Kitfox 7 Apex Build Episode 62 Apex Engine Tear Down

[@cramersclassics]

Great job Brian! We just flew my friends Gary's Apex Kitfox 5. The wave of the future.....

[@oldjarhead386]

Me personally, I treat snowmobile repairs of all kind as if they were A/C engine. My reasoning is that I don’t need to be out in the middle of the UP after dark when it’s -15 or worse with a failure. An engine failure especially because it’s light and maybe a little heat. It’s not a dead stick situation but still a potentially dangerous situation. Btw, I used to build, tune and race my own built turbo and supercharged cars. I retired from that and got into sleds. 2 Rages, 1 Rx1, an Apex and a few two-smokes. I guy decent units and completely restore them. I also have a little aviation experience as a flight engineer in the Marines. Thanks for the videos.

[@916medic]

Dam Bryan I learn so much from you. I know you don't know but you have definitely influenced my life. It's because of you I got into kitfoxes and building my own. My dream is to fly my 2 boys around the sierras. My 6 year old wants me to buy a kitfox so we can go flying. Its awsome. I feel like I owe you big time. Thanks for the videos. Keep up the good work.

[@blancolirio]

Great explanations Bryan!

[@johnnix4094]

Head gaskets blow when engines overheat. Be sure you check your radiator for obstruction or the same thing could happen to your new engine. I am surprised your temp gauge didn't register an overheating condition but gaskets blow where the engine is the hottest and you would expect it to be the hottest in the middle if coolant is restricted.

[@BowenAero]

The entire coolant system was flushed and the radiator was pressure tested before running the new engine. 40 hours on the new engine now and running perfect.

[@martykath4427]

Not all coolant are compatible with motorcycle engines. Our local radiator repairer found he was having repeated water pump seal failures on a dirt bike until he found a BP product that worked well. From memory it may have been abrasion from silicone??

[@HeeHawHighlander]

Great stuff Bryan! My spare Apex core is at Casey’s getting the full meal deal overhaul and vapor hone treatment. I’m sticking with stock as it has plenty of power for Western PA flying. Pretty excited to soon have a zero timed shiny engine sitting on the stand in the event my flyer even hiccups. 82 flight hours on top of the 7500 sled miles it already had and she’s running flawlessly.❤️ Keep up the great work

[@oldjarhead386]

Old hot rod lesson. Don’t let bad engines sit.

[@44hawk28]

I've been playing with engines for a long long time. Blue Devil is an excellent mechanism for plugging small coolant leaks and the like however you cannot over apply it. You have to know exactly how much coolant your engine and cooling system uses figure out how much they recommend, and then try about half that amount or less. And that's for an automotive use where you can pull off the roadway. I've never used an entire amount of coolant additive except for when I add water pump lube. Water pump Lube or coolant additive that allows the engine to run cooler. Surprisingly that head and cylinder do not look that bad. Clean them up, spray them well with some Gibbs but it looked like they cleaned up quite well run a Fred Chaser through that spark plug hole. To tell you the truth I would have checked very carefully running an aluminum head with spark plugs that didn't clearly have anti-seize on them or had replaced the threads with inserts. But that might have actually aggravated this particular situation. There is a company called banks that makes a coolant that uses no water in the cooling system and it keeps the problem with the coolant expansion to a bare minimum. Because it has no actual water in it, or at least the tiniest amount. It does not cause the issues that a water mix antifreeze does. I believe it can actually handle over 300° of temperature without noticeable expansion or somewhere close to that temperature.

[@71volare]

For aviation use this engine should be scrapped.

[@peterhancox5268]

Another interesting video Brian, thanks

[@thompsonjerry3412]

What would be cool for your back country plane is a turbo normalizer. I would use a supercharger and a constant speed prop for high altitude

[@ginacalabrese3869]

Edge Performance makes this engine with a turbocharger that puts out 300+ horsepower. It's what powers Steve Henry's plane that he wins all the STOL competitions with.

[@sneakybow1]

@@ginacalabrese3869 and it's about $45k for that Edge Epex 300ti

[@kingersgarage]

You’re spot on with your boost logic. I have been boosting for years. I did a twincharged build. With a turbo feeding the supercharger. The apex engine loves boost and is very robust. Love your EM solution.

[@General-Grant]

When I had a honda based conversion on my Midget Mustang (N517G), I ran a straight waterless coolant - worked great and had a high boil point. Jegs part numbers 370-EC10064 (NPG RACING COOLANT .5-GAL) and 370-EC42064 (EVANS PREP FLUID .5-GAL).

[@LTVoyager]

The only issue that may come up with the Evans coolant (which is basically just 100% antifreeze with no water) is that the heat transfer capability of the fluid is a fair bit less than water or even the normal 50/50 mix. So, overheating may occur in high sustained power applications like aircraft unless the radiator is upsized.

[@mercedescherokee6853]

Which Honda engine are you running?

[@raydreamer7566]

Great video - I really enjoyed the approach , teardown and the advice warning for coolant leak additives as well as the choice for HP power levels .....

[@johnp9773]

Great channel. I’m surprised you even talked to that guy

[@bjrnvaa6471]

These engines are bullet proof stock up to 300 HP. If modded internal ARP , carrillo, cometic gasket ,valve springs, CP pistons, cames, cryo treated crank, mode oil pump for mere flow, you can have a reliable 450hp turbo engine.

[@bjrnvaa6471]

You altso need bigger coolant reservoir

[@mikercflyer7383]

I do not know anything about engines but I found real interesting

[@jeremykemp3782]

Great information again, thanks Bryan

[@michaelmartin2486]

If you let a engine just sit after blowing a head gasket and leaking coolant, the cylinder will corrode. Always drain fluids and get the head off asap.

[@BowenAero]

Things I get to learn the hard way.

[@paulkainer269]

one thing to ponder. both a turbo and supercharger will increase the engine volumetric efficiency. the disadvantage a naturally asperated engine has is the faster the engine speed the more rapid the air and fuel have to enter the engine through all the valve train passageways and air filter. mechanical boost helps compensate for the resistance of all that effect. engine manufacturers made changes like increase valve surface area, number of valves etc. some work in early chrysler 300 series cars made a red ram was a tuned inake to have a boost because of long intake runners. they were tuned for the desired engine hp and torque curve. But as for a plane. the weight of a super vs the weight of a turbo is a big deal. Once you have your engine turbo and fuel system upgrade you might find you can load the prop more aggressively and burn a little leaner on throttle back positions in cruse. if your not happy with the turbo engine it will not be hard to get rid of the package on line. and of course i enjoyed the video!

[@Carbibbles]

10:1 compression is a bit high unless you plan to run 100+ octane fuel. For an application that requires more safety margin like this, 8.0:1 to 8.5:1 would probably be a lot better. Detonation will take out an engine really quick and the line between optimal combustion and detonation gets thinner and thinner the higher you go with compression. Lower compression with a few more pounds of boost will give you the same power output but give you a more forgiving engine. What engine management are you running?

[@BowenAero]

Stock compression is 11.5:1, we are also using a closed loop system that can pull timing.

[@Carbibbles]

@@BowenAero normally I wouldn't interject because I don't want to come off rude, I enjoy your videos and I hope to build a kitfox someday. I really would recommend against higher compression like 10:1, I'm not sure if you are running mogas or high octane though? I do engine calibration for a living so I do have some experience on the topic. If you look at factory turbo engines most of them are in the 8s for compression, only the more modern direct injection turbo engines have started running closer to 10:1. I've tuned some of these and they typically have to run extremely low ignition timing to keep from getting knock, and they have very sophisticated knock control in their ecus (much better than most aftermarket ecus). You don't really give up much by dropping the compression down, the biggest difference will be a bit less torque response but I don't think that would be a concern for your application. Anyhow, figured I would drop my $0.02, I look forward to watching some videos of you adding a turbo if you decide to go that route!

[@justme-n-gracie]

I used that Blue Devil garbage when it first came to our local NAPA 16 years or so ago... it completely clogged the radiator, heater core and block of the Ford Explorer 4.0 that I was trying to limp through winter to rebuild in Spring. I ended up calling it a total loss and scrapped the vehicle. The product was used exactly as directed. I did get a refund for the chemical product but had quite a loss on the vehicle. Lesson learned. Never again.

[@ronmac1832]

I've wondered about the durability of a bulletproof Japanese engine running constant high rpm. Sorry to hear about the failure!

[@sneakybow1]

8k rpm is nothing for these engines. That wasn't the cause of this. These things get ran higher rpms than this all the time in snowmobiles. That coolant "fix" did this. 8k on the motor with a 3.83 gear reduction on the gear box means this thing isn't straining at all at that rpm range.

[@charleskuss8538]

Thanks for the education. That said, I was hoping to watch you completely tear down the engine. The only "cure in a bottle" I've ever found to work is Chevron Techron fuel injector cleaner. That is not an absolute cure. Often, fuel injectors need to be sent out to be tested and ultrasonic cleaned.

[@andremarais2706]

Coolant gel is the result of not draining and flushing on regular basis. Household bleach disolves gel and then a vinegar wash with plenty water after.

[@christophergeorge6581]

By way forgot to mention the apes gins on 2011 up to 2018 th HP was increase to 165 HP the heads I believe went from 3 valves to 4, the reason I know my 2p13 a Ex was faster than 2006 also they made so e other changes ges compression was higher and on 21o13 specified use of premium fuel were 2pp6 used regular. Christopher Ottawa Canada

[@Mike-01234]

Turbocharging is the best way to go IMO there is lot more support for that with that said also more complex then a supercharger more things to go wrong supercharger just a belt and you can change the pulleys doesn't use engine oil usually they have their own oil. I'm assuming the supercharger is like a paxton something. If it's made for a sled a screw, or roots type supercharger would be better for low end power where aviation you don't care about power right off idle. Aviation engines generally just use a paxton type supercharter. Probably where Paxton got the idea from aviation engines such as the Rolls Royce Merlin, or P&W radials.

[@MaxRunia]

Even for everyday flying a turbo would be nice for maintaining power at altitude. But having 300ish hp on a kitfox would be sick

[@CameronRamsey-fu4di]

what kind of longevity are you expecting with the higher RPM Apex engine?

[@larryw5429]

Jesus how long did the motor sit with that water in it to rust it eshhh!

[@BowenAero]

About 8 months.

[@leeross7896]

Cant find this answer anywhere, What are you guys expecting TBO to be on these yammi's? Whats the TBO on the Gearbox?

[@BowenAero]

Unknown really. That's why we are collaborating as a group and compare oil samples and experiences. We have hopes, but flight time will tell the tale. I am at 250 hours going strong.

[@GrantOakes]

Great information!

[@DBR9009]

Hello! Hope all is well. What are the dimensions of your hangar?

[@KeithPatterson369D]

Great video as usual buddy!

[@timhuckabay]

Darn! When did this happen? Did the engine quit while flying? You mentioned you have other engines. Are you going to be able to drop another engine in and get back in the air asap? I’m looking forward to another adventure with your race engine build

[@BowenAero]

You can click the video tag link at the beginning to go to the episode about swapping out the engine. It was about a year ago. This engine never quit, just leaked coolant.

[@daisybeagle6259]

Did I miss the removal of the stuck spark plug?

[@BowenAero]

I let it soak in some triflo and was able to get it out, but it will need to have the threads cleaned up.

[@gordb4343]

Are you going to turbo this

[@BowenAero]

I have weighed the positives and negatives and really don't see the need for the turbo and the added complexity, weight, heat, higher fuel burn and engine wear. If I was building an all out competition plane than I would, but for my current mission the 160hp is so awesome already, I don't find that I am in need of additional power.

[@doncatch1]

Good stuff.

[@flyingmaniac3827]

also weld the crank,re-balance and grind,as it will experience more force.

[@wadestoelting5942]

I was thinking the supercharger options are driven off the same side as the SkyTrax PSRU, so not a good option for the application, true?

[@BowenAero]

Actually they are driven off a PTO added to the other end through the Stator cover.

[@stephengloor8451]

You need a good ECU as well. A Haltech or SDS will do the trick

[@BowenAero]

We use AEM ECU’s

[@markstoll9636]

really good content...thoroughly enjoyed the learning process. i would have particularly like to have heard your thoughts on why you added an additive to the coolant. what were your reasons? Did you have any prior clue that the gumming up may occur? thx

[@BowenAero]

I explain it in this video kzbin.info/www/bejne/qoSYmGdro66Ljtk

[@albatross9873]

Serious issue in a plane. Coolant was junk. Why did you use the blue devil additive to begin with? Was there a leak before the head gasket totally let go? Cleaned up well enough. Good luck :)

[@BowenAero]

There was a radiator leak

[@larrryp]

I love your video's I'd like to know more about Casey your engine builder? Ive got an 2006 Apex GT and am looking into rebuilding it? Could you give me a link or phone # Thanks Larry

[@BowenAero]

Casey Hauck [phone]

[@kevinbisig3261]

The issue with the spark plug is typical with the different metals and coolant in the combustion chamber. The threads on the head are likely fused to the spark plug. Once the spark plug is stuck, getting it removed has a tendency to destroy the threads in the head. If that happens you could use a heli-coil. Not sure how advisable this is on an aircraft engine. I have used Tap Magic to help lubricate during a plug removal, but only as a last resort, when heat and or Aero Kroil didn’t work. If using tap magic, be sure not to apply heat until all tap magic has been solvent removed. The bigger issue is to understand why the failure occurred (though I’m sure you are aware of that). Keep us posted on the diagnosis of the failure. My Kitfox is scheduled to arrive in November and the apex was an engine I was considering. Also, not sure about the regulations but spark plug thread lube does help if it is applied at plug installation.

[@ginacalabrese3869]

Not sure what happened to my original comment but I was saying Water/methanol injection significantly reduces the inlet air temperature of boosted engines. Developing a system for the Apex would be cool. I don't even think Edge has it for their Epex.

[@BowenAero]

We are looking at that option with real potential.

[@mnice59]

WEP (war emergency power). P47 the best fighter of WWI

[@General-Grant]

For spark plug, let it soak for a couple days w/penetrating oil.

[@BowenAero]

Done, it worked

[@desertfox3860]

That looked pretty scary in there when you pulled the head off! I agree, airplane engines shouldn't work"most " of the time! They should work "all" of the time!

[@BowenAero]

As stated above, I should have pulled the head right away and none of that corrosion would have happened.

[@ryandavis4457]

Be a good build series.

[@nemackfire]

Just confirms that it should stay on a snowmobile! I am really not seeing the advantage of building a really nice airplane and putting on a engine the needs an overhaul under 100 hours. High RPM's for hours and hours makes me nervous!

[@BowenAero]

When you build your airplane you can put an underpowered expensive Rotax on it and see if you have any better luck. I choose this engine for a reason and I’m very happy with it and the amazing performance.

[@craigsanders6925]

Doesn't sound like the engine was the issue but the additive to the cooling system that caused the problem. I had a Yamaha R1 track bike which is essentially the same engine. It had over 24K on it of mostly track miles when I sold it. Valves didn't need any adjustment at 20K. These are robust engines and running it 8K+ for hours on end didn't seem to have any ill effects on it.

[@nemackfire]

@@BowenAero I am not a Rotax person either. Each to their own, really enjoyed your build and hope you have many years of enjoyment with it!

[@feloniousmonk3049]

@@craigsanders6925 The constant load on the engine and the prop and wind resistance /drag is completely different from that of a racing motorcycle. You're off the throttle for most every turn.

[@craigsanders6925]

@@feloniousmonk3049 That's true, but since this was a track bike many of those miles were at max or near max RPM. These engines are robust.

[@GalaxyRepairs]

Engine looks like Yamaha VX110 modified.

[@Captndarty]

I’m not sure if Yamaha will sell you a brand new motor but if I was building an airplane worth 100 to 150K or more I definitely would’ve bought from the beginning a brand new motor from whatever source I chose.

[@BowenAero]

You should do that with your project then.

[@Captndarty]

@@BowenAero I did and it’s called a Rotax 915👍🏻

[@craigsanders6925]

I'd trust an engine built by the guy that built my road race motors more than a factory engine. I'm sure his attention to detail is better than factory. Having road raced motorcycles for many years I know several builders I'd trust to build it. It's also much cheaper to build with better parts if you choose to put in better rods etc....

[@Captndarty]

@@craigsanders6925 but he didn’t go that route first so there’s that. Now he’s into 2 engines and all the time waisted in the process. Time is certainly worth something. I’d trust any factory engine over one touched by any shop even a race one. Humans error and the more automated the less chances of that error.

[@craigsanders6925]

@@Captndarty Why was it time wasted, h'e's learning about the engines and how they are put together. I'll bet he doesn't have half the cost of your 915 in them. I've seen how meticulous the guy that built my motors was when putting them together. Everything weighed and balanced. You don't get than on a factory motor. I'm sure his tolerances were tighter than the factory too. A little head work to get better flow and my engines made 20% more Hp than factory and were extremely reliable. I'd have them rebuilt after two years of racing. Probably could have gone longer without failure. That was a motor with a 16K redline.

[@thepostapocalypticgardener9435]

No need for special tools for overhaul

[@GrantOakes]

WOW, looks like Blue Devil just bought themselves a LOT of negative publicity!

[@cohocarl]

Looks like that head gasket had been leaking for a while.

[@BowenAero]

Hard to say. The corrosion was from letting it sit for 8 months after I pulled it.

[@kamikadze242]

Apex with stock engine 250hp 10years of driving and trying to kill it, no luck😉 its bulletproff.

[@flytoday]

turbo on an engine that's already been cooked is inviting trouble into your life

[@ChimenyDust]

Yup. Buy a k series and put a turbo and you’ll be good for life.

[@BowenAero]

Cooked? If there is no head warp or if it is resurfaced and new internals, I disagree.

[@jonathanhuman7333]

Can you take legal action against the additive company? Someone could get killed if they keep selling that crap.

[@flytoday]

Apex cores are cheap but getting old and neglected