Rudolph Hart

When i have to listen to an annoying smelly two stroke gasser it's attached to the end of my whipper snipper/lawn edger.You might not believe this but the brand is 'pope' i kid you not,good quality over here.

I liked your comments on the 80 i have never run one,how do you think they compare to the newer 82 ? is there a real advantage in having an 82 up front for all practical flying reasons,i don't mean just the raw specs.

Had my edge 540 tied down out the front of the shed late afternoon.The fg57 twin does not smell good (compared to running the 182 twin on caster and nitro) but when you throttle it up and down quickly it sounds like the next door neighbours rottweiler going off it's head barking..which it does when i do and engine run,that's a win win

Hobbsy

My Feedback: (102)

Here are the .80 and the .82 side by side, the .82 is nearly as powerful as the .91. and weghs less than the .80.

slamn sammy

No Fun!

Charley

My Feedback: (2)

Gosh, I thought this was a Saito thread; not a Saito alky thread.


CR

Cougar429

My Feedback: (3)

After 2 decades as an auto mechanic with my own business for 10 of them, (including a decade of prototype work on natural gas and propane alternate fuel installations) I think I have some background into internal combustion. Same went for the next career, that as a heli-fixed wing pilot/AME with experience in I/C and turbine.

From that, I can estimate that glow and gas engines would require different specs in critical areas. First, their combustion qualities would be significantly different, with combustion temps, pressures and timing requirements unique to each. I would feel confident converting a nitro glow to nitro ignition, but not straight gas ignition without replacing the connecting rod lower end to primarily a roller or at least phosphor bronze. Both Saito 91's have the con rod alloy used as a bearing surface to the crank pin and do NOT seem to tolerate adverse conditions. Doubt they would survive the swap.

When running gas, the spark can be externally controlled and mixture leaned accordingly. Unfortunately this usually results in increased combustion temps, (and also NOx, but doubt we will require catalytic convertors at this point). This would seem to be confirmed if the fact the FG series has improved cooling is correct.

Not sure where the term gasoline is "Oilier" than methanol came from. If that were true, you should be able to run a rich mixture without the risk of washing lubricant away from the cylinder wall/ring interface. As with full size aircraft engines, the break in recommendations from Lycoming and Continental specify straight non-AD, (Ashless Dispersant) mineral oil until consumption stabilizes, (meaning the rings have seated) then allow synthetic or semi to be used. Even though not scientifically valid,this has been the standard practice for years. Basically any non-synthetic oil should be fine to allow the rings to seat. The key is to avoid any synthetic component oils until that break in period is complete.

That does not appear to be the case with our methanol/nitro procedures, unless full-synthetic would require longer break in times. As I never ran full synthetic cannot say. Anyone else have some insight?

As for reliability, I repeat that any engine manufacturer that survives and thrives only making 4-strokes speaks for itself. However, I would choose Saito over any other engine I've tried so far. Having said that, there are others with extremely good ratings as well. Not going to start arguments over specifics, but I have had a few makes across my rebuild bench and they would not be worth even a give-away price to me.

pnmiv01

I have an Saito 100 in my Hanger 9 Miss America P-51. I have the breather nipple attached to the fuel tank vent line with a tee valve just before it connects to the muffler. The engine runs great in this configuration and there is no oil on the bottom of the plane after a flight. Is there any problem with this setup? Will it cause any damage to the engine?

Cougar429

My Feedback: (3)

The purpose of the vent is to allow contaminants and used lubricant that make it past the ring to escape, as well as allowing the case to equalize as the piston moves up and down, (varying the internal volume). You want that to be as short and/or as large a diameter as possible to prevent negative pressure from drawing them back in. By tying that into the muffler vent line you are pressurizing the case with the same source as what aids in fuel feed to the carb. This would prevent good scavenge. If you use fuel running out the muffler to indicate when the tank is topped up during fueling a good slug of fuel can then make it back into the case.

As the engine is running the vent is pretty active and physical aeration by the crank and piston movement can mix those contaminants with the lube oil to be carried out the vent. If this is restricted in any way more of that will remain within the case. From what I've seen it starts to do its nasty work once the engine is idle. Some of those contaminants, such as residual unburnt fuel, combine with water vapor, (also a byproduct of combustion as well as what is drawn back in the vent as the engine cools and changes with environment) to create corrosive chemicals that go after anything ferrous inside the engine. The victims are the crank and cam, piston pin and valve train. Especially vulnerable are the bearings, as any damage to their surfaces can quickly start further failure, along with the particles now able to inflict damage to other components. Better quality bearings are more resistant, with stainless being the least vulnerable next to ceramic, but any metal bearing can be attacked by these corrosives.

I would say that if you want to keep vent outflow from adhering to the fuselage, install a good diameter line long enough to do the job. I've included a couple of pics that best illustrate what I've described. To get the vent clear of the large cowl on Rare Bear, the Saito 125 has a short piece of soft silicone tube fit to the back of the case and a larger diameter plastic line. This has roughly twice the ID of typical fuel line, but the silicone tube is pliable enough to expand to fit.

ps. I have been using plastic tube for all my fuel/vent runs for years. By slowly heating the tube you can bend it to whatever you need with little alteration of diameter, (takes a bit of practice). Unlike brass, this also remains flexible enough to allow for removal of the tank or other components. In many cases the third line is the fill/defuel line formed to follow the inside of the tank to the lower left corner. This does not interfere with the clunk operation at all and allows for complete emptying when done for the day.

pnmiv01

Thanks for the reply Cougar. I will try and copy you vent line approach. Thanks again.

Rudolph Hart

Well there goes me doing something backwards again.That's a very nice installation and very neat.The way i read your post i thought you were going up in id size for the vent line.Where your vent line is routed thru the engine mount and fuse i use a large bore aluminium tube glued in place and a short piece of fuel tube off the crankcase vent which is just pushed an inch or so into the larger aluminium fixed tube.Carries castor well away from the engine and seems to work fine,maybe that's why i don't mind castor.

Hobbsy

My Feedback: (102)

This the way I do it with the TurboHeader on the 1.50

hsukaria

That's neat!!

captinjohn

In that photo, what is that metal part with red on the end. Also is that a adjustable air pressure screw by the fuel line? Just wondering !

Cougar429

My Feedback: (3)

Old Fart, your idea is another elegant solution and one that may be useful in the future. Sounds remarkably similar to what a lot of aircraft used back in the days of the large, honking radials where exhaust velocity was used to aid in drawing cooling air out the cowl.

It may not be evident from the pic, but as stated the ID of the vent line in that app is slightly more than twice that of what I use for the rest of the fuel system. Don't have any pics of the rest as they use a black plastic of even larger ID.

As for the fuel line, that comes via our local hydraulic supplier and is most commonly used for instrumentation runs. It has the same OD and ID as the stock brass tubing supplied with the tanks. To be honest, one day back in the 80's I was eying the air tubing we used for our aquarium and after trying it out asked for more of the same.

FNQFLYER

Is AUD200 to much for a slightly used Saito 150???

Rudolph Hart

Cap that's dave's el flasho engine test bench,neat eh? and did you notice it's not clamped down? very unsafe i always thought the throttle with red dot on top reminded me of those old boxes of 'redhead' matches you buy for settin fire to things that go whizz bang.

Cougar as you know the most common fault saito's seem to have is that people don't like wiping the plane down after,exhaust and vent line residue,i hate it myself.

Fnq you can buy a slightly used fa150 for 200aud ? sounds like a scam to me.Give me the sellers contact details and i'll make sure you don't get ripped off ok?

Hobbsy

My Feedback: (102)

Pate,, Cap and H-man, here it is bolted down with 4" long .25"x20 screws. The visible 6x32 screw is for the throttle rod, I turn the throttle lever, (with the red cap) upside down for the 1.50, as you can see the throttle lever on the engine is quite high. In this picture the engine is one of my favorites, an Irvine Q-.72.

slamn sammy

Hay there OldFart! l don't think l never answered your Q, about my spell check? Hope you where not poking at me? I have a I-Pad, a Tablet and we just not to long ago got a new PC. The PC is the new tech and l do go just to trun it on?? I use the I pad most of the time and the spell Ck, On the l-Pad, if you think you mis-spelled something, you just tuch the woard and the correct spelling (most of the time) will come up. The tablet will correct it in automatically. Oh Ya, Go Satio!! LOL. stay cool

FNQFLYER

Old Fart, do you think our newly installed CFI would rip me off. I'll e mail you with updates re the Nationals if you wish but at this point the QLD nats will be in part held at West Wylong and Canowindra and it means I can first the first time in 20 years compete in scale. To that end I traded a 30* year old partially completed Byron Beech Baron for a Lazor 70 and it might appear as if the Saito (virtually NIB, eat your heart out) will come my way via another trade.

FNQFLYER

Cougar dare I say it is good to see another aviation person who likes round engines etc and has the time and scars to prove his time in "service" in the industry on this site. Me, I have been in the game since 1966 and despite approaching official old age it looks like I will still be involved as much as I want for as long as I want and am able to do so.

Rudolph Hart

Sammy all good did you get your new saito engine off your brother yet?

Trev some pix of saito/fourstroke powered a/c from the nats by email would be good mate.
ps the other next door neighbours tomcat has just jumped the fence and is eating a huge bowl of catfood i just put out.

slamn sammy

No, he has not sent it to my yet. He's saying that he's coming up here? l would reather go down there! That was l can leave on my terms! (We don't get along that well) I'll holler when l get it.

aggieman

HOBBSY, after break in of your Saito's do you continue to use the wildcat premium xtra?

hsukaria

Love those Irvines! I have a couple of old 40 ABC (glow) that are about 20 years old. One has been running forever, and the other barely broken in.
Throttle response is excellent, can run a wide range of props, and not finicky on fuel. When the fuel gets too old to use on the other engines, I run it through the Irvines, they don't have a problem with it.

FNQFLYER

Old Fart, you should come over to Brisbane for the Nats, just after easter and if you are doing a road trip on the way stop in at Canowindra for easter. You can do as I do and take a run around Bathurst just for fun (not much good since they put that kink in conrod straight. (For the American cousind figure out why they called it that)
On Irvines (and Supre Tigres) I have tuned mufflers (stingers) for the 21, 25 and 46. They are great engines cause they use FAI fuel (4:1 Methanol to castor) and go like the clappers. My Supre Tigres all have Tiger Paw mufflers (or versions of the same) and also go well. 19000rpm out of a G500 (40 size) with an 11x6 Bolly carbon prop. Good stuff and those are the targets for the 4 strokes. Already have one in site but not in hand, an OS 26 (4S) for R/C cars according to the specs 20,000 plus. And yes Old Fart it is priced at $200 more on it later

Rudolph Hart

I think this is all dave's fault..he 's the one that mentioned irvines,look at the chaos now! pretty soon i'll be in the manure as well,i just kidding dave.

Seriously,as i understand it hobbsy likes to stay on thread with a little bit of harley thrown in no offence intended dave.Blw will let you stretch the envelope a bit from time to time if it's all friendly,as it should be,and not overly long.

Trevor brings a good point back up on rpm limits for our fourstroke saito's.A while back i was reading my saito 30 manual and attached was an ad for the same engine in 'sc' and saito advertised that this engine would freely rev well over the 20k mark.Now trevor says that os have a 26 that will do the same..what are we missing out on here? if you would like to run something small very fast with a fourstroke like my saito 30 which won't reach 12k no matter how much nitro you throw at it ?