stevesak

My Feedback: (27)

OK.... since everyone seems to be getting their engines from Hobby King, I am now comfortable that their Seidel business is indeed legit..... With 4 left in stock, I finally pulled then trigger on the ST-990. Just bought it.

Just out of curiosity, with all the talk about corrosion in the Seidels, ant the cause being nitro leftovers not being flushed out.....

Doesn't Seidel recommend NO NITRO in the fuel oil mix? I thought I recalled some info in this thread from several years back about sourcing pure methanol for folks Seidels. Just add oil?

That would mean no nitro, and no corrosion, right? Of course after-run is always a good idea.

So if I'm not crazy (for that anyway) and no nitro is needed on the German engines, is then same true for the Indian Seidels too?

On another note, I sure would like to get my hands on one of the ST-735 engines, but HK doesn't carry them yet and the UMS folks exchange rates are from way back when the dollar was weak. to buy one today, our European friends are only paying Eur945 (equivalent to $1183), but they want $1,417 from us folks in the US. It sounds like they are still of the mindset that the exchange rate is 1:1.60 instead of then actual 1:1.25 that it is today. I guess that Ill wait on that one...

wheels

Thanks for that super puma, perhaps that's what happened here. Now I have to decide if I want to just send it away or open it up first. Does anyone know of online references for working on the three cyl. saitos?

Kmot

My Feedback: (24)

Steve, I do not think the nitromethane is the cause of rust. It is the methanol, I have come to understand. Because methanol is hygroscopic, and that means it absorbs moisture from the air. Left inside an engine, it attracts water which in turn rusts steel. Something like that. Here is an interesting article gleaned from the internet:

Many people use after run oil in their engines after they are finished running it to prevent rust but it is not necessary if you use a good quality fuel. Nitro fuel is made up of three main components...

Nitromethane
Methanol
Oil

The nitromethane portion of rc nitro fuel is actually not overly hygroscopic, which is the term for a subsctance that readily attracts and retains water. The hygroscopic portion of nitro fuel is the methanol rather than the nitro.

Some people confuse nitromethane with nitroethane which isn't used in most nitro r/c fuels. Nitro ethane is highly hygroscopic.

Rust in nitro engines is caused by water moisture drawn in from the air by the hygroscopic methanol in the fuel and accelerated by any residual acids left in the engine. Cheaper methanol has residual acids in its natural state that greatly enhance rust. Good quality fuels use good high grade methanol with very low acid contents.

The second source of residual acids is from partially burned fuel. This is the most common source of the acids which together with the moisture can cause the crankshaft and bearings to rust.

Most people think you should run an engine dry after you run it but I strongly advocate against this for the reason mentioned above. It leaves more half-burned fuel in the engine than otherwise. Also running the engine bone dry puts undue stress on the engine parts up until it runs completely out and is just as bad as running the engine too lean. And if you use a good quality fuel with the lubrication properties of a good oil package, then you will actually experience less rust than if you burned all of the fuel out and let the engine sit.

davidgeorge212

Now Im curious to see how well the moki 150 works for you and the beast. I am very interested in seeing how you are going to mount it and how well it will fly the beast. I just happend to pick The beast up myself just the other day and eventually I will get a motor for it. So keep us informed of how things go and tell us what you had to do to mount it to the firewall and make it balance.

If I dont go with a moki, I will probably just stick with a DA-100. I am really not into the "3D" type flying and will more than likely only fly this plane in a scale like manner. I hope the moki works out for you, and if it does I hope to get the same setup.

Below are pictures of my Beast. I am increadably surpised at how little time it takes to put this plane together.

Thanks,

Maxam

My Feedback: (62)

DadR, I ran the engine on conventional fuel for a few tankfulls. While the engine was running I sprayed the rockers with WD-40 to flush out the wear metal. I use Campbell-Housefield air tool oil for after run into the carb and I simply inject the same through a cam follower hole on top of the engine. I do need to do a valve adjustment, which is not a big deal. I have found that this is not critical.

wheels

Tore my saito apart today with a friend of mine who's infinitely more mechanically inclined than me, what did we find? .......................... RUST. and TONS of it. Luckily the cylinders and pistons seem ok. The rear bearing is shot and will be replaced, the front is ok but it's going to be replaced as well just for the warm fuzzy feeling it will give me knowing that the bearings in my motor are new. The timing gears, and crank were covered in rust, and have been hand polished to the point that the spots that are supposed to be shiny are shiny, and the spots that aren't supposed to be shiney aren't caked with rust.

To be honest, beyond that it doesn't seem like there is much of anything wrong with the motor. The parts are ordered to reassemble.

Our only lingering concern is the con rod pins (bottom ones, not the wrist pins), they are a little rough and the holes through wich they pass have smears of what looks like brass in them. Horizon does not list the lower con rod pins on their site so as of now I have no replacements for them coming. Does anyone have any input as to wether this might be normal? Or where I might find replacement pins?

super puma

My Feedback: (6)

Tom
I think you are right about methanol drawing water out of the air, we fly on the ice at our lake, and sometimes find the fuel filter clogging due to ice crystals.
My friends used to leave the fuel can outside in below freesing, then strain the fuel, it was amasing how much ice crystals left in the strainer filter.
I have heard that even in a sealed container methanol can draw moisture over the years. This of course will corode an engine if left inside over time.
BT......................

S.L.engines

Tom is absolutely right because that's why we're leaving Glow engines and we have them cercandi gasoline. The gas does not oxidize and corrode if it is already lubricant. And not igriscopica comeil methanol.

This is what happens too many engines in my old Costalletion if you use synthetic oil and castor andnot above 5% nitromethane.

S.L.engines

[

S.L.engines

All this after only 3 hours of operation and without leaving a day !!!!!!!!!!!

S.L.engines

The engine when used with castor oil and very good with up to 5% of nitrometnao must always remain so .....

S.L.engines

The engine when used with castor oil and very good with up to 5% of nitrometnao must always remain so .....

kochj

Well the Wildcat (same as ys fuel) must be crap, because I had rust started in my saito 325 (tiny bit) after running
mine and filling it up with compressor oil...

Perhaps, becuase I didn't use a electric starter at the end to spin out any remaining fuel (ran it till it wound't run anymore)

I hate the effects of glow fuel on engines...
I will have to get these planes up and run the crap out of the engines...

How many can bet the OS 7-cyl radial engine runs like a clock...??

kochj

Still can't figure out why OS didn't make there newest radial Gasoline???

Wulf

My Feedback: (5)

Use caster fuel-I`ve never had a problem in the 10 years I`ve been using caster.

Dad_Roman

Is that a fully synthetic or is there some castor in it?

skipb

My Feedback: (6)

The wildcat fuel is totally synthetic, YS engines can not tolerate castor or petroleum based lubricants.

Skipb

Wulf

My Feedback: (5)

I just looked up manual for the YS- FZ110 and it says , synthetic OR caster can be used or a combo of both as long as lube content is 15-20%

Dad_Roman

While I dont want to get into the YS can/cannot argument....


I do want to restate (in simple terms)

For an operating engine, synthetics have magnificent shear qualities for protection.

Castor is also good having almost the shear qualities of synthetic.

For an engine that is sitting DORMANT, the "wetting" or "break free" qualities of your oil are what protect it from rust.

Castor has top notch qualities in this regard IE:20-30 year old engines being loosened up and ran.

Synthetic has almost NO wetting qualities which is why our little engines develop rust so quickly. When an engine with synthetic in it stops, envision that the oil sheets off the components like they were waxed.

I read a great thread written by a lubrication engineer about this subject....lost the link, sorry

Wulf

My Feedback: (5)

I would think then a mixture of synthetic and caster would be the best of both worlds for glow engines.I love pure synthetics in gas engines however the glow engines with their affinity for moisture fuels seem to need the caster for it`s rust preventive qualities.

SOUTHERNX

Type www.go-cl-se/castor.html into your search engine, there is some info here re. glow engine lubrication,Mark.

wheels

NM

kochj

I have been even added some premium castor (sig I believe) to my Wildcat fuel.. 15% nitro 18% syn. and add a 2-3 shots of castor
If you buy the wildcat premium, you have 18% SYn/castor mixed already.

I am sure tha due to the engine not being spum with a starter after ALL the fuel is being run
out (wouldn't start anymore) and adding the after run oil. is the culprit..

I will have to pick up a good starter.
My sylavan HD isn't enough....
Might pick up a MAgnum Geared....50$ not bad, and will start a 1.80 size...

Kmot

My Feedback: (24)

My Magnum geared starter cranks over my FS400 radial pretty good too.

kochj

good to hear.