freeonthree

My Feedback: (1)

Ya won't get service like that at the gas station. lol

bldrums

How could I have overlooked the low end needle ? Maybe because Ive never touched it since the engine was new. Matter o fact, Im still running the original (saito?) glowplug. Better check that valve clearance too while Im into it.
I just admitted to unacceptable engine maintenance. I hope this doesnt cost me my Club Saito membership. []

Ken6PPC

bldrums, if you have never adjusted the valves, I would certainly check them. They wear fastest when the engine is new. That is part of "break-in".

Unlike w8ye and freeonthree, I don't think you should richen the LSN. If you have never adjusted it from the original factory setting, it is too rich now. You will have to lean it to make your engine run better. (Adjust the valve gap first!) Turn the LSN clockwise 1/8 of a turn at a time, until the throttle transitions well. The idle RPM will likely increase as you lean the LSN, and you will have to adjust that for a low enough idle speed. If you turn the LSN in too far, it won't idle well, and will die when you throttle up. (Similar to what it is doing now, but for the opposite reason - it will be too lean, while it is too rich right now.)

w8ye and freeonthree, do you agree with this, in light of the fact that bldrums says the LSN has never been changed from the factory setting? Saito's manual even acknowledges that the LSN is set at the factory to run very rich.

TCrafty

Thanks for the input guys! I'll probably be getting new bearings soon then. It's not a big problem other than i've got to hang the plane out to dry when I'm done flying. Good to know that there is an alternative to the fuel-bath flyer that I've got now and that I didn't do something wrong when installing them. Great info.

bjb6723

I have a question about the FA 80. I bought one used about 3 months ago for my Showtime 50. Well I FINALLY got to fly today. The engine seemed to be lacking power BIG TIME. It barely got the plane off the ground. I spent about an hour trying to get the mixture set right. Well I did a couple laps of the field then landed. I noticed that there was what looked like a leak coming out of the cowl from the head. I am guessing the head gasket is leaking and I need to rebuild it. I am also guessing thats where all my power is going. This is my first Saito and would like some ideas as to what it could be. Thanks for any help you can give!!!!!

freeonthree

My Feedback: (1)

My 80 doesn't have a seperate cylinder head, it's part of the cylinder. All my Saito's are that way... 56, 65, 72, 80.
First I would make sure the valves are adjusted correctly, there's a gasket on the glow plug, the vent nipple has a hose on it, and that the oil isn't coming from the front bearing. The bearing may not have a rubber seal. If the engine was apart recently, the cam timing might be off too, causing the lack of power.

bjb6723

Thanks Free. Do you know where I can get a manual or instructions on how to do Valve adjustment and cam timing? Like I said, I got this used, so I am unsure of the history. Thanks!!

freeonthree

My Feedback: (1)

Remove the carb. Remove the backing plate. Remove the valve covers. To remove the cylinder. Note that the smaller pointed end of the rods go up (rocker arm). Do not pull the piston out of the cylinder enough to let the ring come out of the cylinder. Silde the connecting rod off the crank pin, and remove cylinder. Remove the cam cover. To set the cam timing, with the crank pin at TDC, the dot on the cam gear should be straight down.I stick the gasket to the cam cover first, and use a single edge razor blade to hold the cam gear in place until the cam cover is all the way down. With the engine faceing you, hold the blade in your right hand, and it will be easier. It is for me anyway... Reinstall cylinder and push rods and tubes. Remember, pointed/smaller end of push rods go up into the rocker arm adjuster. Finally, set the valves at .002 to .004 (top dead center compression stroke). Reinstall backplate and carb. These engines are fun to take apart and put together, and their real easy to work on, just take your time. While the cylinder is off, it's a good time to feel the bearings, you can feel em good then...

Ken6PPC

[link=http://www.horizonhobby.com/ProdInfo/Files/SAITO_Small-Medium_single_cylinder_Manual.pdf]Saito Small-Medium Single Cylinder 4-Stroke Engine Instruction Manual[/link]

That manual takes a little time to download, so be patient. The valve adjusting procedure is on page number 9.

w8ye

My Feedback: (16)

http://saito-engines.info/maintenance.html

freeonthree

My Feedback: (1)

Cool, now I have the manuals too !

SigMan

My Feedback: (21)

well, today i seen first hand what a prop can to fingers, a gentlemen stuck his fingers in the prop at a airshow in evansville, indiana. and blood went everywhere. bout 10 minutes before it happenend, i told my wife to look at that guy stopping his engine by grabbing the prop nut, man he's crazy i told her ! then we had just walked past him while viewing the planes on static display when we heard the thuds of fingers in a prop, stopping a engine ! OH MY GOD ! the blood coming out of his fingers was horrible. just hope he's ok. i guess the moral of this story is "rethink bad habits"

rajul

My Feedback: (58)

That's another grim reminder that safety comes first, and always respect the prop!

N1EDM

My Feedback: (2)

I might suggest that the lack of power might be caused by one of the pushrods has slipped out of its 'nest' in the rocker arm. That happened to a friend of mine.

If you find this to be the case for you, please check that the pushrod and the rocker arm are undamaged from running.

Freeonthree, thanks for the tip on using the razor blade. That's a new one for me. I appreciate your sharing that with us.

Bob

RVM

Since my plane is currently out of commission I thought I'd put my .82 back on a bench and break it in a bit more (good excuse to run my engines - I love tinkering with them). For some reason the needle settings were really inconsistent. It may be because the tank is about 2" - 3" lower than the carb, and the tank was also moving around a lot. Could this cause the engine to lean out while at full throttle? I also am used to running it with a regulator. Anyway, at full throttle, when peaking the engine, it would just suddenly lose RPMs very rapidly and die. I'm 99% sure it is because the engine went way too lean because of the inconsistent fuel flow. Once or twice you could hear fuel sizzling in the muffler and a bit of smoke coming out the exhaust. I did this 2 or 3 times trying to get it adjusted before I backed off until I could get the fuel flow to be consistent (which it eventually did, but I didn't change anything - I think maybe the engine just needed to run awhile to blow all the air tool oil out of it). The engine seems to be fine, but I am just checking to see if this has the possibility to cause any permanent damage.

I did notice that the engine is leaking some compression from both valves when turning it over, but the power seems to be normal, and when filled with after run oil the leak is almost non-existant, so I'm not so worried about it. I've read some valve leak is normal anyway.

I did peak it at 9900RPM today with an APC 14x6 on 25% Omega. I figure with another gallon or two it should easily break 10k. 30% should have it around 10300 or so I would imagine. I really want to try a Graupner 14x6.

Hobbsy, I've got some Corrosion X on the way finally. Yay! Does this stuff break down carbon and varnish in addition to protecting?

Gstan

This is a great thread. I just ordered a Saito 72. Is there a thread that tells the proper break in?

RVM

If you follow the instructions in the manual you will be fine.

blw

My Feedback: (3)

Gstan,

The manual may seem simplistic, but follow the instructions while breaking it in. Expect it to guzzle fuel at first, and maybe shake some. It will settle down and start becoming more economical. Once your 40 minute break in period is done, you can either run it some more or put it in a plane. It will take about a gallon of fuel to really break in, or be well on the road to it. Someone will help you along once you get it flying. Just ask. Also, read some of past posts on how to start leaning it out as you break it in.

Hobbsy

My Feedback: (102)

Robert, I think that tool oil is coking on your valves, of all the Saitos I have, none have any valves that leak, you'll like the CX, it will not let castor congeal.

RVM

Cool. Cannot wait until it gets here!

How do I clean it off the valves?

Hobbsy

My Feedback: (102)

Jim, per our phone conversation here are some pictures of the cooling fins and vent placemant on the .45 up through the .62.
Pic. #1 is a .45 top view, Pic. #2 is .45 side view, Pic. #3 is the .50 top view, Pic. #4 is the .50 side view, Pic. #5 is the .56 top view, Pic. #6 is the .62 top view, Pic #7 is the .62 side view, Pic. #8 is the .50 and .62 side, same cooling fin config, different crankcase on the .62.

Hobbsy

My Feedback: (102)

Here are the valves from my 17 year old Saito 1.50, it's first two seasons it was run using Fox 15% fuel with 20% castor, then one season of Byron's and since 1993 only WildCat 10% and 15% Premium Extra. On both sides of the valves the cylinder is clean, I don't know whether to be so bold as to credit the WildCat fuel for that cleanliness, but if someone asked that's what I'd say. My .80 which is the same age and run slightly more is just as clean.

AMB

Hobbsy and the rest of the group have a new spacewalker ARF they show a 70 to 91 4stk having 1 saito 91 and 2 72s NIB guess I will have to make a decision comments welcome
it is the great planes version martin

my most reliable engines no dead sticks any of my diesels and my 2 Saito 56s

RVM

Dear God you guys won't believe what just happened to my .82.

It blew up. Not literally, but close enough.

I was running it on the bench today to try and clear out the air tool oil I had been using as an after run. Hobbsy thought it might have been causing a bit of build up and thus some valve leaking. I cleared it out and ran the engine for a few minutes and voila, that must have been it. The engine was running like a Swiss watch. Since I still had about 12oz. of fuel in the tank I decided to go ahead and let the engine run it out - more break-in time is always good and I don't like to mix fuel that has already been dispensed back into the main container. I peak the engine, 9900RPM with an APC 14x6. I idle it, peak the idle, it dies when slamming the throttle to full. Richen it up a bit, transition is flawless. I richen the engine to 9600RPM and set the throttle to around 6000RPM. I am about to go inside to get some water while the engine runs the fuel out when I hear a noise like someone letting up a clutch too fast without enough throttle - a metallic DINK sound, sort of. The engine stops dead. I go to turn the prop and I hear some rattling. Take intake valve cover off, looks fine. Take exhaust valve cover off... umm, big problem. This is no bueno! A piece of the rocker arm falls out, the spring goes flying who knows where, I can't find the valve retainer and the valve guide (you know, the big brass thing permanently inserted into the head) is not in the head. It's resting in the place where the valve spring should be. The valve itself is still in the cylinder. Maybe the other pieces are too.

Anyway, I think this engine is toast. Only 1.5 gallons through it, and it was a replacement for another .82 that I could not get running right. To top it off this .82 must have been one of the "good ones", in that it seemed to pull really strong numbers relative to other .82s.

I'm not upset at all. Mostly, I think I'm still in too much shock to be upset.

I will put up some pictures later tonight when I find my digital camera.

*sigh*

w8ye

My Feedback: (16)

The ole gal dropped a valve.

I had a 72 do that once. Horizon put the parts back together and it has run ever since for about 6 years now.