YS 60FS Tuning Help Needed
06-03-2013, 07:40 PM
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YS 60FS Tuning Help Needed
I have a used YS 60FS I bought recently. I'm trying to set it up with a muffler to use in my next SPA plane, a Bluejay Dirty Birdy. I fitted it with an OS744 muffler from my spare 61 FSR with only minor modifications per a recommendation I received earlier. A test run today showed a solid 12,810 static rpm with an APC 11-7 & 10% Cool Power. The OS muffler has a slight necking-down inside the forward end of the exhaust outlet. I'd estimate it's no more than 0.020" to 0.030". Would it gain me anything to clean that up to match the diameter of the remainder of the outlet?
Now to the real problem I'm having - setting the idle mixture. I can set the idle mixture on a non-pressurized engine like an OS or Super Tigre with the best of them, but this YS has me going in circles. I'm having a very hard time telling if it's too rich or too lean. It's been a lot of years since I adjusted an YS 2-stroke and I just can't tell which way I need to go.
The regulator was screwed in - leaned - about 1 to 1 1/4 turn from flush when I received the motor. It has "9/10/89" engraved on the mounting lug, but doesn't appear to have been run much at all. I tried it at that setting but it's wasn't right.Can anyone help me with a good description of the process for adjusting the regulator? Specifically, how does the engine react - andwhat does it sound like[/b]- when it's too rich or too lean and the throttle is opened quickly from idle? The engine currently has an OS #8 glow plug in it - what do you guys prefer? I checked the diaphragm and it appears to be just fine, but I may replace it just to rule it out.
Once I get this thing close, I'm going to install the engine in my trusty old RCM Trainer 60 and fly and tweak it. With the Trainer's open front end, it should make final adjustments easy. I want it dead consistent and reliable before it goes in the new DB.
Thanks, guys!
Now to the real problem I'm having - setting the idle mixture. I can set the idle mixture on a non-pressurized engine like an OS or Super Tigre with the best of them, but this YS has me going in circles. I'm having a very hard time telling if it's too rich or too lean. It's been a lot of years since I adjusted an YS 2-stroke and I just can't tell which way I need to go.
The regulator was screwed in - leaned - about 1 to 1 1/4 turn from flush when I received the motor. It has "9/10/89" engraved on the mounting lug, but doesn't appear to have been run much at all. I tried it at that setting but it's wasn't right.Can anyone help me with a good description of the process for adjusting the regulator? Specifically, how does the engine react - andwhat does it sound like[/b]- when it's too rich or too lean and the throttle is opened quickly from idle? The engine currently has an OS #8 glow plug in it - what do you guys prefer? I checked the diaphragm and it appears to be just fine, but I may replace it just to rule it out.
Once I get this thing close, I'm going to install the engine in my trusty old RCM Trainer 60 and fly and tweak it. With the Trainer's open front end, it should make final adjustments easy. I want it dead consistent and reliable before it goes in the new DB.
Thanks, guys!
06-03-2013, 10:09 PM
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RE: YS 60FS Tuning Help Needed
Hi Jim....
I'm building a BJ BD also....but I am using a NR 60 side exhaust with their muffler.
I'm pretty familiar with the YS....so I would start here....
Set regulator screw to flush with the housing.
Start the engine and set the n/v to right on the money...not rich, not lean.
You can test the high speed mixture by quickly pinching the fuel line at full throt. If it speeds up slightly the n/v is too rich.
Then set the throt to midrange and let it run....
Pretty quick you will be able to determine if the midrange is too rich or lean.
If it speeds up it's too lean....slows down, too rich.
In on the regulator is lean, out is rich.
I would move the regulator 1/4 turn at a time until you get close then 1/8 turn as you sneak up on it.
Adjust the regulator to correct the midrange mixture.
After each regulator adjustment reset the n/v.
Keep repeating that procedure and if the rest of the engine, gaskets etc are in good shape, you'll be able to NASCAR the throttle.
I dont remember what plug I was using but the plug you have should be ok...the K&B 1L should be ok too. For sure the Enya 3 or Hobby Shack performance 3 (Enya 3 clone) will be good.
Dave
I'm building a BJ BD also....but I am using a NR 60 side exhaust with their muffler.
I'm pretty familiar with the YS....so I would start here....
Set regulator screw to flush with the housing.
Start the engine and set the n/v to right on the money...not rich, not lean.
You can test the high speed mixture by quickly pinching the fuel line at full throt. If it speeds up slightly the n/v is too rich.
Then set the throt to midrange and let it run....
Pretty quick you will be able to determine if the midrange is too rich or lean.
If it speeds up it's too lean....slows down, too rich.
In on the regulator is lean, out is rich.
I would move the regulator 1/4 turn at a time until you get close then 1/8 turn as you sneak up on it.
Adjust the regulator to correct the midrange mixture.
After each regulator adjustment reset the n/v.
Keep repeating that procedure and if the rest of the engine, gaskets etc are in good shape, you'll be able to NASCAR the throttle.
I dont remember what plug I was using but the plug you have should be ok...the K&B 1L should be ok too. For sure the Enya 3 or Hobby Shack performance 3 (Enya 3 clone) will be good.
Dave
06-04-2013, 03:03 AM
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RE: YS 60FS Tuning Help Needed
Part of my personal "SOP" on a newly acquired engine is to go through it and just replace all the silicone stuff (diaphragm, carb o-rings ect...)...It may not always be necessary but I do it for my own piece of mind...From that point on **No petroleum based products** as they will wreak havoc on the silicone stuff...I think your a YS guy so you knew that already... 
Regulator screw flush with the housing and I try to forget about it...I consider it the last option strive not to touch it...If I do it's 1/16 or 1/8 turn at a time to smooth out the transition...
If it pauses or hesitates when advancing the throttle that's an indication it's too lean...If it stumbles/gurggles/burbles then it's rich...
If your going through glo plugs is an indication it's too lean as well...
I have always used the OS#8 plug and Powermaster YS 20/20 fuel..
Have Fun...
Chuck.
Regulator screw flush with the housing and I try to forget about it...I consider it the last option strive not to touch it...If I do it's 1/16 or 1/8 turn at a time to smooth out the transition...
If it pauses or hesitates when advancing the throttle that's an indication it's too lean...If it stumbles/gurggles/burbles then it's rich...
If your going through glo plugs is an indication it's too lean as well...
I have always used the OS#8 plug and Powermaster YS 20/20 fuel..
Have Fun...
Chuck.
06-04-2013, 06:21 AM
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RE: YS 60FS Tuning Help Needed
I have always used the OS#8 plug and Powermaster YS 20/20 fuel..
that s it... you need at least 20 per cent nitro.. otherwise, the fuel combuston is not right at low rpm, and the engine goes richer and richer... and stall...
that s it... you need at least 20 per cent nitro.. otherwise, the fuel combuston is not right at low rpm, and the engine goes richer and richer... and stall...
06-04-2013, 10:06 AM
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RE: YS 60FS Tuning Help Needed
Jim,
I have attached the manual for the YS 60 FR which gives the tuning instructions. I have found that these work as long as you follow the instructions carefully. Note that it is really hard to do this "by ear". I have found that the best results are obtained with a good tach - especially for setting the idle.
Jeff
I have attached the manual for the YS 60 FR which gives the tuning instructions. I have found that these work as long as you follow the instructions carefully. Note that it is really hard to do this "by ear". I have found that the best results are obtained with a good tach - especially for setting the idle.
Jeff
06-04-2013, 10:23 AM
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RE: YS 60FS Tuning Help Needed
Thanks, Jeff. Unfortunately, a good tach doesn't help much for deciding which way to adjust the low end mixture. If I'm wrong, please correct me.
I think I'm going to tear it down completely and do a 100% cleaning and replace the diaphragm before I continue. There really isn't any big hurry - the DB won't be done for a while anyway and the plane is already fitted to the YS. I just wish I wasn't such a slow builder.
I think I'm going to tear it down completely and do a 100% cleaning and replace the diaphragm before I continue. There really isn't any big hurry - the DB won't be done for a while anyway and the plane is already fitted to the YS. I just wish I wasn't such a slow builder.
06-04-2013, 12:31 PM
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RE: YS 60FS Tuning Help Needed
Jim,
On the contrary, the tach is a great help for judging when you've got the idle below 2500k. Read the tuning sequence again. And remember that every time you adjust the diaphragm you need to readjust the high end. I tried to tune my YS engines by ear at first, but had little success. Then I broke down and read the instructions. I followed the procedure described there and it worked. Sigh...
On the contrary, the tach is a great help for judging when you've got the idle below 2500k. Read the tuning sequence again. And remember that every time you adjust the diaphragm you need to readjust the high end. I tried to tune my YS engines by ear at first, but had little success. Then I broke down and read the instructions. I followed the procedure described there and it worked. Sigh...
06-04-2013, 01:07 PM
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RE: YS 60FS Tuning Help Needed
I hate it when following the instructions actually results in success, Jeff!
I'll give it a shot according to the directions and see if I get better results. Guess that means rigging up a throttle servo on my test stand.
I'll give it a shot according to the directions and see if I get better results. Guess that means rigging up a throttle servo on my test stand.
06-04-2013, 04:15 PM
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RE: YS 60FS Tuning Help Needed
Jim....nothing wrong with reading the directions but I have better results using the method I described.
It's ok to use a tach but it really is not needed unless the engine is surging a little which is caused by an air leak.
The tach is useful then to determine where the leak is as you squirt alcohol around all the gaskets while it is running.
When the engine goes suddenly rich when you squirt an area....you can see it on the tach and right there is where the engine is sucking air.
As far as setting the idle...who cares what it is....set it to the lowest reliable idle with the transmitter.
As long as you are going to tear it down....pay particular attention to the gasket under the carb and regulator. The fuel transfer holes swell and block the fuel holes causing all kinds of weird problems.
The plunger in the regulator has a silicone valve on one end...make sure this valve outer circumference does not have any flash from the mold or any nicks from the cutter when it was cut off the mold tree.
This has definately been a problem previously....I had 2 engines with this problem.
Also.....the plunger passage through the regulator has been a problem on some engines....machining chips...swarf...have been known to be in the passage causing the plunger to bind and mess up the mixture and cause leaks from the intake when the tank is pressurized.... also you cannot adjust the idle and transition mixture.
Remove the throttle barrel and look at the idle slit in the barrel. This slot collects trash and some engines have had chips in there as well. You can run a razor blade through the slot to make sure it is clean.
Remove the n/v and backflush with alcohol...then blow out.....cleans out any trash.
Have Fun
Dave
It's ok to use a tach but it really is not needed unless the engine is surging a little which is caused by an air leak.
The tach is useful then to determine where the leak is as you squirt alcohol around all the gaskets while it is running.
When the engine goes suddenly rich when you squirt an area....you can see it on the tach and right there is where the engine is sucking air.
As far as setting the idle...who cares what it is....set it to the lowest reliable idle with the transmitter.
As long as you are going to tear it down....pay particular attention to the gasket under the carb and regulator. The fuel transfer holes swell and block the fuel holes causing all kinds of weird problems.
The plunger in the regulator has a silicone valve on one end...make sure this valve outer circumference does not have any flash from the mold or any nicks from the cutter when it was cut off the mold tree.
This has definately been a problem previously....I had 2 engines with this problem.
Also.....the plunger passage through the regulator has been a problem on some engines....machining chips...swarf...have been known to be in the passage causing the plunger to bind and mess up the mixture and cause leaks from the intake when the tank is pressurized.... also you cannot adjust the idle and transition mixture.
Remove the throttle barrel and look at the idle slit in the barrel. This slot collects trash and some engines have had chips in there as well. You can run a razor blade through the slot to make sure it is clean.
Remove the n/v and backflush with alcohol...then blow out.....cleans out any trash.
Have Fun
Dave
06-04-2013, 07:52 PM
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RE: YS 60FS Tuning Help Needed
ORIGINAL: Jim Johns
I think I'm going to tear it down completely and do a 100% cleaning and replace the diaphragm before I continue.
I think I'm going to tear it down completely and do a 100% cleaning and replace the diaphragm before I continue.
You mention replacing "the diaphragm"....On the 45/60 that's actually the least of my worries because it's a tough diaphragm...The more sensitive items in my opinion are the needle valve o-rings and the regulator plunger which are easy to overlook and if damaged or worn will cause problems...The plunger is actually the "important" part as it needs to seal correctly to it's seat in the regulator body...The carb o-rings are usually hard and brittle when I take them apart and will just simply fall apart...
I would suggest you order an o-ring set, diaphragm, plunger and spring...You will also need a gasket set...
Here lies the problem!! Gaskets Sets for the YS 60!!...To my knowledge they are no longer available (unless somethings changed)...Your gonna tear them up when you take the engine apart...What to do?? I'm gonna start another thread as this little detail needs to be addressed...I'm gonna need gaskets and I'm sure others will as well...
Have Fun...
Chuck
P.S. While I was typing Dave addressed some of the same things I wanted to say...Sorry for the redundancy but I ain't gonna delete it...he he
06-04-2013, 11:55 PM
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RE: YS 60FS Tuning Help Needed
Central Hobbys may have some gasket sets left....doubt it though.
Leak Free gaskets were available for a long time but since YS changed to the black gaskets I havent heard about LF anymore.
I would call Central and talk with the owner Al Coomer nad see what he has.
Dave
Leak Free gaskets were available for a long time but since YS changed to the black gaskets I havent heard about LF anymore.
I would call Central and talk with the owner Al Coomer nad see what he has.
Dave
06-11-2013, 04:27 AM
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RE: YS 60FS Tuning Help Needed
I'm thinking the YS 60 FS were designed for a tuned pipe, not sure how it run with a muffler I have 2 YS 60 FS always ran with a tuned pipe no problem. Jeff is right on read instruction and use a tac never had a problem tuning them again with a tuned pipe not a muffler. Just my 2 cents. Pete
06-11-2013, 06:36 AM
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RE: YS 60FS Tuning Help Needed
ORIGINAL: rv7driver
I'm thinking the YS 60 FS were designed for a tuned pipe, not sure how it run with a muffler I have 2 YS 60 FS always ran with a tuned pipe no problem. Jeff is right on read instruction and use a tac never had a problem tuning them again with a tuned pipe not a muffler. Just my 2 cents. Pete
I'm thinking the YS 60 FS were designed for a tuned pipe, not sure how it run with a muffler I have 2 YS 60 FS always ran with a tuned pipe no problem. Jeff is right on read instruction and use a tac never had a problem tuning them again with a tuned pipe not a muffler. Just my 2 cents. Pete
Jim
06-11-2013, 05:37 PM
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RE: YS 60FS Tuning Help Needed
ORIGINAL: Jim Johns
Thanks, Pete. I did a complete cleaning, replaced the diaphragm and cleaned up the holes in the carb & regulator gaskets using a sharpened brass tube. I set the regulator flush and she fired right up. Idles like a champ with great transition, too.
Jim
Thanks, Pete. I did a complete cleaning, replaced the diaphragm and cleaned up the holes in the carb & regulator gaskets using a sharpened brass tube. I set the regulator flush and she fired right up. Idles like a champ with great transition, too.
Jim
