earlwb

I did try the crock pot method, but I think I used the wrong type of antifreeze for it to work well. So my results were not all that good.
But since I have the engine torn down, if it is grungy, I'll use Dawn Power Dissolver on the aluminum parts and scrubbing with a toothbrush etc.
Do test the DPD on a small part of a engine first to be sure it doesn't stain the metal on you. Some aluminum alloys can discolor from using it.
I also don't leave it on to soak as long as the instructions say too.

blw

My Feedback: (3)

The crock pot does a better job faster, but I think a lot of people enjoy sitting with DPD and a brush too. I've left it on Saitos and Evolutions for up to 45 minutes without any discoloring.

Tarasdad

Stripped the first of the two .91s down today. As I thought, absolutely filled with old, gummy, baked on castor residue. Got the bearings out and the front feels okay but not so sure about the rear. Soaking and scrubbing it in fresh fuel to see if that helps or not. Hoping so because if it needs bearings that isn't going to happen for a while. Just got to finish cleaning it up and see what happens.

Well, they were free so I really can't complain, can I?

Mein Duff

A set of new bearings from RCBearings.com would be under $10 for the set probably...unless the old ones are pristine when cleaned.

Tarasdad

Front bearing is okay, rear is toast. When I buy new ones I'll buy both. I can always find a use for the old front bearing, all kinds of little projects it can be used for.

Ernie Misner

A soft wire wheel on the bench grinder cleans and shines mufflers up ASAP. The key is using a soft wire wheel, they are right next to the hard ones on the shelf. No, it doesn't scratch them and actually sets the stage for polishing them if you want to do that.

Ernie Misner

SrTelemaster150

Why do people insist on running castor in Saitos?

After having issues W/sticking exhaust valves/cam lobe wear running castor/synthetic Byron's 4 stroke fuel, I switched to all synthetic Cool Power & have had zero issues since. My engines run on Cool Power stored for 14 years were oiled through the breather & rocker boxes & fire up. No problems. The synthetic oil in Cool Power protects adequately from rust & does not gum up.

An FA 150 that was torn down after having 25+ gallons of cool Power run through it had no detectable wear in the cylinder or cam lobe. I fail to see where castor is needed for these engines especially when the possible issues W/its use are considered.

Hobbsy

My Feedback: (102)

These two valves ran in my high compression Saito 1.50 from 1992 to 2006 and never saw fuel without castor, in fact the first two seasons of its life it ran on Fox 15% fuel with 20% castor as did my Enya .46MKII. Neither engine ever had coked up valves nor did the valves ever stick.

radial1951

*
There are certainly differing opinions here (and everywhere else) regarding the use of castor oil, especially in 4-strokes. I have several different brands of engines, a few Saitos, including 2 radials, but happen to have an OS FS81a (sorry). This is from the OS User Manual:

The FS -81 should be operated on a methanol based

fuel containing not less than 18% (volumetric) castor oil,

or a top quality synthetic lubricant (or a mixture of both)...

It seems that OS don't have a problem running even straight castor oil in their 4-strokes. I wonder why the Saitos are different...

Regards, RossG
radial1951
_____________

ORIGINAL: Hobbsy

These two valves ran in my high compression Saito 1.50 from 1992 to 2006 and never saw fuel without castor, in fact the first two seasons of its life it ran on Fox 15% fuel with 20% castor as did my Enya .46MKII. Neither engine ever had coked up valves nor did the valves ever stick.
[/quote]

blw

My Feedback: (3)

The rust issue is sometimes a hit and miss deal.

Ernie Misner

You won't see much castor carbon build up with out overly lean runs. Most folks would have witnessed the cam lobe wear with straight synthetic fuel it seems like. Could the Byrons 4-stroke fuel have possibly been one of the 4-stroke fuels that is quite low in overall oil content?

Thanks,

Ernie Misner

Ernie Misner

Heres a good demo on Saito bearing replacement. He uses the .82 here. I posted this as a new thread in the Engine forum as well. Thanks to Paul Swany and the Profile Bros. here.

>>> Edit - heck, the Profile Brotherhood's links won't work here. So if you are interested just go to the Profile Brotherhood's web site forums, Engines, and scroll down to Saito 82 bearing replacement thread.

http://www.the******************.com...p?f=18&t=16472

Ernie Misner

Rv7garage

My Feedback: (10)

Just a couple shots of a pretty Saito twin in its natural environment

Tarasdad

I remember the manual that came with my FA-80 recommending against castor oil. I used fuels with synthetic only and had no issues whatsoever. It's only when fuel with castor in the mix was used that I had issues. Now my Fox engines on the other hand....

orthobird

My Feedback: (1)

WOW wow wubzy,

i am in love!!


what a beauty!!

wait a minute here, is that a glow ignition system?

that is way too cool!!

Rv7garage

My Feedback: (10)

Thanks

blw

My Feedback: (3)

There was a Horizon induced contradiction on the castor issue. Saito always recommended using castor.

Tarasdad

The instructions with my engine were from Japan, not the newer ones from Horizon. Saito-Engines.info has the relevant quote from them on their "Fuel" page. This doesn't appear in the instructions included with Horizon distributed engines, only in the original Saito instructions.

I'll keep to a castor free environment for my Saito engines.

SrTelemaster150

The instructions I received W/my 1st FA 150 back in '97 recommended against castor. The newer manuals do not make such a recommendation.

Castor is old technology & some are resistant to change. There's just no reason for it in a ringed 4-stroke.

It's like people using synthetic oil in their cars & still cling to the 3,000 mile oil change belief.

Copy/paste from Saito-engines.info "fuel page" (bolding of text below added for emphasis)


A fuel with 10 to 15% nitro is fine, however higher nitro content (up to 30%) is suggested by Horizon Hobby to be OK (see also the section ‘Special Tricks’). More nitro does provide more power but the fuel cost does substantially increase with higher nitro.

Nitro content greater than 15% is not necessary. If you can afford to buy fuel with 20-30% nitro a bit more power is available, however you might be better off buying a larger engine, or a lighter model, if you are that desperate for more power.

The oil content recommended by Saito and Horizon Hobby is 20%. Horizon Hobby state that oil that is a blend of castor and synthetic is acceptable. Saito instructions (that no longer accompanies engines sold in the US) say the following: “Since the four-stroke engine has high exhaust temperature and carbon is apt to accumulate when castor oil type lubricants are used, avoid using fuel containing them.” This seems to imply Saito recommends fuel with no castor at all. It is not clear that 20% total oil content is really needed as 15-18% seems to work fine and is common with commercial fuels labeled for 4-stroke engines. It is really also unclear that all-synthetic, or a blend of castor-synthetic, is preferred; both are probably OK, however no more than 5% castor with the remainder synthetic oil is usually recommended. Byron 4-stroke fuel has a total oil content of 16% with about 3% castor and the remainder synthetic.

I have heard from some European Saito flyers who are mixing their own fuel with 10% total oil content. No adverse effects have been reported. However 15% to 20 % is a safer blend.

In summary, any commercial 2-stroke or 4-stroke fuel should be fine, provided you make sure the castor oil content is low, with mostly synthetic oil. The only difference between commercial 2-stroke fuels and 4-stroke fuels is the total oil content (4-stroke fuels typically have 2-3 % less total oil content compared to 2-stroke fuels).






[Saito Home Page]

mike early

I use Wildcat and it's 80-20% synthetic-castor blend. It's wonderful. With changing weather conditions, I sometimes run it too lean and have never experienced any damaged from that.

blw

My Feedback: (3)

I'm sure some folks can run low oil content and synthetic and get away with it. Let's face it, some people aren't too interested in tuning their engines right, or they get it wrong until they learn. That's when engines get burned up with synthetic only fuel. Look at the old 72 with the old style backplate and chronic air leaks. The engine would unpredictably run lean. Bill Robison had some pretty good evidence of early cam wear with fuel without castor.

SrTelemaster150

So in other words, a properly tuned engine that is running properly does not need castor.

Better to tune properly than run an oil mix that will eventually gum things up as assurance that one doesn't burn up an engine W/poor tuning.

blw

My Feedback: (3)

You wouldn't need to worry about the gumming issue if a small percentage were used. Taking the right steps when storing engines goes a long way too.

w8ye

My Feedback: (16)

If you are going to be this way - you must listen carefully to your engine - land and adjust the needle valve on a slight lean mixture infraction caused by the sun going behind a cloud or flying through a thermal.

I always feel of my engines when I land and have noticed them sometimes very dry when using a fuel with marginal oil content.

A four stroke can feel very dry to wiggle the prop on shutdown and you can still find some residual oil in the crankcase. I don't think the residual oil in the crankcase to be a good indication of your fuel's oiling capacity.

mike109

G'day

In my club there are castor and non castor users. A few of the non castor users have no problems. They tune properly. But some others cook engines. They don't tune properly. The castor users (I'm one) don't cook engines but we do occasionally have blocked carbys when an engine was stored without being run completely dry and the fuel residue in the spray bar dries out and forms a plug. I'd rather have this problem than a cooked engine. The solution is usually to block the muffler and turn the engine over with the starter.

I have a Saito 120 in bits which was given to me to sort out. It has large black vertical stripes on the bore and I suspect it was close to being seized. It came from a non castor user who was notorious for lean tuning. It also has the muffler pipe threads ripped out, the mounting holes all over size and totally rusted bearings. Some people just have too much money and take no care of their engines.

So I guess it boils down to this. If you can tune you can use synthetic only fuel and have no problems. If you can't or are learning then a little castor is good insurance. After 50 years or so, I am still learning so I use castor.

Mike in Oz