service from the firewall forward whether your aircraft is lycoming or continental powered we offer only the finest in quality value and warranty our experience having produced over 10,000 engines continues to earn our reputation call write or visit us anytime our doors are always open Mattituck aviation corporation one eight hundred sixty four six six eight zero

Channel: Aviation Videos

Views: 451,228

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Id: n-26eqLc4pQ

Length: 36min 34sec (2194 seconds)

Published: Wed Apr 13 2016