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First engine start: do/don'ts

AX-O

Well Known Member
All,
As I prepare for my first engine start, I have been reading the archives via the search function. I have not come across a post that specifically addresses the precautions you should take. There is info throughout post but not a central location. Maybe I did not use the search function correctly.

I would like to know how to prepare myself and how to address the first engine start on the test plan.

Some of the mitigations I was planning on using are:

Do
-break engine in on dyno
-fill oil cooler and oil pressure line with oil.
-purge fuel lines/oil lines.
-A qualified person manning a fire extinguisher.
-Tying my tailwheel to my truck.
-Having a camera pointing at my engine display for post data analysis.
-Closed canopy.
-Not a lot of fuel in the fuel tanks.
-Cowling off.
-engine plenum on for cooling.

Don’t
-Don’t run engine for a prolong time.
-Don’t go above XXX temp on CHT
-Don’t go above XXX RPM

What else should I be thinking about? Thanks for any guidance of help you can provide.
 
Directly from The MAN!
Hope this helps!This is how I would do the initial runs. I have used this procedure thousands of times with complete success.
Good luck,
Mahlon

CYLINDER RUN-IN INSTRUCTIONS FOR CHANNEL CHROME,
CERMICROME, AND CERMINIL BARRELS

1] Install mineral oil in ALL normally aspirated engines and all Teledyne Continental turbocharged engines. Install AD oil in all Textron Lycoming turbo charged engines.

2] Start engine, run at 800 R.P.M.'s for three (3) minutes, shut down, check for leaks.

3] Start engine, run at 1,000 R.P.M.'s for three (3) minutes, shut down, check for leaks.

4] Cowl aircraft.

5] Start engine, run at 1,200 R.P.M.'s for three (3) minutes, shut down, park into wind.

6] Start engine, run at 1,400 R.P.M.'s for three (3) minutes, shut down, park into wind.

7] Start engine, run at 1,400 R.P.M.'s for five (5) minutes, run up to full power, check all engine parameters, retard power to 1,000 R.P.M. for one (1) minute, shut down.

8] Check for leaks The engine has now had it's Test Cell run time and is ready for other ground runs, taxi tests, adjustment runs, etc., observing the precautions from the post

All runs should be made into the wind.

At no time during these runs should CHT exceed 350F.

Between all engine runs, allow adequate cool off time.

Before proceeding to next run, you should be able to hold your hand on a rear cylinder head for three to five seconds.

CYLINDER RUN-IN FOR STEEL,
NITRIDED OR REBARRELED CYLINDERS

1] Install mineral oil in the engine.

2] Start engine, run at 800 R.P.M.'s for three (3) minutes, shut down, check for leaks.

3] Start engine, run at 1,000 R.P.M.'s for three (3) minutes, shut down, check for leaks.

4] Cowl aircraft.

5] Start engine, run at 1,200 R.P.M.'s for three (3) minutes, shut down, park into the wind.

6] Start engine, run at 1,400 R.P.M.'s for five (5) minutes, shut down, park into wind.

7] Start engine, run at 1,400 R.P.M.'s for ten minutes, shut down, park into wind.

8] Start engine, run at 1,400 R.P.M.'s for five (5) minutes, run up to full power, check all engine parameters, retard power to 1,000 R.P.M. for one (1) minute, shut down.

9] Check for leaks The engine has now had it's Test Cell run time and is ready for other ground runs, taxi tests, adjustment runs, etc., observing the precautions from the post

All runs should be made into the wind.

At no time during these runs should CHT exceed 350F.

Between all engine runs, allow adequate cool off time.

Before proceeding to next run, you should be able to hold your hand on a rear cylinder head for three to five seconds.

This is some information on running after completing the above schedule:
Knowing this crucial information allows us to make practical decisions regarding ground runs and flight profiles from the new or newly overhauled engine point of view.
To put it simply, if we get the ring to cylinder interface too hot from too hard of running, lack of cooling or another reason we will glaze the cylinder walls and prevent actual break in from occurring. Because, we are dealing with multiple independent cylinders on the engine, these conditions can happen to one cylinder, all cylinders or anything in between on the same engine. So our job above all other aspect of engine operation during the break in phase, is to keep the cylinder's as cool as possible. If we do this we will not have any problems or issues with the engine as far as break in goes. During any and all ground runs we should limit the duration and actual temps we encounter to prevent glazing from happening. We tell our customers to keep all ground runs less than 10 minutes. Don't run the engine above 2000 RPM unless you are doing a momentary full power check, high speed taxi tests or actual take off runs. If the CHT goes above 350*F or the oil temp goes above 180*F at any point during the 10 minute max. duration ground run, or at the expiration of the ten minute time limit, that run should be terminated. Then, park the aircraft faced into the wind and allow the engine to cool, until you can place your hand on the cylinder heads and barrels for 5 seconds without hurting or burning you hand and the cylinders feel relatively cool to the touch. After the engine has cooled, continue with the last run where you left off. Obviously, from what we have learned about temperature, running the engine more conservatively will not cause any problems and may even help the break in process but operating within these restrictions, on the ground, should prevent any glazing issues. These limitations apply to an engine that has had a test cell run before any ground runs are attempted. If your engine hasn't had any test cell time, then I can supply you with a ground run schedule, to replace the test cell run, which can be performed on the aircraft. If you want or need that information, just email me privately and I would be happy to send it along.
When it comes time to fly the aircraft, once again we want to observe the ground run rules, for taxi and warm up. Once we are ready to fly, we want to use full power for take off and initial climb and then we want to reduce power to climb power(normally around 85%) until we reach a safe altitude above the airport. Keep the climbs, as flat as possible, to maintain as much cooling as possible. Remember that heat is our major enemy and we can control that with climb speed. After establishing an appropriate altitude, reduce power to 65% to 75% ( preferably 75 % if speed restrictions will allow it). If we see temps, exceeding 15% of our ground run limitations, in initial flights, we should reduce power to control those temps and land the aircraft. Then, double check all cooling associated equipment, repair as necessary if you find a defect, let the engine cool off and fly it again, taking up from where you left off, observing the same restrictions. The first flight shouldn't be any longer than 10 or 15 minutes maximum, even with good cooling that would allow a longer flight. The first flight is a "test flight" and after landing you should do a through visual inspection of the engine and its installation, for leaks and any other operational issues like interference fits that showed up under power, chafing of lines etc. After the first flight issues are checked, we are ready for further flights under the same ground run and flight restriction's we have been observing. The key issue once again is heat. If we control the heat by power setting, airspeed, step climbing or any other means at our disposal we will not glaze the cylinders and we will successfully break the engine in. If we operate the engine at too low of a power setting, to seat the rings, we will not harm the engine or the eventual break in process, unless we develop enough heat to glaze the cylinders. In another words, operation at a low power setting, isn't a deterrent for break in unless we have the heat.
The rest of this article is in part II
 
I strongly urge you to tie it off to something other than a vehicle. I've heard of several instances of aircraft that got destroyed by the vehicle being driven while aircraft was still attached.
 
I strongly urge you to tie it off to something other than a vehicle. I've heard of several instances of aircraft that got destroyed by the vehicle being driven while aircraft was still attached.

Maybe tie the truck keys to the strap connecting the vehicle and the plane?
 
Borrow someone's optical tachometer if you're monitoring rpm with an EFIS/EMS Sometimes it takes a trial run or two to determine the proper RPM factor that you'll need to select in the setup menu.
 
Thank you for the replies thus far. Keep them coming. Just so we don't start drifting from the original intent.

Only things to do or not do before/during the first engine start. Thank you.
 
Oil pressure

I suggest pull a plug from each cylinder and spin the engine until you see oil run from a removed oil galley plug. You can do it with the starter or by hand. Probably take 30-40 turns before you see oil unless it's been run before. I like the comment or fill the cooler hoses also, especially since you can flood the oil pump from the oil cooler "out" hose while your at it.
Also if it's been sitting a long time, while the plugs are out take a straw and fill it with oil, then blow that oil up into the cylinders with compressed air while the Pistons are down.
Tim
 
This looks great, but it looks like it applies to a new/rebuild that hasn't had a test stand run-up. My factory new IO-360 had a run-up at the factory, with a test results sheet. How would I do it differently for my first run-up on the aircraft?


Hope this helps!This is how I would do the initial runs. I have used this procedure thousands of times with complete success.
Good luck,
Mahlon

CYLINDER RUN-IN INSTRUCTIONS FOR CHANNEL CHROME,
CERMICROME, AND CERMINIL BARRELS

1] Install mineral oil in ALL normally aspirated engines and all Teledyne Continental turbocharged engines. Install AD oil in all Textron Lycoming turbo charged engines.

2] Start engine, run at 800 R.P.M.'s for three (3) minutes, shut down, check for leaks.

3] Start engine, run at 1,000 R.P.M.'s for three (3) minutes, shut down, check for leaks.

4] Cowl aircraft.

5] Start engine, run at 1,200 R.P.M.'s for three (3) minutes, shut down, park into wind.

6] Start engine, run at 1,400 R.P.M.'s for three (3) minutes, shut down, park into wind.

7] Start engine, run at 1,400 R.P.M.'s for five (5) minutes, run up to full power, check all engine parameters, retard power to 1,000 R.P.M. for one (1) minute, shut down.

8] Check for leaks The engine has now had it's Test Cell run time and is ready for other ground runs, taxi tests, adjustment runs, etc., observing the precautions from the post

All runs should be made into the wind.

At no time during these runs should CHT exceed 350F.

Between all engine runs, allow adequate cool off time.

Before proceeding to next run, you should be able to hold your hand on a rear cylinder head for three to five seconds. !
 
fire precautions

you say qualified person; great.

also ensure you don't just have the ABC chemical from the hangar.
if it HAS to be used, I've heard this can total the aircraft due to the corrosive effect.
Halon is best ($$$$) but at least a B-C reduces the corrosive ingredients.
(you might want to look this up.....I am not an expert. I have never put out a fire. I have started a few.)
 
Sid, in the case of a run-in but not broken-in engine I would do this...

Start engine with aircraft tied down. Run for 3 minutes at 1000 RPM or less. Check for charging. Adjust idle. Do not get the CHT above 350. Shut down, check for leaks and let it cool.

Start engine with aircraft tied down and FLAPS UP. Let it warm up and check prop, mags and full power RPM. Never above 350 CHT. Shut down, check for leaks and let cool.

Cowl aircraft. Start it, check the basics and fly it.

I personally would change the oil, check the filter and screen between the first and second run but I think most people would find that overkill.

Edit: None of this accounts for aircraft checks. I would think you could check the brakes and steering in test 1 if you didn't tie it down.
 
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I suggest pull a plug from each cylinder and spin the engine until you see oil run from a removed oil galley plug. You can do it with the starter or by hand. Probably take 30-40 turns before you see oil unless it's been run before. I like the comment or fill the cooler hoses also, especially since you can flood the oil pump from the oil cooler "out" hose while your at it.
Also if it's been sitting a long time, while the plugs are out take a straw and fill it with oil, then blow that oil up into the cylinders with compressed air while the Pistons are down.
Tim

I would not do this, you're not lubricating the cam for all those rotations.

There is a way to prime the oil system (filling the hoses, cooler, pump, etc) with a power drill turning the oil pump before start, I just can't tell you how.
 
I suggest pull a plug from each cylinder and spin the engine until you see oil run from a removed oil galley plug. You can do it with the starter or by hand. Probably take 30-40 turns before you see oil unless it's been run before. I like the comment or fill the cooler hoses also, especially since you can flood the oil pump from the oil cooler "out" hose while your at it.
Also if it's been sitting a long time, while the plugs are out take a straw and fill it with oil, then blow that oil up into the cylinders with compressed air while the Pistons are down.
Tim

In the past, I pull the bottom plugs then motor the engine with the starter till I see oil pressure. Plugs then go back in and I start the engine.

I see no need to pull an oil galley plug. The pulled plug now becomes the path of least resistance and possible not getting oil to a bearing that needs it. It is also just something to go wrong later. (leak or forgetting to put it back in)

The cam is splashed lubed and most builders will coat it with grease for assembly. Being concerned is good but no different than starting the engine after it is parked overnight.
 
One way is disconnect the Oil Pressure pipe, turn until oil comes out. Effectively same as "seeing Oil Pressure" and also fills that line.

As above, be clear "why" or "what" you are achieving by running engine on the airframe prior flight. If the engine has been bench run, then engine has proven itself, what you need to check is the installation.

My view (which will differ from many I am sure!) is run it long enough only to check the instruments/controls work, the VP Prop works (might need 1500 RPM?), no leaks etc. I would be cautious about full power runs - I am happy to cover that with a rejected takeoff prior first flight.

I would also not run engine much above ~1500RPM without cowls on.
 
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I would not do this, you're not lubricating the cam for all those rotations.

There is a way to prime the oil system (filling the hoses, cooler, pump, etc) with a power drill turning the oil pump before start, I just can't tell you how.

You can do this on some automotive engines by removing the distributor and using a keyed shaft to turn the oil pump, but not on a Lycoming since the oil pump is driven by the cam gear.

I personally never run a new or overhauled engine with the cowl removed, and I very rarely run an in-service engine without the cowling either. Running the engine without the cowling does not accomplish anything that cannot be done with the cowling on, it just takes a few extra seconds to open the cowl to inspect the engine or make adjustments.

There are some very good information in this tread.
 
Crank gear not cam, but your right, no way to turn the pump without dragging the engine along with it. You can build a "pig" and pressurize it if you want, but it's not really necessary, especially if you flood the pump first.
Something else not mentioned yet is to run it at 1000 rpm or so to oil the cam, it relies on oil thrown off the crank.
Tim
 
Crank gear not cam, but your right, no way to turn the pump without dragging the engine along with it. You can build a "pig" and pressurize it if you want, but it's not really necessary, especially if you flood the pump first.
Something else not mentioned yet is to run it at 1000 rpm or so to oil the cam, it relies on oil thrown off the crank.
Tim

Yes, Crank gear is correct, sorry. Very good point regarding minimum RPM for camshaft lubrication. Sometime in the past I read some data from Lycoming that indicated the camshaft did not recieve "full" lubrication below 1200-1300 RPM if I remember correctly. That is not to say that the cam will eat itself if the engine is idled below this speed, but i recall 1000 RPM as the minimum reccomended ground speed. I will try and find this information and post it.
 
I made a pre-oiler from PVC pipe, some fittings and clear hose.

Essentially it was a 3" by 5' piece of pipe. The top had a compressed air fitting and the bottom had a ball valve hooked to clear tubing.

You fill the pipe with oil. Hook the clear line to the 'in' oil cooler fitting on the engine. Hook another piece to the other oil cooler fitting so the oil doesn't go all over your new install. I put the air regulator on about 50 PSI and then open the valve. Have someone watch the oil pressure gauge and they should see 35-45 PSI just about the time oil starts spitting out the exit tubing. This is why clear is best.

After that I hook all the cooler lines back up and spin the engine over with the starter with no spark plugs in it until I see oil pressure on the gauge. It's almost instant. I feel that is a primed engine ready to start. Cam may be dry but the mains and pump should be ready to start slinging oil.

This is probably 100% overkill but I feel it's the correct thing to do.
 
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In the past, I pull the bottom plugs then motor the engine with the starter till I see oil pressure. Plugs then go back in and I start the engine.

I see no need to pull an oil galley plug. The pulled plug now becomes the path of least resistance and possible not getting oil to a bearing that needs it. It is also just something to go wrong later. (leak or forgetting to put it back in)

The cam is splashed lubed and most builders will coat it with grease for assembly. Being concerned is good but no different than starting the engine after it is parked overnight.

I agree with Gary. Every half decent engine builder uses plenty of whichever assembly lube they prefer. The cam is well lubricated for the few rotations it will take for the oil pump to fill the system. Pull plugs, engage starter and wait for oil pressure. Doesn't take long.

First start...so exciting! Congrats!
 
Protocol

Mahlon Russell is one of the very best small aircraft engine experts in the US. His instructions say to run the engine for three minutes at 800 r/m with the cowl off. That is EXACTLY what I am going to do. This run is not going to hurt the cam and there is no danger in running the engine at low speed with the cowl off.
With all due respect, most of the people with "better ideas' are back benchers with perhaps 1% of Mahlons experience.
 
Lots of discussions about the engine which are good.

I am still interested in other things to do or not. Like, do I have a full fuel tank? Do I only use min fuel on one tank only to mitigate a large source of combustible in case of fire? Did you/How did you verify your thermocouples were accurate ad functional before engine start? Did you/How did you verify your pressure sensors were accurate and functional?

Some of you may think I am overthinking this and that is fine. However, this the way I want to approach my "flight test". Thanks.
 
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I am still interested in other things to do or not. Like, do I have a full fuel tank? Do I only use min fuel on one tank only to mitigate a large source of combustible in case of fire? Did you/How did you verify your thermocouples were accurate ad functional before engine start? Did you/How did you verify your pressure sensors were accurate and functional?

Spoken like an engineer, or a test pilot:rolleyes:

Or maybe both:D
 
Did you/How did you verify your thermocouples were accurate ad functional before engine start? Did you/How did you verify your pressure sensors were accurate and functional?

I put a heater below the engine both to warm things and to see the thermocouple readings change. The only pressure sensor I was concerned about was oil pressure so I ran an external gauge from the manifold. Turned out the oil pressure sensor supplied with the EMS was the wrong scale so a manual gauge was nice to have as the EMS shot through 140psi.
 
The only pressure sensor I was concerned about was oil pressure so I ran an external gauge from the manifold. Turned out the oil pressure sensor supplied with the EMS was the wrong scale so a manual gauge was nice to have as the EMS shot through 140psi.

that is the one I was worried about. Did you "T" off and use a pressure sensor from a car store?
 
If your engine has been in storage for a long time during the build and your concerned about the lack of lubrication on the cam, the cylinder walls and oil pump prime, how about this.......

1.Buy about 5-6 cases of oil
2.Get the airplane and engine complete and ready to run
3.Over fill the engine with oil until its completely full inside ( above the level of the cam )
4.Very gently rock the prop back and forth a couple of inches for a minute or two
5.Drain the excess oil down to the normal level
6.Start the engine

You can ask or suggest all kinds wacky questions or additions to this, but the bottom line here is that you have complete lubrication for that first start.


Over and Out
 
that is the one I was worried about. Did you "T" off and use a pressure sensor from a car store?

I used this kit for measuring oil pressure. It's probably overkill but the price for all the parts from a car store was going to be about the same ($57 with free shipping and no tax). It works great and the hose is the perfect length to reach into the cockpit.

http://www.amazon.com/gp/product/B000R5G0DO/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1

I tapped into the unused port on the oil and fuel pressure manifold that comes in one of the kits (I think firewall forward). It has 3 ports each for 3 different sensors. This isn't mine. I think I stole Vlad's picture.

DSC_0001.jpg
 
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Lots of discussions about the engine which are good.

I am still interested in other things to do or not. Like, do I have a full fuel tank? Do I only use min fuel on one tank only to mitigate a large source of combustible in case of fire? Did you/How did you verify your thermocouples were accurate ad functional before engine start? Did you/How did you verify your pressure sensors were accurate and functional?

Some of you may think I am overthinking this and that is fine. However, this the way I want to approach my "flight test". Thanks.


I did a lot of testing while building. Heat gun or propane torch to thermocouples right before installation. Yes you need power to engine monitor to do this.

Pressure transducers were tested before installation on a bench setup. I used compressed air adapter to transducer. That can also be done on the aircraft by disconnecting a hose and using an adapter hose to the air compressor hose. Works for high pressure stuff but would need to regulate down to near nothing for a carb fuel pressure.

Daily test of temperatures is to verify that all temperatures are about the same on the cold engine and are close to what ATIS is reporting.
 
Lots of discussions about the engine which are good.

I am still interested in other things to do or not. Like, do I have a full fuel tank? Do I only use min fuel on one tank only to mitigate a large source of combustible in case of fire? Did you/How did you verify your thermocouples were accurate ad functional before engine start? Did you/How did you verify your pressure sensors were accurate and functional?

Some of you may think I am overthinking this and that is fine. However, this the way I want to approach my "flight test". Thanks.
Those are good questions.

I did my first engine start and flight with half tanks.

I wanted enough in each tank so that if there was a problem, I could switch tanks and know there is fuel in there. (If you have an air leak, you may not draw from one tank.) However, on the first fight, I did not plan on switching tanks in the air.

Don't forget to drag your brakes before the first flight to break them in. It would stink to need them on your first landing and they not be ready. (I did this during one of my engine run in's. Taxied a ways with the brakes on. When the first CHT hit 350, I shut it down and let everything cool. Then I started up and taxied back, again dragging the brakes. That was enough.

Good luck!
 
Tested all my thermocouples and my pressure sensors this weekend.

I am glad I did that. Turns out my fuel pressure gauge was showing the wrong pressure, 40 psi static. I spent the majority of sunday trying to figure out what the deal was.

Turns out the pressure sensor I am using did not have a specific diagram. It just said red = 12volts. Well the new document on the website now states that it is not 12Volts :rolleyes: I will mess around with it next weekend to see if swapping the power source fixes the problem.

I feel better now that I have compared the sensors to known quantities and they had the correct reading (except fuel pressure).
 
I got a surprise on my first start. I had primed the oil system weeks before with the plugs out. I started cranking with the boost pump off and waiting for oil pressure to come up and it started up! I had forgotten to pull the mixture to idle cut off and the mechanical pump primed itself! By the time I shut it down, the oil pressure had come up.
 
Oil

If your engine has been in storage for a long time during the build and your concerned about the lack of lubrication on the cam, the cylinder walls and oil pump prime, how about this.......

1.Buy about 5-6 cases of oil
2.Get the airplane and engine complete and ready to run
3.Over fill the engine with oil until its completely full inside ( above the level of the cam )
4.Very gently rock the prop back and forth a couple of inches for a minute or two
5.Drain the excess oil down to the normal level
6.Start the engine

You can ask or suggest all kinds wacky questions or additions to this, but the bottom line here is that you have complete lubrication for that first start.


Over and Out

With the engine installed on the airplane there is no way overfilling will allow the oil to reach the cam. This could be done on a rotating engine stand.
 
Great and timely thread for me...but....

I have a firewall mounted oil cooler with the ports horizontal. I can't see any way to fill it and keep it filled prior to engine start. I could unmount it, fill it, and try to get in place?

Start the engine with the cooler in a different orientation? eeek.

I'm just thinking that air will collect in the oil cooler. Or will the viscosity of the oil versus the oil just push it though ahead of the oil?

Either way, the engine gets a gulp of air, right? But it's under pressure, so the effective volume will be 1/4 of normal...thinking out loud.

I do plan on gravity filling all the lines ahead (to both sides of the pump).

IDeas? Corrections to my thoughts?

orientation, looking at the firewall:
-------------
o o
________
 
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