Hobbsy

My Feedback: (102)

That sounds for all the world like the LS needle is too rich. Set the HS needle temporarily at absolute peak and lean the LS needle some, if you haven't leaned it at least two full turns from the factory setting it is way rich.

Blazer1

My Feedback: (1)

I will try to lean the low-speed some more Hobbsy, but I am pretty sure I am about as lean as it will go and still transition. The engine has close to a gallon of fuel through it and seems to be running better so maybe I can lean the low-speed a little more. I can not get a consistent idle below 2500rpm which would confirm your rich low-speed theory. The fuel tank is mounted just slightly above the center line of the carb. could this be causing this issue?

w8ye

My Feedback: (16)

The O ring seal between the intake manifold and the head may be bad causing inconsistency in operation?

IKO69

Sign me up too.. I have 3 x 125, 1 x 82, 1 x 100 and 1 x 180...

jdkxtreme

Ok guys I guess it is settled when I put this STM together I am going to use the Saito fa80GK That I picked up at our lebanon swapmeet for 25.00...lol

kevinkenny

I had done much of what you had suggested and I still cannot get the engine to fire so will pass it on to the local hobby shop and hopefully they will be able to identify the problem. Many thanks for all your advice.

Kevin

mike early

Pretty impressive first time post!

w8ye

My Feedback: (16)

You should at least try it. You may find another good deal on a bigger engine later on?

GaGeeBees

My Feedback: (23)

Perhaps a silly question, but could it be something as simple as the linkage? I've seen something similar happen where a throttle cable was used instead of a pushrod.

Rudolph Hart

You could be on the right track there and it's an easy thing to eliminate.Is your avatar a still out of a cartoon with all the birds swinging off some powerlines and getting tangled up? if i'm right it's as funny as and can you post a link so others can see it?

Saito 30 lover can you post your experiences running your engine in and the settings you use? i've got an hour and a quarter up and it finally runs happily without a glo stick attached.Needle setting is two and a quarter turns out and airbleed screw is three and a half as per factory setting,just tried changing the airbleed setting and the engine did'nt like it.Checked the valve clearances and they are identical and tight.How is yours going,there seems to be a lot of them out there and happy owners too.They have the sweetest exhaust note don't you think?

VeeAte

We have a couple of wedgies that frequent our club as well as some kind of hawk. These guys float around on the thermals all day with barely a flap of their wings. I try to steer clear of them as much as possible, but the odd time I have gotten fairly close to one they barely seem to blink an eye. The hawk will sometimes shift a few hundred metres away from us if there are a few planes in the air, but otherwise he doesnt seem too perturbed by our presence.

I guess after thousands of years being the biggest, meanest and dominant creature in the sky it takes a lot to ruffle their feathers hahaha.

Amazing they can stay in the air so long on thermals alone.

w8ye

My Feedback: (16)

The big birds feel an immediate threat and they will fold and drop so don't getting right under them.

There was a guy that liked to buzz the vulchers that were always circling overhead. One day he hit one. The resulting collision knocked a bunch of feathers out of the big bird and the bird took off downwind.

The plane with the broken wing augured-in nearby.

VeeAte

I dont try to go anywhere near them.
As they are so high up and you dont often see them while watching your plane until they are in line of sight with the plane its inevitable you will get close occasionally. All birds are protected in Australia. And no way would I want to bring a Wedge Tail Eagle down. []

So once I have spotted one I keep an eye on his position and avoid flying near him.

There are some videos on youtube of park flyers etc being attacked by magpies. They are mean little blighters. Will relentlessly attack anything near their nests.

bill3388

My Feedback: (18)

I put a new set of bearings in one of my faithful .72's and it seems to be runiing about 300 rpm below what I usually get. I double checked the valve lash and cam timing, tried a different "F" glow plug, and tried a new jug of fuel. I seem to have normal the compression. Even though I think I have the cam timing correct, is it possible to have the cam timing off one tooth and it still would run?

w8ye

My Feedback: (16)

It wouldn't run that good if you were off a tooth

av8djc

My Feedback: (4)

I'm pretty sure I need to replace the rod in my Saito 91 due to my stupidity and hydrolocking it. I knew better but then it's a long story. I've never taken a four stroke apart. Is there any manual to give me a step by step and setting the timing etc? I guess the cylinder has to come off? Any tips on checking the rod for straightness?

I could be a club member now after buying two Saito's in the last month. Converting all my old 2-strokes to Saito. I started with my Goldberg Extra by pulling off the OS 1.08 (really!) and putting a S100 in. Dropped a pound and slowed the plane down yet still lots of thrust for my IMAC style. The 91 is for my Hog Bipe and also makes a good match.

Dave

av8djc

My Feedback: (4)

I tore into it and it looks like the rod is not bent. I had run this "new in box" engine about a half hour on the test stand where it had started to be pretty smooth with a fairly good idle. Then I took it off the stand and mounted it in the Hog Bipe where I tested it out today. Due to the configuration (side Mount), a bad fueler fitting and what not it overflowed into the muffler when filling the tank. I then turned it backwards a bunch, thought I'd cleared it and even turned it forward a few revs. When I put the starter to it it picked up some fuel somewhere and appeared to hydrolock. It semed to make a small noise. Then I proceeded to clear it again and since it turned over fine I started it and played with it some. There seemed to be a lot more vibration than there was on the stand and it didn't idle nearly as well. Hence my assumption that I'd bent the rod.

On taking it apart I noticed the valve clearences were way wide. I didn't measure it but it seemed like about .010. Could that give the symptoms of vibration and poor idle? I changed out my Sullivan fueler fitting with a new one. Also the prop was carefully balanced before the run today so I rule that one out. Any ideas? Somebody chime in so I don't have to keep answering my own post

Dave

JWQ500RC

My Feedback: (2)

It maybe your lsn. On the stand it may have been set ok in the plane do to tank location it maybe set rich. A rich lsn will make these engines vibrate.

w8ye

My Feedback: (16)

Wide valve gaps cause loss of power at top end and valve component damage

you may have a tank height problem

VeeAte

I did the same thing to an ASP .91 4 stroke the other day.
I thought I had damaged the engine when it hydrolocked, but it has been running fine since.

Funny you mention the rocker clearance. This was a new engine so after around 2L of fuel I pulled the rocker cover off and there was excessive play in the rockers. Adjusted them and it has idled perfectly since. It would idle fast before or quit. The idle thing may be settling down in mine because its been run in a bit more. More so than the rocker adjustment.
But it did help.

As your engine had loose rockers as well it begs another question to me.

Is it possible to bend a pushrod when hydro-locking a 4 stroke?

w8ye

My Feedback: (16)

Unlikely

VeeAte

Good to know.

av8djc

My Feedback: (4)

Ok thanks. The vibration seemed to be throughout the range. I'm going to put her back together, leave the cowl off, and play with it again. One thing I did while it was on the test stand just before I pulled it off is adjust the lsn inward to get the better idle. It ended up about flush with the top face of the plastic throttle arm. Appreciate the help.

Dave

w8ye

My Feedback: (16)

Typically the LSN is below the surface of the plastic throttle arm when set correctly. Flush with the surface of the plastic throttle arm is the factory breakin setting

GaGeeBees

My Feedback: (23)

Yes, good for you for recognizing! Here's a link: http://www.evtv1.com/player.aspx?itemnum=12388

You can also find it by typing: "For The Birds animated short" (without the quotes) into Google. Enjoy!