Hobbsy

My Feedback: (102)

What rpm are you getting with the 14x4, I know nothing of these popsickle stick props, they don't make sense to me. The .82 loves an APC 14x6.

RVM

10,000RPM on the 14x4 and about 9350 on the 15x4. The engine responds normally to needle changes with the 14x4, but it is as if the needle was deactivated when running the 15x4. I literally turned the needle almost all the way in (maybe 1/2 turn out) all the way to where the needle was hardly on at all (5 turns?), and there was absolutely zero change in the sound or RPM of the prop. I switched back and forth quite a few times with the same results.

I think I have an APC 14x6 I can try tomorrow. Not sure if it will fit in my spinner though, but still worth trying. The balance on plane is so close to the edge that I think losing the weight of the spinner on the nose might make it too tail heavy to be safe to fly. lol

rajul

My Feedback: (58)

Bill, is pharmaceutical castor oil degummed? I remember asking this question a while ago, and the answer seems like it is not?

William Robison

My Feedback: (3)

Mike:

Baker's AA castor oil is by definition degummed, and it's usually first press. Pharmaceutic castor oil is also Baker's AA with the addition of being checked for ricin content.

So the only real difference between Sig and USP is that the castor oil from the drug store is safe to drink as a laxative, with the Sig you take your chances if you're constipated. Haw.

And of course, the USP costs more.

Both are perfectly OK for use in fuel.

Bill.

rajul

My Feedback: (58)

Bill, What does the abbreviation USP stand for?

William Robison

My Feedback: (3)

United States Pharmaceutic. Ergo, USP.

Bill.

rajul

My Feedback: (58)

Can you differentiate from the color of castor oil, whether it is degummed?

Bone

Hobbsy,

Thanks for the pic & explanation re your venting experiment. As you mentioned, yours seems to work best with both 2 vents open to the atmosphere. On the other hand, when you connect the rear vent externally to the cam cover, the gases can choose with pathway suits it best (ie: internal thru the engine or via the tubing). Mine differs slightly in that the rear vent is plugged & that 100% of the gases MUST pass thru the internals before entering the atmosphere. Am looking forward to testing it next weekend

William Robison

My Feedback: (3)

Mike:

Unless it's dyed I've not seen any "Good" castor oil that wasn't perfectly clear and colorless, or at most a very slight tinge toward tan color, but still clear with no visible solids.

When mixed into fuels containing no nitromethane the mix will stay clear. With nitro in the mix sometimes, depending on the percentage nitro, you can see whitish flakes when the fuel is cool. Don't run it with the flakes visible, they can clog the spraybar. Either allow the fuel to warm, or if you're flying in cold weather go to your local drug or paint store and get some amyl acetate, also known as "Banana" oil. A little bit mixed into the fuel will make the solids go back into solution, and keep it from happening again. Very seldom happens even at 30% nitro though.

Bill.

sundancer007

After a prop strike at WOT, im changing out the bearings in a low run saito 125. What will be the best bearings to use vs cost and durability? Ceramic or high speed boca??? Since Im switching bearings, should I switch to a different fuel other than YS 20/20. Both airframes are 3D type, not high speed. The people like Will Robinson and others provide tried and tested info that I trust. Its a pleasure talking with you folks.

William Robison

My Feedback: (3)

Dancer:

It's your choice, but RC_Bearings.com sells the stainless/ceramic composite bearings at about the same price Boca charges for the HS bearings. And if you get the HS bearings from RC_B they are less expensive yet.

To me it's a "No-brainer."

Bill.

KenVC

My Feedback: (7)

Help! I crashed my AT-6 with a brand new Saito 125. I broke the head where the exhaust is connected. Horizon has been out of stock for two months and say they won't be in stock until the end of Jan. Does anyone know of one for sale? I love the Saito engines but am very disappointed in Horizon for not stocking parts and then back ordering for months.

w8ye

My Feedback: (16)

About $30 if you remove the jug and send it to him

Lee, Clarence F.
10112 Woodward Ave
Sunland, CA 91040-3342
(818) 353-7356

rlmcnii

My Feedback: (3)

rajul,

United States Pharmacopeia is the organization which sets the standards for the purity of substances used in medicine and supplements. When you see USP following the name of a substance it is pure enough to ingest. It is also used as a grade of purity for other chemicals. Interestingly, it does not denote the highest grade of purity.

As WR notes, it is evidently sufficiently pure for Saitos!

KenVC

My Feedback: (7)

Thanks for the info. I drive past Sunland once a week and will drop it by. I had heard about Clarence but in regards to glow plug stripped threads.

proptop

My Feedback: (8)

Can castor go bad, as in spoil or get rancid? A friend has had some on his shelf for many years and he offered it to me, but I'm not sure if I should use it?
One bottle still looks clear, the other (different brand ) slightly amber in color...
Does the smell change as it ages? This stuff must be 20+ years old, and reminds me of Karo syrup.

w8ye

My Feedback: (16)

I have some that's 45 years old. It is slightly amber in color. I came across the bottle yesterday and had the same thoughts as you.

William Robison

My Feedback: (3)

Uncontaminated castor oil, kept in a sealed container, does not go bad.

Bill.

reyn3545

Saito 150 question...

I have a 150 on a biplane... 18x6 prop, usually turns about 9000 RPM. I switched to a Slimline Pitts muffler because I wanted to install a smoke tank on the plane... the RPM dropped to less than 7000, and the high needle seems to have little effect on the motor until it litterally floods or starves. I put the old canister back on, RPM immediately jumps back to 9000.

I've checked for leaks, used a good automotive RTV silicon hi-temp sealant, all to no avail. I've heard of others crimping the ends, clogging one tube entirely, etc.. I tried completely plugging one of the tubes with a wooden dowel (just for testing)... still less than 7000 RPM.

Is anyone else out there running an inverted Pitts on the 150? I just can't believe it would rob this much power.

w8ye

My Feedback: (16)

Usually four strokes are not very picky about a muffler

RVM

I figured out why I could not get my 82 tuned right. There is an air leak in the regulator somewhere. I called Iron Bay, but of course, no answer, so I called Archie Stafford, who was, the last time I spoke with him, one of the managers for the company. He no longer works for them, but still was happy to help and told me to call anytime if I needed anything else. Very friendly person. How is that for customer service? [X(]

Anyway, there is air in the lines between the regulator and the valve, and nowhere else in my system. Archie said it could be one or more of three things: the backplate isn't tight enough, the gasket sealing the backplate is torn, or the Schrader valve within the inlet nipple is loose. The first two are easy enough - tighten it, if that doesn't work, go buy a new Walbro gasket. He said to tighten the Schrader valve, I'd need a special tool. Anyone know what this is called, specifically?

I figure all this air in the line is what was causing me to be unable to really make it very rich, or very lean, and why I was off almost 1000 RPM from where it was on the bench. I realy I wasn't running the engine overlean since I had a lot of bubbles in the line. There was a nice smoke trail on the two flights, and spitting raw fuel for almost all of the ground running, so I guess I should be ok. Anything I should to make sure there is no permanent damage to the engine?

RVM

Oh, and where would I get a gasket for a Walbro carb? Sears? I've never really done anything with small engines before besides our glow engines. [sm=confused.gif]

rajul

My Feedback: (58)

I am not sure if the IB is the same size as the Cline, but you could try the D10-WAT Walbro kit. You can get it from through the famous auction site, or google it to find at least a couple other places. Keep the diaphragm in case you have a Cline reg in the future.

TimC

The local NAPA store had a book from Walbro with real size drawings of the parts. I was able to match up exactly a diaphragm I needed.

RVM

Cool I will probably go buy the gaskets and stuff whether I need them or not. I'm sure eventually they will prove useful.

I checked all the fittings on the regulator and the nipple from the regulator the carb was mucho loose. A wrench and a bunch of turns later and it is now very tight.