SigMan

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oops! sorry Bill...my bad ! [sm=spinnyeyes.gif]

PlaneKrazee

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William Robison

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[b]Phil:

I don't make a big thing out of my name being misspelled anymore, I used to be really picky about it. Now, so long as official documents get it right I'm happy.



Oh well.

Bill.

William Robison

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[b]All manglers of my name:

Apologies acccepted.

Bill.

William Robison

My Feedback: (3)

[b]All:

Current member list is [link=http://www.rcuniverse.com/forum/m_3306814/anchors_3338246/mpage_4/key_/anchor/tm.htm#3338246]here[/link] in post numbers 77 and 78. Number 77 is in alphabetic order, #78 is in numeric order.

Bill.

William Robison

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[b]Ohmigawd!!

Just heard on the radio of another William RobiNson - he was just arrested for murder in Pensacola.

Bill.

Hobbsy

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Bill, I have a friend who builds my brothers racecar trannys his name is Leland Robeson. He could hardly believe there is a hemi model airplane engine.

William Robison

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[b]In that spelling we have to remember Paul Robeson - an extremely good singer, but also a devout communist.

Bill.

proptop

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I thought it was Bill Robison who sang "Ole Man River"...but I see it was Paul Robeison...

And here I thought you were famous Bill?!

Well...you are famous...here...

Or would that be infamous?

Haw!

William Robison

My Feedback: (3)

[b][PT:

In the movie production of Show Boat (1950-1951?) it was Paul Robeson. Ava Gardner and Howard Keel were in that production also. The 1988 revival had Theresa Stratas, Frederica von Stade and Jerry Hadley (all opera singers) in the lead roles, and Bruce Hubbard played Joe, the "Old Man River" soloist.

Bill.

khodges

My Feedback: (1)

William-or Bill, or Will, or Mr. Robison, when you speak of "mushroomed" cams, are you speaking of a shape that increases the length of time the valve is fully open? I know this is somewhat different from duration, which I mean to be the time the valve begins to open until it is fully closed again. Does this improve scavenging as much as it does total airflow?
When I was roadracing (motorcycles) back in the '80's, we messed with cam grinds, overlap, and modifying the total timing (valve) to change the power band to suit track conditions.

When is Saito gonna get with the plan and come out with a 4- or 5- valve design? The top end would be pretty busy at 11 grand, wouldn't it?

The "other" RobiNson--Will Robinson, of "Lost in Space" from the '60's WARNING! WARNING! You are in grave Danger, Will Robinson--remember the robot?

William Robison

My Feedback: (3)

[b]KH:

Not mushroomed cams, but the tappets. The increased diameter of the cam end of the tappet will increase the valve duration and overlap with no other change. In the first attached picture the plain tappets are in the left column, what I call "Mushroomed" tappets are on the right.

This composite shows all the external differences between the old style big block engines and the "High Cam" versions. Also shown is the original "S" cam, just used for a short time in the original FA-120S. If you see a 120 with a curved intake pipe instead of the cast pipe it's an "S" model, the hot one. The later "S" 120s had the cast pipe and a normal cam, but still with the wide headed tappets so they were still a bit hotter than the early ones.

Second picture is the hot "S" 120. See the intake? Third picture is the standard 120 cylinder next to the "S", both shown with the intake pipe. Finally, current production FA-120S showing the return to the cast intake.

Bill.

William Robison

My Feedback: (3)

[b]Oh, one more thing. I prefer to forget "Lost in Space," and also "Saturday Night Live" - "Oh NO Mr Bill!"

Haw.

Bill.

khodges

My Feedback: (1)

I quite understand.

William Robison

My Feedback: (3)

[b]All:

Just found another picture of the hot version of the FA-120S, shows the intake pipe better, and you can see the muffler that came with it. Second picture is the outlet end of the muffler. Exhaust restriction? What's that?

Haw.

Bill.

beelzebubishere

My Feedback: (1)

This is just WRONG!

My new Saito 56 came in from Cheif this week, but was busy, and didn't open the package till Friday.....I'm supposed to put THIS, in a model airplane?

It's a....JEWEL...it oughta be on display somewhere....and I'm gonna cover it up in a J-3 cowl....this is just wrong....now I want another one, or 2....well, let's just say MORE![sm=tongue.gif]

SigMan

My Feedback: (21)

kliff,...it happens to all of US !

ledsled

My Feedback: (1)

I have a Saito 90 that just dosen't have that many hours on it, about a year old. When it comes up to full RPM 9000 to 95000, runs for a short time then a screetching sound kicks in and I shut it down. It's not too lean, plenty ritch, and once I shut it down it's not that hot to the touch.

Some one at the field suggested to put new bearings in it. Could a couple of nose in take offs damage the bearings?

There does not seem to be any slop in the crank, and I would'nt expect it to have any for only a year or so old.

My OS 90 4cycle about 5 years old with no wear.

Any Suggestions, I love the Saito, idles great, sounds great?

Also, Ive never changes bearing any instrcutions on the steps?

Help

The PIPE

I had JUST this sort of problem crop up on my Saito 56 while breaking IT in 2-1/2 years ago...

Dear LedSled:

The PIPE here again...I had this EXACT "bearing shriek" problem come up in the Spring of 2003 while breaking in my Saito 56 four stroker...and from my reply in a thread at http://www.rcuniverse.com/forum/m_67.../tm.htm#670560 , here's my account of that occurrence and my solution to it...!

Any additions to the original text will be enclosed in [brackets] to clarify what I was saying..."here goes"...

"The Saito 56 I have, started running with a 12 x 6 Master Airscrew fiberglass prop, at the "fast idle" setting recommended by Saito, at around 3900-4000 rpm for about a GOOD 30-40 minutes. The fuel is FHS Red Max 10% nitro, 17% all synthetic oiled [four stroke] fuel, with the oil content "spiked" up slightly to about 20% for that first tankful.

After the fast idle initial run-in, I started running the 56 at full throttle, but at a BLUBBERING rich setting that made the engine emit SO much gray smoke that it looked a bit like I was "fogging for bugs" at my club's flying site.

I gradually leaned out the motor, but a mysterious SHRIEKING noise started to intermittently pierce my hearing...the it became more "continuous", so I stopped running the engine, removed each of the valve covers, and tried squirting a GOODLY "slug" of Marvel Air-tool Oil into each open valve cover and DOWN THE PUSHROD TUBES to really SATURATE the camshaft compartment and crankshaft bearings!

Re-starting the 56 seemed to bring back the "shriek". but I then stopped the 56, waited a short while, and tried spinning it over with my starter, with NO glow plug power or fuel feed to the motor...and it SEEMED that the shriek might be "over"...connecting everything back up, and restarting the engine yet AGAIN "this time" brought out that GREAT four stroke sound, with NO shrieking noise, so the Marvel Air-Tool oil seemed to have done its job-and the shrieking has NOT come back since."

Marvel Air-Tool Oil should be available in most any well-stocked auto parts store (particularly a REGIONAL chain store...it's NOT as likely to be in a national chain auto parts place) in 4-1/2 ounce bottles...and where our model engines ARE essentially "air pumps", if they were NOT burning FUEL in them, that Marvel Air-Tool Oil has emerged as a PREFECT solution to the bearing shriek problem...AND to "pickle" your four stroker in as an after run and long term storage oil.

Hope this tip helps make your Saito "mill" LESS prone to "getting scared" and start SHRIEKING again...!

Yours Sincerely,

The PIPE!

ledsled

My Feedback: (1)

The PIPE,

You hit this one on the head. That's exactly what mine has been doing. It happened at the field at first, so I brought it home thinking I must have run it too lean. So I fired it up and thought the SHRIEKING was gone. After a couple of minutes up at full rpm it came back.

I bet I don't have 30 flights on this one. I'll float the lifter tubes with this Marvel Air-Tool Oil. I've heard of this oil before. One of the retired guys at the field flys a lot of big 4 stokes and talkes about his oil all the time. Do you know if the FA91S has bearing on the cam?

Thanks for your help!

William Robison

My Feedback: (3)

[b]LSled:

All Saitos have cam bearings, but if you mean ball and/or roller bearings, no. The camshaft has bronze bushes that run on a 4 mm steel shaft.

An alternate way to oil the cam, its bearings, and the tappets is to put a big slug of oil in the crankcase, then hold the engine nose down to get the oil to run up front, then angle the engine back a bit to get it all into the cam chest.

Other ways to get strange noises in a Saito: A seized crank bearing sliding the balls instead of rolling them, this is rare, almost unheard of. The other is an assembly problem, not leaving enough clearance in the timing gears. This is set by selective thickness of the cam box gasket. If you always use the gasket from the engine kit you're OK. If you have too much clearance the typical "Click" as you turn the engine will be louder - it's the intake tappet pushing the cam forward against the gear teeth.

Bill.

Hobbsy

My Feedback: (102)

Bill, my Saito 1.50 has always had noisy timing gears, but the noise never gets better or worse, it turns into a whine at high speeds.

William Robison

My Feedback: (3)

[b]Dave:

With the gear noise getting louder at higher speeds, and therefore higher temperatures, you might have too much clearance in the gears. Sometime when you feel up to an evening's enjoyment let me know, I'll post the way to check and adjust the lash. Not hard, you just need your feeler gauge and normal metric allen keys. Oh, a micrometer too.

Bill.

Hobbsy

My Feedback: (102)

OK Dubya R, I have all that stuff, I'll do it as soon as I build a decent workbench. I use any excuse to work on an engine.

ledsled

My Feedback: (1)

Hey thanks guys,

In addition to flooding the lifter tubes, I was thinking of pumping the crankcase full through the tap and letting it set for a couple of days. Sounds like nose down would be optimal.


When I turn it over I don't hear or feel any clicks, so I hope it's not the cam bearings sliding.

I also just acquired a an older YS120 on a Ultimate that has not been run in the last year or so. I plan to pump it full as well.