Saito 82 surging at wot
#26
Reed..yeh i get it,cool dude nice music.Apoligies wc.
Goose awesome job man,took me ages to get that o ring out and even harder to put the first one back in,lucky i had 2 spares.
Goose awesome job man,took me ages to get that o ring out and even harder to put the first one back in,lucky i had 2 spares.
#27
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13x6 is too small for an 82. I have a Saito 65, APC 13x6 is perfect for the 4*40 it is mounted on. I also have the Saito 82 turning an APC14x6, perfect combo for the 3D profile plane behind it.
My 82 needed to be run real rich on high end for about a full gallon. As it runs in, you will be able to lean out the low end screw and retain good throttle response. Adjust low speed in about 1/16 turn increments.
Good luck, MikeB
My 82 needed to be run real rich on high end for about a full gallon. As it runs in, you will be able to lean out the low end screw and retain good throttle response. Adjust low speed in about 1/16 turn increments.
Good luck, MikeB
#28
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Bear with me guys, sorry for the delay. I have the seal kit i just haven't had time to work on the engine. This year has been crazy. we have worked more overtime this year than the last couple years combined. The Senior Kadet has taken most of the year to build. I will have some time soon to get back on it. My son and I have been flying some scratch built 400 size 3 channel planes in the mean time and loving every minute of it. I will post pics of the Kadet as soon as my daughter is done with the camera for a science fair project. Thanks again everyone.
#29
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Several things I missed. One the Low Speed Needle (LSN) has no impact on WOT. The High Speed Needle valve controls all the fuel flow into the carb (hence engine). The LSN impacts fuel flow into the engine from idle to mid range. So whether the LSN is rich or not is unimportant in this case.
I would not use a wooden propeller, four strokes need the extra weight of the composite (nylon/fiber glass) propellers. And a 13 X 6 sounds to be to small of a prop. My understanding is the new modern Saito .82 has the muscle of the old .91s. If that is the case, you should be using a 13 X 8 as a minimum prop.
And like the others 9,000 RPM is decent for a new engine. Less than a gallon of fuel through the engine is not enough for a good break in. More like a gallon and half would be closer.
As regards the O-ring on the head, I have seen folks use a plastic tie wrap around the engine head tightened down to force the intake manifold hard up against the 0-ring. That is not pretty but it works.
And finally take a look at the fuel tank. Surging at max is often indicating that the fuel flow is not up to speed. Since you have been through the carb, check the tank for restrictions.
Good luck!
I would not use a wooden propeller, four strokes need the extra weight of the composite (nylon/fiber glass) propellers. And a 13 X 6 sounds to be to small of a prop. My understanding is the new modern Saito .82 has the muscle of the old .91s. If that is the case, you should be using a 13 X 8 as a minimum prop.
And like the others 9,000 RPM is decent for a new engine. Less than a gallon of fuel through the engine is not enough for a good break in. More like a gallon and half would be closer.
As regards the O-ring on the head, I have seen folks use a plastic tie wrap around the engine head tightened down to force the intake manifold hard up against the 0-ring. That is not pretty but it works.
And finally take a look at the fuel tank. Surging at max is often indicating that the fuel flow is not up to speed. Since you have been through the carb, check the tank for restrictions.
Good luck!
#30
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The manifold leaking problem is a FA-72 issue only, even when the parts are pretty much the same in places. And, there's other fixes the work better and look better than plastic ties. I got a metal backplate from a hobby shop in England for mine. Backplate combined with cheaper shipping costs came out even with what you would pay in the U.S. But, to repeat it, the 82 does not have backplate issues like the 72. If you don't order a metal backplate for a 72 that becoming impossible to run then swab some epoxy in the backplate screw threads, let dry, and screw on the backplate. That will solve it and the screws will back out easy enough. You can reuse that initial application of epoxy a few times.
WC, the low speed has a major impact on how the engine runs and what goes on with the HS needle. In fact, the low speed is your most important adjustment on a Saito and you should base everything around it being adjusted right.
Here's something easy to do and will be very interesting to watch. Set your high speed needle as smoking rich as you can. Make sure your low speed needle is lean enough to not smoke hardly any. Now run the engine and watch the exhaust as you inch up the throttle towards wide open. The engine won't begin to smoke at all until you are real close to wide open if you adjusted the low speed lean enough. That's when the high speed begins to work- about 75 to 85 percent throttle and you can see it.
I know some people have all kinds of reactions to my epoxy advice, but it works. It is a good cure for the threaded muffler bolts on 2 strokes that attach the muffler to the engine. The ones that always vibrate loose in the air.
WC, the low speed has a major impact on how the engine runs and what goes on with the HS needle. In fact, the low speed is your most important adjustment on a Saito and you should base everything around it being adjusted right.
Here's something easy to do and will be very interesting to watch. Set your high speed needle as smoking rich as you can. Make sure your low speed needle is lean enough to not smoke hardly any. Now run the engine and watch the exhaust as you inch up the throttle towards wide open. The engine won't begin to smoke at all until you are real close to wide open if you adjusted the low speed lean enough. That's when the high speed begins to work- about 75 to 85 percent throttle and you can see it.
I know some people have all kinds of reactions to my epoxy advice, but it works. It is a good cure for the threaded muffler bolts on 2 strokes that attach the muffler to the engine. The ones that always vibrate loose in the air.
Last edited by blw; 11-26-2014 at 08:42 AM.
#31
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Good advice. The cost of a tie wrap, I'm guessing, less than a nickel. Cheap fix. I have seen others use CA but that was on wood, more specifically balsa. But the epoxy is a great idea. Epoxy is, however, heat sensitive. The higher the heat, the weaker the epoxy. Of course, you could use JB Weld which is epoxy based and has good temperature characteristics.
Let's all hope Gu Malzahn has a good day in the Iron Bowl. Geaux Tigers!
Let's all hope Gu Malzahn has a good day in the Iron Bowl. Geaux Tigers!
#33
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Barry's post is a good one, now, if you happen to get the LS needle too lean the HS needle will no longer allow the engine to go rich. In fact, it will most likely just quit when you go past the 75 to 85% mark Barry mentioned. The LS needle has a lot to do with Saitos being shaky, if Barry mentioned that I apologize.
#34
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Merry Christmas everyone. Sorry it took so long to come back with a response. I finally had time to install the seal kit and fire up the engine today. The best Christmas present ever. the engine ran flawlessly. I was turning over 10,000 rpm with no surging problems. it idles great. I tuned it out enough to install on the Kadet. This engine runs like a champ. The vibration issues are almost non existent. This engine is great. It has never ran so good since I've had it. Thank you everyone with the great advise. I can hardly wait to get this thing airborne. My wife thinks I'm crazy for jumping around with joy after I ran a tank through it and had no issues what so ever. Thanks again and Merry Christmas.