Glow head brotherhood.
04-29-2017, 05:10 AM
#1427
Cheese castings sound yummy. The Uctkam castings have lots of sand mixed in, and the screws get ruined. If you try to retap them, then your tap is ruined. The factory must go through a lot of taps. Oh well, that is what helicoils are made for. There are locking ones too. One thread of the spring has a dimple pressed in.
04-30-2017, 06:35 PM
#1431
I use antiseize on the head bolts, and glow plug threads. Not always on the backplate if they are plastic. I have used red locktite on baby bee needle valves that were loose. Clean the female thread with acetone, and oil or wax the needle. Just use a toothpick dab on the needle so it does not clog the hole.
05-01-2017, 02:35 AM
#1432
My Feedback: (2)
Red Loctite is the high strength stuff. I don't think that it's meant to be used on fasteners as small as the ones used in our engines. I thought that I had heard a friend mention that it had to be heated to 400F to soften it enough to loosen.
If I remember correctly from years ago, 'purple' Loctite (aka Loctite 222) was a removable Loctite for fasteners that were under 1/4" but the 222 can be a bit hard to find. Try Amazon, McMaster-Carr (www.mcmaster.com) or eBay. Loctite 242 was the removable Loctite for fasteners over 1/4". I think that Red Loctite is supposed to be non-removable, and is made for larger fasteners. Can anyone out there verify if I am remembering this correctly?
I also found this if it is of any help to anyone, including how to work with red Loctite.
The Difference Between Red, Blue, Green and Purple Threadlockers - Henkel Adhesive Technologies Blog
Just my $.02
Bob
If I remember correctly from years ago, 'purple' Loctite (aka Loctite 222) was a removable Loctite for fasteners that were under 1/4" but the 222 can be a bit hard to find. Try Amazon, McMaster-Carr (www.mcmaster.com) or eBay. Loctite 242 was the removable Loctite for fasteners over 1/4". I think that Red Loctite is supposed to be non-removable, and is made for larger fasteners. Can anyone out there verify if I am remembering this correctly?
I also found this if it is of any help to anyone, including how to work with red Loctite.
The Difference Between Red, Blue, Green and Purple Threadlockers - Henkel Adhesive Technologies Blog
Just my $.02
Bob
05-01-2017, 04:05 AM
#1433
My Feedback: (102)
Join Date: Dec 2001
Location: Colonial Beach, VA
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I do not use anything on the engine bolts except Corrosion X which I also use as ARO. I used blue Loctite on a Saito exhaust pipe once and when I removed the pipe to replace it with the later straight pipe and cast muffler part of the threads came out. The exhaust port looked like a snaggle tooth shark. Teflon plumbers tape is the best.
05-01-2017, 09:33 AM
#1434
I would never use thread locker of any kind on any fastener on a model engine. If head screws come loose on a regular basis, either the engine is running too hot (lean), the fasteners are damaged, or not tight enough from the get go. Some folks have had good luck snugging screws down with the engine warmed up.
06-04-2017, 03:03 PM
#1438
Join Date: Nov 2006
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Moki . Com. Engine company in Hungary
the radial engines are German made not real moki, most people don't know that
was out flying today with my tiger 2 , now I'm home setting hi and lo needles on this beast , next Sunday the maiden us 1000.
stoner
the radial engines are German made not real moki, most people don't know that
was out flying today with my tiger 2 , now I'm home setting hi and lo needles on this beast , next Sunday the maiden us 1000.
stoner
07-12-2018, 07:26 PM
#1440
I have just picked up and old Super Tigre .90 and was told not to use it because the older .90 had the crank from a .75 and it was unbalanced and would cause terrible vibration. Has anyone here ever heard of this? If this is true if I can find a crank will I need to replace the rod as well?
Thank you,
Mike
Thank you,
Mike
07-12-2018, 10:12 PM
#1441
Join Date: Oct 2004
Location: Istanbul, TURKEY
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I have just picked up and old Super Tigre .90 and was told not to use it because the older .90 had the crank from a .75 and it was unbalanced and would cause terrible vibration. Has anyone here ever heard of this? If this is true if I can find a crank will I need to replace the rod as well?
Thank you,
Mike
Thank you,
Mike
07-13-2018, 01:47 AM
#1443
I do not use anything on the engine bolts except Corrosion X which I also use as ARO. I used blue Loctite on a Saito exhaust pipe once and when I removed the pipe to replace it with the later straight pipe and cast muffler part of the threads came out. The exhaust port looked like a snaggle tooth shark. Teflon plumbers tape is the best.
On exhaust threads I have tried just about everything and had used Teflon tape for many years. It worked well. A few years ago I came across "SWAK" brand sealant. SWAK is an anaerobic thread sealant paste that contains Teflon. It flat out works perfect for this application. Being a paste, it flows into and fills all the voids. It does not shred . The anaerobic action helps lock things in place yet it is readily disassembled and never siezes or erodes threads as Loctite can. The SWAK is made for high temps and handles the exhaust heat with ease.
SWAK is only available from industrial suppliers, you won't likely find it at Podunk Hardware. It is a bit pricey but a little goes a long way. A few guys could pitch in and share a single tube for a lifetime.
My tube has done all of my engines, many other engines at our field, including some "problem" engines, I have even sent out several samples to folks in the various user groups. Still hav plenty left over.
Last edited by Jesse Open; 07-13-2018 at 01:57 AM.
07-13-2018, 03:03 AM
#1444
I have just picked up and old Super Tigre .90 and was told not to use it because the older .90 had the crank from a .75 and it was unbalanced and would cause terrible vibration. Has anyone here ever heard of this? If this is true if I can find a crank will I need to replace the rod as well?
Thank you,
Mike
Thank you,
Mike
07-13-2018, 04:59 AM
#1445
AFAIK, the .75 and .90 use different cranks. Even if they are the same, there should be no issues with it. I run a SuperTigre S90K on a tuned muffler well above the rpm most people would run them at and I have no worse vibrations from it than I’d have with any other engine. Balance your prop and hub and that’s as good as it needs to be.
I knew I couldn't be the only Super Tigre user on RCU. I will admit I do have a bet peeve about guys who buy a new engine and throw the box and instructions away the minute they get it home and don't keep all the parts together. My other pet peeve is guys who do the same to new servos. They always manage to lose the the screws and arms b y taking them off and putting them elsewhere. I buy into the idea the manufacturer knows best on how to break in a new engine and different brands/engines do have different break in routines. I have bought my share of nearly new engines that weren't running well that were fixed by following the instruction sheet for break in.
07-13-2018, 06:16 AM
#1446
I don't have the .90, but a guy in the club does, and had a lot of trouble. The muffler was vibrating off, and he had trouble deadsticking nearly every flight. Not sure if it was the shaking or a tuning thing. At any rate, maybe a bit of dremelling inside the piston, or milling a slot in the crank counterweight and filling it with solder would help, if it is a problem. You could get a header and pipe or something different from the stock muffler to solve that problem too since there is no muffler anyway. Funny, the guy said he tossed that motor, but he really didn't. I was going to offer him pretty much nothing for it, but I really have no use for it.
07-13-2018, 06:29 AM
#1448
I didn't get too involved with it because he seemed to be in a pretty volatile mood every time he ran it. He has an Evo on it now and still has some problems with that too, but not as much. So no gasket is the answer then? I do have a ST .75 kicking around with no gasket and the flanges are a bit rough. I could mill them flat.
07-13-2018, 07:55 AM
#1449
Don’t use a paper gasket. If the muffler flange leaks (which many do), clean the mating surfaces and use a thin film of sensor safe RTV silicone. This works great for me.
The guys who who have trouble setting SuperTigre carbs often don’t read the instructions on how to set them. They aren’t adjusted wholly like a standard 2-needle carb. Set the high speed for about 400rpm rich from peak and set the low speed needle for a good low reliable idle. Adjust the spraybar to adjust the midrange. Often the midrange is rich, so adjusting the spraybar so the fuel inlet nipple points down a little bit does the trick. Move it in small increments - it’s easy to miss the “sweet spot”. Also, I’ve found that if they’re going to run rich in the midrange, it’s usually for the first 2-3 gallons of fuel. Often after they’re well broken in and the ring is seated, they may run lean in the midrange requiring moving the spraybar back to the factory position (cats eye facing directly towards you as you look at the bottom of the carb) of “straight in” or close to it.
I love ST carbs. I find them to operate fantastically.
The guys who who have trouble setting SuperTigre carbs often don’t read the instructions on how to set them. They aren’t adjusted wholly like a standard 2-needle carb. Set the high speed for about 400rpm rich from peak and set the low speed needle for a good low reliable idle. Adjust the spraybar to adjust the midrange. Often the midrange is rich, so adjusting the spraybar so the fuel inlet nipple points down a little bit does the trick. Move it in small increments - it’s easy to miss the “sweet spot”. Also, I’ve found that if they’re going to run rich in the midrange, it’s usually for the first 2-3 gallons of fuel. Often after they’re well broken in and the ring is seated, they may run lean in the midrange requiring moving the spraybar back to the factory position (cats eye facing directly towards you as you look at the bottom of the carb) of “straight in” or close to it.
I love ST carbs. I find them to operate fantastically.