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Geowitz
10-12-2011, 09:39 AM
So I went to see an actual HKS 700T down at Greensky Adventures in Florida. It's a pretty engine and I am very optimistic about the install. It will definitely work one way or another. Placed an order and it should be here in a few weeks. Here are a few pics with my cowling. It's the Classic IV smooth cowling so there is a little more room, but the round cowl should be adaptable as well with a few modifications.

A few pics below. I will keep updates on this thread with pertinent info about weight and balance, fitting of components, engine mount, etc. Preliminary thoughts on these issues looks promising.

Mnflyer
10-12-2011, 10:02 AM
You'll like the HKS its a great engine, you'll have no problems with your cowl. I have a round cowl and had to make a couple of extra bumps but its worked good for 460+ hrs.

Geowitz
11-16-2011, 05:39 PM
:D It's here!!!!!! Came with wiring harness, exhaust, fuel pump, fuel filter, air filter, intercooler, etc...

Gotta start getting things ready to make an engine mount. Hope to have it at least bolted up in a few weeks.

Dorsal
11-17-2011, 04:55 AM
In the words of Tim Alan "argh argh argh", very nice:)

kmach
11-17-2011, 07:43 PM
Hi ,
Nice looking engine.
I know little of this engine so please forgive any stupid questions. From looking at the pictures, is this a 2 cylinder ? what kind of horse power ?

Geowitz
11-17-2011, 08:47 PM
Yup, 2 cylinder turbo, 80HP, BUT just to clarify(and brag a little)it's a true(takeoff to 3 min max) 80HP from Sea level up to 16,500 feet(Max continuous is 79HP). Because of the turbo it out performs the Rotax 912UL from the ground up and actually surpasses the 912 ULS in HP from 7000 feet and up. Granted, the Turbo version is somewhat new, but their track record as a company overall is excellent and the reviews on the engine have been consistently great. Don't get me wrong. I like the Rotax 912's and wouldn't mind having one, but HKS is also a great, reliable, and proven company.

The 60 HP version is the same size externally, but the new turbo version is actually a longer stroke with different oiling and other internal changes. The engine has two separate ECMs each with their own injectors, ignitions, and sensors. I've got a 72 inch IVO Medium Prop with in flight adjust for it which is pretty necessary to take advantage of the consistent power at all altitudes/air densities. Total weight should be around 155 lbs with everything including prop. The power and weight fit the Kitfox IV perfectly.

I've got the smooth cowling so I'm gonna try to fit the intercooler inside, but it would easily mount where most currently mount their radiator. Since it has the same external dimensions as the 60HP it will fit in the round cowl without too much modification besides trimming in a few small spots for clearance.

Geowitz
11-25-2011, 10:04 PM
Progress on the mount. I tacked it up with a mig and ER70S-6 wire. Will do the final welding with gas and same rod.

Geowitz
11-30-2011, 12:24 PM
My jig worked and the mount actually lines everything up perfectly :D. Now, just need to figure out where everything can fit. Biggest hurdle is the inter cooler.

rawheels
12-01-2011, 05:14 PM
Geo,

How did you figure out the material sizes and layout of your mount? I am supposed to go pick up a 700e on Sunday for my Model IV. I've been looking at Jerry's design down at Green Sky, but I don't like how the prop doesn't extend near the center of the cowl. Trying to figure out the design and loads for a new mount design seems very hard.

Are you using a Kitfox produced smooth cowl? If the cowl opening lines up with your prop, then the prop would be close to the center of the round cowl as well. Hmm...Do you think there is any room to fit a muffler behind the engine on your design?

Ryan

Geowitz
12-01-2011, 06:17 PM
Geo,

How did you figure out the material sizes and layout of your mount?

I had a friend who is an aeronautical engineer do some load calculations for the engine weight and max G forces that could be experienced which is about 6 positive g's. With plenty of safety margin I used 5/8 inch .049 for the two bottom tubes, and 1/2 inch .049 everywhere else. The actual layout of the tubes was really determined by the five points on the firewall and the engine mounting plate. I had no choice but to to go from point A to point B while working around the exhaust pipes and while triangulating everything. You just go where you can. If you're worried you can gusset everything too. There are a few short tubes I added after these pics that really tie everything together and add more triangulation.


I am supposed to go pick up a 700e on Sunday for my Model IV.

Congrats! It's a great engine.


I've been looking at Jerry's design down at Green Sky, but I don't like how the prop doesn't extend near the center of the cowl. Trying to figure out the design and loads for a new mount design seems very hard.

Really, if you follow the typical examples out there you're not gonna have a problem. They're all over designed anyways. However, it's nice when all the work has already been done and proven. It's hard to fit the engine and muffler in any of the cowlings because of the height of the two added together. You definitely want the muffler below. The problem is not that the engine or muffler is any bigger than a Rotax. It's that the HKS uses a bed mount which takes up space below the engine. This then pushes the prop up a bit with the gearbox in the up position. You can also put the gearbox in the down position like MNFlyer - http://www.teamkitfox.com/Forums/album.php?albumid=18 . He has pics in his profile that give a good overall design. All designs are gonna require some work to modify and fit though.


Are you using a Kitfox produced smooth cowl? If the cowl opening lines up with your prop, then the prop would be close to the center of the round cowl as well.

Yes. It's the official Kitfox smooth cowl. The thrust line is basically the same for both cowls.


Hmm...Do you think there is any room to fit a muffler behind the engine on your design?

Ryan

Sorry, but probably not. The nice thing about the Turbo is there is no need for a muffler so I could arrange the tubes on the bottom a lot easier.

Geowitz
12-01-2011, 08:56 PM
I like your motor mount a lot more than I do mine. Want to make another?
:)

BTW, where are you going to mount the oil cooler and oil tank? Will you use the HKS tank or make one of your own to fit?

Fitting the muffler would be your biggest problem. I suppose if you got rid of the big canister muffler and went to a smaller muffler you could pipe it parallel to one side of the two lower supports down to the lower center allowing you to use this design. Probably stick out of the bottom a little near the back. If you put the muffler parallel to the firewall it would have to stick out of the bottom of the cowl a little too.

The oil tank will be stock HKS and go on the right side of the engine just below the tubes. With the engine lowered to the correct thrust line though this forces the oil tank lower which could get in the way of the muffler depending on how it is arranged.

Oil cooler will have to go below the engine and some slight cowling modification will be required. Inter cooler fits and will hopefully work in the back on top with ducting. Otherwise it would easily go where the Rotax radiator usually goes.

rawheels
01-03-2012, 12:21 PM
Geowitz,

Any new updates on your project?

Geowitz
01-05-2012, 08:33 PM
Holidays have slowed things down. Mostly just thinking how to work things out and trying to mock up different scenarios.

Latest thoughts and changes...

1 - To fit the oil tank on the passenger side I had to make the foot well shallower by 1 inch moving the tank closer to the firewall so as not to interfere with the right side fuel injector(don't have brakes on the passenger side anyways). This also allowed me place the tank high enough to put the cooler up front, but not too high. It's still technically out of spec for drain back issues, but I'll just have to hand prop it before each start up to make sure there's no hydraulic lock like everyone else. This also required eliminating the right side tube brace, but I reinforced the area with a .050 inch plate gusset. Not a big deal.

2 - Oil cooler fits fine up front since I moved the cowling 2 inches forward. I had to do this so the IVOPROP and spinner setup would fit correctly to the cowling. Took some pain in the butt fiberglass work, but worth it for the spinner fit and extra room.

3 - Placing the inter cooler on top works as far as space availability, but makes ducting very complex. I'm concerned about the hot air contaminating the rest of the engine compartment so the inlet and outlet sides would have to be ducted. That's too much for me to want to mess with so I'm probably gonna put it underneath the engine and do some fiberglass work on the bottom of the cowling to create its own simpler inlet and exhaust. Worst case scenario, I put it where the Rotax's have the radiator.

Geowitz
03-13-2012, 05:19 PM
Making some progress. Just had a baby girl so things are crazy, but still managing to put in a few hours a week.

I have the oil cooler mocked up and satisfactorily placed. I will replace the adele clamps by the exhaust pipe with a welded on tab and the aluminum angle will be trimmed to save some weight. I had to extend the cowling by about 2.5 inches so the UHS spinner and the IVO prop would line up with the cowling. That was a pain, but worth it for the looks. The ignition coils, map sensors, boost control valve, and regulator fit nicely above the engine on the firewall with aluminum angle brackets. I had to remove the right side brace and replace it with a gusset so the oil tank would fit better. Tank mounts easily with adele clamps with supplied brackets. I will be adding 2 more braces at the adjoining joints to stiffen up the mount. They are probably overkill, but better safe than sorry. Engine monitor wires and other electrical stuff will go through the firewall on the sides without any problems. Last thing to mount and figure out is the intercooler which will go under the engine with modifications to the lower cowling to make a scoop.

DesertFox4
03-13-2012, 11:13 PM
Just had a baby girl so things are crazyFirst off Geowitz, mega congrats on the new family members arrival. We hope mom and daughter are doing very well. A future co-pilot maybe?

Nice progress on the firewall forward.
Lots of hours in those cowlings no doubt.

Hope you can still find a little time now and then to work on your Kitfox. We know Papa duties take priority. Congrats again on your little girl. Enjoy every minute with her.

inzersv
03-14-2012, 09:28 AM
Geowitz, congratulation on that baby girl. The spice of life. Oh, and your firewall forward is looking great.

Geowitz
03-14-2012, 07:26 PM
Thanks guys! Everyone is healthy and doing well. Luckily I have a VERY understanding wife who is looking forward to the Kitfox getting done so while daddy duty comes first, we won't let this project fall by the wayside.

Geowitz
04-29-2012, 06:56 PM
Making a lot of progress. Most is not really noticeable as it's a lot of small details with various mounting issues and wiring, but I'm getting closer. Here is a few pics of the finished mount and firewall. Hopefully motor will bolt on permanently next weekend.

DesertFox4
04-29-2012, 10:06 PM
Back at it Geowitz. With the new baby sleep is probably at a premium right now. Keep after it. Progress is sometimes hard to measure at points in a build but you are progressing. Wiring, not my favorite thing.

Geowitz
05-04-2012, 04:41 PM
Perhaps the last time I have to muscle the engine into place?

Going together well. Finally working on the intercooler mounting. Will update with pics soon.

Geowitz
05-09-2012, 08:41 PM
Intercooler mounted with air box supplied by air scoop. The front mates up to the cowling and will have a gasket. Air will exit out the bottom of the cowling ahead and separate from everything else to prevent heat contamination. I had to drop the front bottom half of the cowling about 1.5 inches to clear the intercooler. Still have to do some shaping and sanding on the fiberglass, but the profile fits in relatively well. In other words, it doesn't really look too much like I retrofitted it.

Geowitz
05-18-2012, 09:43 PM
Cowling is now getting close to paint. The one issue I had was that the intercooler was just barely too wide to fit. I could have cut and dropped the cowling down more, but I think it would have looked too big/wide and funny so I just made cutouts for the fittings. This area of the cowling will be painted black and the fittings are black so they will blend in well. Also trial fitted the prop and spinner to see how my cowling lined up. Almost perfect. Will have to do a little blending to get a smoother transition, but overall I'm pleased.

Geowitz
06-12-2012, 05:22 AM
Just an official update.

Got the throttle linkage figured out. Also have the intercooler piping done along with oil lines and fuel etc so basically all of the plumbing is done. Wiring is all that's really left except for some painting here and there.

Mnflyer
06-12-2012, 10:05 AM
Looking really good am waiting for your first run and flt. Keep up the great work.

WWhunter
06-13-2012, 05:48 AM
Gary,
Flew over your place the weekend of the Fly-in in Alex. Looked like you were tending to the garden. I was in one of my other planes so didn't land. The winds were strong and it was a VERY bumpy day.

I sent someone your info that was interested in the HKS but doubt he followed through.

I really like that HKS....... Geowitz....plane is looking good!!!

Av8r3400
06-13-2012, 06:09 AM
Will that install require baffling?

Geowitz
06-13-2012, 06:29 AM
Thanks for the comments.

I'm still tossing the "targeted cooling" ideas around in my head. Apparently some installs need it, some don't, but if I were to need it the design would be more like a deflection plate wrapped around the back of the cylinder or a manifold over top the cylinder with an inlet in front. My first run will be with cowling off so I'll be watching the temps closely, but I think worst case scenario will be making some manifold boxes pointing forward.

Geowitz
07-18-2012, 05:19 AM
CLEAR PROP :D

http://www.youtube.com/watch?v=u8kVJg53Gxc

Started the engine last night. Took a little cranking to get fuel through the injectors, but it started without any problems. No leaks and temps look good so far at least with the cowling off.

A little wobble/oscillation or vibration of sorts in the Ivoprop visible at the tip of the in flight adjust motor. Looks like the tip of the electric motor is tracking slightly off axis. I checked the blade tracking and all blades are within 3/16" and I'm assuming at this point that they are balanced. Didn't go over 3000 rpms so I don't know if it would even out. I'm suspect of my mounting bolts being unevenly torqued with the fiberglass spinner backplate causing the motor to not be bolted on straight? The hub looks like it's spinning fine without much movement, but the tip of the IFA motor looks like it's wobbling, not loose, just out or round/off axis. Any ideas?

rwaltman
07-18-2012, 05:39 AM
Sorry, cannot help with your question, just wanted to say congratulations!

Woodennickle
07-18-2012, 07:18 PM
Not an expert, and haven't stayed at a Holiday Inn lately, but I would say that 3/16" is too much. :o

Av8r3400
07-18-2012, 07:58 PM
Not for an IVO. They flex quite a bit.

Mnflyer
07-19-2012, 09:46 AM
Agree not for an IVO in fact IVO says not to worry about tracking or at least they did a few yrs back.

Geowitz
07-19-2012, 08:20 PM
I think I may have found the culprit and I'll be an idiot if it's what is causing the problem. At this point though I'd rather be an idiot and this fix work than it be something serious. I'll report back tomorrow after another run up to check.

Thanks for the comments. I'm so close now!

Geowitz
07-22-2012, 05:30 PM
Well, I may be an idiot, but my thoughts were incorrect and I have not fixed my issue yet. I have noticed though that on subsequent starts everything is rather violent and shakey until the prop gets up to speed. I mean bucking bronco type engine violence. Is the moment of inertia of the medium IVO too much for the 700T? I'm starting to lean this way which is unfortunate because I had high hopes of the IFA taking full advantage of the turbo. Might have to give that up for a lighter prop. Idle should be around 1600 rpms. At this speed the prop will go back into bucking mode with violence. Around 2000 rpm is somewhat bearable, but my panel is shaking like it's doing the jig. Above 2000 I can almost feel numbness in my body from the vibrations and see the panel shaking. It smooths out relatively above 3000 rpms and gets better the higher I go. Got it to 4300 rpm today.

Any thoughts? If I had a prop with too much MOI what would be the dead give away symptoms other than ripping my gear box apart after continuous use? Anyone have any clue what the MOI is for the medium IVO?

rwaltman
07-22-2012, 08:29 PM
... on subsequent starts everything is rather violent and shakey until the prop gets up to speed. I mean bucking bronco type engine violence
... Idle should be around 1600 rpms. At this speed the prop will go back into bucking mode with violence. Around 2000 rpm is somewhat bearable, but my panel is shaking like it's doing the jig. Above 2000 I can almost feel numbness in my body from the vibrations and see the panel shaking. It smooths out relatively above 3000 rpms and gets better the higher I go.
A few data points, different engines, (HKS-700e non-turbo) different propellers, (3 blade powerfin in my case).

(a) Mnflyer (http://www.teamkitfox.com/Forums/member.php?u=4) reports "I can idle mine at about 2000 for warm up and after a flight for cool down it idle very nicely at 1700. "

(b) In the few engine runs I did on my KF I observed the same and had the same concerns. (Instrument panel turning into multiple instrument panels?) The shaking was too much until ~2200rpm, it could be called "smooth" above ~2500.

Waiting to get it back from its annual (this is turning into another litle horror story, the plane is not at fault.) to start experimenting with carbs and propeller balancing.
I am beginning to wonder if that may be intrinsic to the 2 opposite cylinders design


Anyone have any clue what the MOI is for the medium IVO?
I went through that some time ago. The only reference I could find is for the ultralight, not the medium. Also, it is from a competitor, use it as an unreliable lower bound.

From http://www.powerfin.com/features.htm:
"A 72" – 3-blade Ivoprop Ultralight propeller is about 4,500 kg/cm2"

If everything else fails, there is an article here on how to measure it:
http://www.800-airwolf.com/pdffiles/ARTICLES/part31.pdf

Roberto.

Geowitz
07-23-2012, 05:11 AM
Roberto,

Thanks for your personal experience reports. I have been scouring the net for anything and had seen what you posted for the IVO light prop and how to measure it. Might try that soon actually. The 700T has a c type box that is spec'd to handle up to 6000kgcm so the hope was that with all the 912 ULS's running them(even if they were over that MOI which I suspect) that the 700T had a good chance too. While it is only 80hp it's 80hp at 2000rpm prop max(5300 engine) because of the gear reduction. This thing has no problem spinning it up and all of my high rpm runups have required the upper half of the medium blade's pitch range.

Took the prop off totally and it ran fine. Everything else seems to be in order and prop appears to be balanced. Is there anything else that can cause this kind of violence and vibration?

rwaltman
07-23-2012, 07:49 AM
...Is there anything else that can cause this kind of violence and vibration?

Wild guess: Engine rubber mounts too rigid, or torqued too tight?

Thinking of other potential sources of information, I assume you know about the HKS group in Yahoo: http://groups.yahoo.com/group/HKS-engines/

Are there any groups dedicated to airplanes where the HKS is the norm rather than the exception? (Thunder Odyssey?)

Roberto.

Mnflyer
07-23-2012, 11:11 AM
Hi Geowitz, the HKS will not run smooth at 1600 R's at all, my 700E is good around 2000 on warm up 2200 smooth as needed but below 2000 ruff, after flying and at cool down I can and do idle down to 1700 R's and its smooth will idle forever just purring away. Not to discourage with the IVO but I tried a 2 blade quick adjust on my Kitfox HKS and had no good results after 20 min of flt the CHT's were at max, I had removed the 3 blade GSC to try the IVO reinstalled the GSC and temps were no problem. After that I installed a 2 blade 68" Warp Drive and it has worked great engine idles better climb inproved as did cruise and temps stayed excellent. Incidentally I found no upside with the IVO when I tried it did not help getting into the air or climd nor cruise, I fully understand wanting the IFA capability though I do believe that with the HKS torque curve that an IFA prop would be great.
PS I noticed a big inprovement in smoothness when I removed the 3 blade GSC and installed the 2 blade Warp Drive.

Geowitz
07-23-2012, 11:31 AM
With the turbo and lower compression there should be a possibility of a lower idle though. Not that it really matters. I'd be fine with 1800 rpms or even 2000 if everything proved to be smooth enough from there on out. Before I give up on the IVO I'm gonna try it in two blade and see what happens.

I'll check my mounts again. I actually tightened them after the first start because I thought they were too loose. Thinking more about it I don't remember as much violence or vibration in the seat of my pants on the first start when the rubber mounts were more loose. Perhaps I didn't notice because I was so excited otherwise. I'll try backing off them a little to where they were before and try again.

rwaltman
07-23-2012, 12:07 PM
I'll check my mounts again. I actually tightened them after the first start because I thought they were too loose. Thinking more about it I don't remember as much violence or vibration in the seat of my pants on the first start when the rubber mounts were more loose

The installation manual for the 700E specifies the torque: "The tightening torque for the four 10mm bolts or studs is 4.8kgm. (34ft.lbs)"
(Have not read the 700T manual.)

Roberto.

Geowitz
07-23-2012, 12:51 PM
The installation manual for the 700E specifies the torque: "The tightening torque for the four 10mm bolts or studs is 4.8kgm. (34ft.lbs)"
(Have not read the 700T manual.)

Roberto.

I'm actually referring to the Barry rubber isolation mounts which are attached to an adapter/spreader plate I got from Green sky Adventures. The adapter plate bolts to the block with the specs you mention and is fine. Thanks.

Geowitz
07-23-2012, 07:59 PM
Ran the test described here on my Medium IVOPROP IFA - http://www.800-airwolf.com/pdffiles/ARTICLES/part31.pdf

At 30 oscillations I had an average of 165 to 170 seconds. Prop assembly weight is 17.5 pounds which is actually off the chart, but if we extrapolate where it would be on the chart the Medium IVOPROP IFA appears to be around 7500 kg/cm2.

Just food for thought. Sorry about the crappy picture.

Geowitz
07-24-2012, 05:59 PM
More prop info here - http://www.teamkitfox.com/Forums/showthread.php?t=3803

Went with two blade for testing. Runs great now. Will see when it flies as far as performance.

Geowitz
09-30-2012, 04:58 PM
Getting down to the final details...

Empty Weight - 670lbs, balance ended up within the forward range of the envelope.

Taxi test here - http://www.youtube.com/watch?v=eMIIzzkCl_I

Oil temps climb slowly, but steadily so I will need to do some duct work for the oil cooler, but all other temps and parameters are looking great.

About to turn in my paperwork to schedule my airworthiness inspection. Hopefully first flight in November.

rwaltman
09-30-2012, 05:48 PM
Taxi test here ... Hopefully first flight in November.

Congratulations! What propeller will you use for actual flight?

Roberto.

Geowitz
09-30-2012, 06:03 PM
Sticking with the IVO 2 blade medium IFA. It's been working well and really want the in flight adjustability.

Dorsal
10-01-2012, 09:00 AM
looks beautiful, hope the AW inspection goes well.

Mnflyer
10-01-2012, 10:48 AM
Hey Geowitz, that's a great looking Kitfox hope you get the AW and get in the air on schedule, thanks for all the updates.

Geowitz
10-01-2012, 06:14 PM
Thanks everyone! I'll keep ya'll updated. Pretty exciting :)

Geowitz
11-20-2012, 06:07 PM
:D Finally got my airworthiness inspection done and passed without any significant problems- A few zip ties were added here and there, but I'm pretty much ready to go. First flight coming soon. Hopefully in a week or so.

Geowitz
11-20-2012, 06:27 PM
Oh yeah...

Engine update - Baffled in the oil cooler and cut out more exit area in the bottom of the cowling and temps are looking good. Also installed a deflector on the bottom of the cowling to aid in creating a low pressure area to draw out the hot air more. Will get picks later.

Mnflyer
11-21-2012, 11:07 AM
My oh my that is a great looking plane, looking forward to your flt reports.
It amazing how a small deflector on the bottom of the cowl improves cooling.

Dutch
11-21-2012, 02:26 PM
George That is a sweet looking plane. Good luck on the first of many great flights! Again thanks for the help. Those templates are sure going to make my life a lot easier.

Dutch

napierm
11-21-2012, 07:47 PM
Trick from the RV and BD planes: Put a curved bit of sheet metal on the bottom of the firewall. The idea is that it is hard for the slow air inside the cowl to suddenly accelerate around the sharp corner at the bottom to meet the high speed air just below.

You see this on many classic planes where there is a huge flare on the bottom of the cowl needed to eject cooling air during climb out. If you look just after the cowl opening the sharp bottom edge of the firewall is acting as a reverse scoop.

The RV builds in a cooling ramp on the bottom. It adds an inch or so on either side on the bottom of the fuse.

On the BD-4 where there isn't room for a ramp, the trick is to add sheet metal on the bottom of the fuse that sticks forward and curves up into the cowl. That way the bottom of the cowl can be left flat and still eject cooling air with less drag.

BTW, I'm jealous, your plane looks very nice.

Cheers,

Mark



Oh yeah...

Engine update - Baffled in the oil cooler and cut out more exit area in the bottom of the cowling and temps are looking good. Also installed a deflector on the bottom of the cowling to aid in creating a low pressure area to draw out the hot air more. Will get picks later.

Geowitz
12-02-2012, 05:47 PM
For first flight see here...

http://www.teamkitfox.com/Forums/showthread.php?t=4167