Capt Lou

W8ye:

I disassembled my Saito 65. All the internal parts look good. I've cleaned them and now I will order parts. I need your help on the cam timing. My manual states that the cam timing mark should be at 6 o'clock while the crankshaft is at 12 o'clock or top dead center. I believe I know what this means but I would appreciate your guidance to confirm my understanding. I assume that the cam timing mark is the hole mark on the timing gear and that this must be at 6 o'clock while the cranshaft connector for the piston rod is at 12 o'clock. Is this correct? Help?

Thanks for your help in advance.

wjbender

Let's hear some pro and con about using Omega Vs Cool power in a Saito. i just bought my first one a used 82 (2007) from a guy in my club. I like the extra protection castor provides and thought that I would use 15% Omega. Is this a good choice for this engine? I will be installing it in a Hangar 9 Ultra Stick 40 size.

Michaelh

My Feedback: (4)

One pro on your setup is you could get away with lower nitro .

jb86

My Feedback: (8)

APC15x4W (W for "wide") should be about right for that engine. tach it, keep it under 10k at WOT (max WOT, when tuned for peak should stay below 10k), back off 200-300rpm.
http://www3.towerhobbies.com/cgi-bin...?&I=LXFGW1&P=7
the 14x7 is a pattern prop. good for fast smooth aerobatics, not enough "bite" for slow 3d flying.

from the horizon website, saito 91; Benchmark Prop:14 x 6 Zinger @ 9,100 (my old OS 90FS w/pump got almost 10k w/MA 14x6 and 15x4W about the same). add 1 inch to diameter, subtract 2 inches for pitch, the rpm should stay very similar. except, the 15x4 is "wide", that will lower the rpm a little. alot of flyers use the apc 15x4W on the .82, it is a just a little but too much, spool up is too slow. i have considered using the MA 15x4 (not wide) on my .82.
jon

Michaelh

My Feedback: (4)

My .82 can swing a 14x6 zinger at that rpm though.

Chuck381

Dave and Mike109,
G Day to you Mate! Ok so I puled the valve covers to chek on the push rods, low and behold the intake rod had jumped out of it's socket! I re adjusted them both again, ensuring the engine was TDC, re checked and re checked and did I mention re checked the valve clearance and TDC! I put it all back together installed the cowling and prop, fired it up and put the Tach on it. Hold on to your seats for this! @ idle it is a scary 1800RPM, full throttle the reading I got tonight was 88-9000 RPM. I about fell out and thought I had beter check it again withthe Tach, and as I made small HS idle screw adjustments I dialed it in a litle rich @ 8800RPM! WOW and that is 16X6 APC prop, 15% Cool Power Synthetic and at sea level with the OS F plug. Not too sure how I managed to mess it up the first couple of times adjusting the valves but I will keep an eye on them till I feel comfortable. Again thanks for the advice and assisteance.
Chuck

Hobbsy

My Feedback: (102)

Sneaking up on the peak is good. That way you can tell when it goes slightly lean and starts to slow down, just richen back a little and you won't have to go over to the next farm and retrieve your prop, You dun good.

TimC

You sure have a good .82. My Saito .91 turns a 14x6 MAS about 10,000 peak.

Mikecam

I'm putting in my first Saito 4 stroke, a 125 into a Top flite 1/7 P51. Would you suggest I use a onboard glow driver or is it not required. I should have no trouble tuning the engine and it will be inverted. Thanks

http://www.greathobbies.com/productinfo/?prod_id=MCD466

GSNut

My Feedback: (8)

Just break in first and probably use a on board glo driver to help !
You will like it there, am sure esp. inverted.

Cheers

GSNUT

Club Saito # 57

Vinnie6

I am running a Saito .91 inverted. I do have onboard glo and love it. It idles very well without the glo turned on, but I like the extra insurance. I went with the Electrodynamics brand. I had SR make me a single cell 3400 maH NiMh pack for power. The engine is VERY easy to start by hand inverted. Did anyone read Clarence Lee's engine clinic in this months AMA magazine? He suggests 4 strokes run better inverted than 2 strokes do inverted because the glo plug is offset on the 4 stroke, not at the top (bottom) of the cylinder like a 2 stroke. Thus it is less likely to flood out.

Michaelh

My Feedback: (4)

Yeah I posted numbers up a while ago.The .82 should be turning an 14x6apc at 10,000.
The Zinger really loads it and flight performance to me is erratic,same with the pro and Xoar.Uplines really suffer.
I run the 14x4w on it now and it runs out of some peoples comfort zone @ 11,000 peaked.

What type MAS are you running? K, scimitar etc. ? A guy does good at the field with the Scimitar on his .82 dont know the numbers as he does not tune like that.

jleehey

OK this one has me stumped.

My old dependable Saito 91 4-stroke has started sounding like the valves and piston are hitting. The noise is horrible. It sounds like the engine will self-destruct momentarily. But the engine still runs great and has plenty of power.

I had it apart last week and could find nothing wrong except for quite a bit of soft carbon on the piston head and cylinder head. It wiped off easily (strange!). The bearings, crank, connecting rod, both rod ends, piston skirt all look great. I adjusted the valves (again) and put it back together and the noise is still there. Actually, it is getting worse as I fly it.

Sticking exhaust valve? This might explain the carbon, but the noise? I do not have a compression or starting problem.
Worn valve guide? Maybe the valve is flopping around?
Weak valve spring?

Any ideas are welcome. I don't know what to replace.
Thanks,

w8ye

My Feedback: (16)

Maybe you have a broken engine mount? They will hammer to beat the band if something is loose about the mounting.

Chuck381

Hobbsy, Just to let you know I went to the flying field after work today and flew my EDGE 540 with the Saito 125 after re adjusting the valves and it checked out great at the house. I wanted to make sure it was going to act right in the air. I fueled her up, started right up, let her warm up for a minute, got the Tach out, checked out high and low, 19 low-88 high! So up up and away she went! Right on she flew with great power! Verticle all the way! Hovered (under half throttle), pulled with tremendous authority! I just wanted to say Thank you again fro the advice and help! I only wish I was going to be here for the next 9 months to fly her! I will pickle her up before I go and hope all is well when I return.

Chuck
You GI in the Sky!

Hobbsy

My Feedback: (102)

Glad it works good now, You live in the same town as our old sidekick William Robison lived. Did you know him? I miss the phone conversations he and I used the have. I still bug w8ye, BLW, Jim of RCSpecialties, Brian Cooper eta al. Thanks

Capt Lou

W8YE:

Can you help me with this?

Thank you

WMB

My Feedback: (1)

I need a cylinder and a ring for a 65. Couldn't find them at Horizon hobbies. Any other places for older parts?
Thanks, MikeB

w8ye

My Feedback: (16)

You can get a ring from Frank Bowman

Frank C Bowman
1211 N Allen Ave
Farmington, NM 87401-3568
505-327-0696
[email protected]

Also the Saito 56 ring fits the 65

You can get the 65 cylinder here but it is on back order

http://www.horizonhobby.com/Products...rodID=SAI6501C

Capt Lou

WMB:

I had the same issue with Horizon regarding a FA-65. The problem is that they have the parts for a 65 but don't show the engine on the pull down menu. Go to the horizon site and insert these part numbers in the search tab: SAI6501C (Cylinder, left) and SAI6509 (Piston Ring). I just ordered several parts for my 65 from Horizon and this is how I identified the parts. For your information, if you have the Saito manual that came with the engine, you can find all the parts numbers for your 65 on their "Parts List" pages and when ordering from Horizon insert "SAI" before the part number.

Hobbsy

My Feedback: (102)

Lou, the dimple in the picture #1 goes straight down when the crankpin is at 12:00, if your lifters don't have phlanges you can insert a pin in the intake lifter bore and hold the cam in the correct position using the hole in picture #2.

WMB

My Feedback: (1)

Thanks guys! that helps, MikeB

Hobbsy

My Feedback: (102)

Cap, if you haven't yet timed the .65, here is how you can verify that you have it right, picture #1 shows the intake valve just starting to open, the cam has closed the valve lash.
Picture #2 shows both vales open equally at TDC
Picture #3 shows the exhaust valve just closed.
Picture #4 is the beginning of the compression stroke
Picture #5 is the beginning of the exhaust stroke.

Hobbsy

My Feedback: (102)

Lets talk about those pic, one at a time
Picture #1, the intake valve is opening about 20 dgrees BTC on the exhaust because the exiting exhaust has momentum that leaves a partial vacuum in the cylinder so opening the intake valve early gets the intake moving creating more time for cylinder filling.
Picture #2 shows both valves partially open at the same time, this allows that partial vacuum to assist the intake comming in.
Picture #3 shows the exhaust closed about 20 degrees ATC creating about 40 degrees overlap, the exhaust is out and the intake is well on its way in.
Picture #4 shows the beginning of the compression stroke and the intake just closed. The intake also has momentum and continues to flow inward even thiough the piston has started upward.
Picture #5 shows the exhaust valve starting to open, as you can see there is virtually no leverage left in the combustion stroke so there is a huge benefit from getting the exhaust started out early, that way the piston has to do a lot less pushing to complete the exhaust exiting. I think I covered it although with much brevity. Jim, if I screwed anything up please point it out.

w8ye

My Feedback: (16)

Hobbsy,

Thanks for fixing Lou up with his timing procedure.