RE: ys 160dz Question ?
Pressurization of the air/fuel charge and top end lubrication.
Posted on: 5/17/2013 10:02 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11514321

RE: Parts for YS .61 long stroke (rear ex)
I would call Richard, he and his guys are usually in the shop as they run every engine they repair before it goes out the door so sometimes emails take a while to get replied to. Last 61 I had ran pipe and header from MAC Products here in the US.
Posted on: 9/18/2012 5:48 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11232196

RE: Parts for YS .61 long stroke (rear ex)
I don't know who the YS agent is for the UK, but I would start there. If not, and you want to call the US, try calling Richard at YS in the US as he used to have some spares left for the older 2 strokes.
Posted on: 9/17/2012 6:09 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11230937

RE: YS-63 Drive hub
Do you mean the drive washer or an actual crank extension? I have seen neither, but that doesn't mean they don't exist.
Posted on: 9/11/2012 7:00 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11224926

RE: YSDZ 160 cam bearing removal from crankcase
I would heat the case up in an oven and holding the case with a welding glove, tap it on the side on a piece of wood to get it out. I know some guys use a torch to heat the crankcase but that would be personal preference.
Posted on: 9/8/2012 5:37 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11221598

RE: 120 decreasing rpm
Thats good news. I am glad to hear the engine is running as it should.
Posted on: 9/4/2012 7:19 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11216840

RE: 120 decreasing rpm
Take a look at the actual needle itself. I have seen and had engines that will wear the taper on the needle into a step due to a long needle extension being used. It will exhibit going from too rich to lean or perfect in a click or two after a long time of no response to turning the needle. If the needle has a nice smooth taper then you might consider sending to Richard far a check up.
Posted on: 8/31/2012 6:43 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11212506

RE: YS 175 CDI Nose Ring
I don't know about Central parts and it might warrant a call to them, but I never had a nose ring that had a gap around it and the engine.
Posted on: 8/20/2012 8:43 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11199661

RE: 120 decreasing rpm
A little resistance is normal. if you are that far into the engine that you have the bearing out change it and the ring at minimum.
Posted on: 8/20/2012 8:41 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11199660

RE: YS 63 overly rich regulator
As long as you do not go under 20% oil content you should be OK. I like a nice smoke trial personally. If it is smoking a lot at idle you could back the idle needle out a taste to lean it. Do not let the idle go over 2300-2400 RPM as at that point you are on the regulator and not the idle circuit.
Posted on: 8/20/2012 8:39 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11199655

RE: 120 decreasing rpm
What do you mean by backed out 1/2 a turn? 1/2 a turn from flush with the regulator body or 1/2 a turn from fully closed? if its 1/2 a turn from fully closed the regulator probably needs some new components, plunger, spring and diaphragm.
Posted on: 8/13/2012 7:39 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11191520

RE: YS 63 overly rich regulator
First issue is the raw fuel, if it is so rich that is it pushing raw fuel out the regulator is not closing. That issue needs resolved first. Since your initial post states you replaced the diaphragm and plunger I am wondering if you replaced the spring as well. As for lapping the valves I know guys who have used toothe paste or baking soda to do that job.
Posted on: 8/13/2012 7:29 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11191510

RE: Muffler keeps loosening up
I've had a lot of people use Jimmy's suggestion with great results.
Posted on: 8/3/2012 6:41 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11179500

RE: 110 FZ pushrod tubes
To replace the tubes you will need to pull the cylinder off the crankcase. Was the engine in a crash and damaged the tubes? If not then the replacement is pretty straight forward but ifi t was crashed that hard you might want to send it in for a repair.
Posted on: 7/10/2012 12:25 PM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11150236

RE: YS 70FZ 16-6 Prop?
I personally wouldn't run a 15x8 on my FZ70 as it keeps it at the lower end of the RPM range. I'd play with props and find one that gives the flight performance you want with about 10K-11K RPM on your particular fuel. Just for comparison I used to runs 15x8 on my 91AC. The 70 is a really strong engine and might swing the 16x6 but it still wants to run in it's happy range.
Posted on: 7/1/2012 8:02 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11138522

RE: YS-115 Rough on Idle
The low end is an air-bleed. out leans it and in richness it. No tank pressure is huge issue. we need to find the cause of that first.
Posted on: 6/28/2012 6:09 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11134939

RE: YS CDI RF interference
I personally have not heard of that, but everyone I know running the CDI is on 2.4ghz.
Posted on: 6/28/2012 6:07 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11134937

RE: YS-115 Rough on Idle
Give us some more info: 1) Prop 2) Plug 3) which fuel 4) RPM at idle and WOT 5) does it slow down and die or speed up and die I have posted this link a lot: http://www.julton.net/Fact%20Sheet%20YS%20Engines.html Worth a read.
Posted on: 6/27/2012 7:25 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11133698

RE: YS 91AC CDI - Lubrication
Interesting conversion, but this is a direct support forum and the 91AC was not offered as a CDI so you might be better served posting this to the general engine forum. I will say that I loved my 1.70 CDI for it's reliable low idle.
Posted on: 6/18/2012 10:14 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11122472

RE: YS120SF Needs Help
Chances are the passages in the regulator have gummed up fuel from sitting in them. Use raw fuel and to clean them. Sometimes a pipe cleaner helps. If you would rather send it in for a good check up, bearing could need help from sitting, you can always send it in to YS Parts and Service. Richard and his guys will give it a good going over and they will test run it before sending it back.
Posted on: 6/16/2012 4:29 PM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11120514

RE: YS-FZ110 dies on idle only in flight
Those bubbles are normal and actually the reason why YS went to a dark blue tube from the regulator to the carb. When you start the engine on the stand what is the idle RPM and how long will it hold the idle? What plug and fuel are you using?
Posted on: 6/15/2012 6:28 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11119017

RE: YS115 wont start
Contrary to Four Strokers comment, YS 20/20 is the usual choice. 20% oil is the minimum suggested and the higher the nitro content the easier the engine is to tune. There have been guys who have made the YS behave on 0% nitro but it is a lot of work on the tuning to make it happy with lower nitro fuels. The higher the nitro content the higher wider the tuning sweet spot is. Keep that in mind while tuning. As for the stuck valve and the fact your mate had the same issue I would look for a different fuel.
Posted on: 6/13/2012 8:28 PM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11117524

RE: YS 91AC
The ST is a 2 stroke not a 4 stroke. I have a 91FZ manual I can send you (same basic engine) just PM me your email address.
Posted on: 6/13/2012 8:23 PM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11117515

RE: ys 91 ac question
A crack in the valve cover will certainly cause you to be lean, but it usually has other issues like idle irregularity and loss of pressure in the fuel system. Some guys "true up" the bottom of the valve cover on 400 grit sand paper. If you decide to di that make sure the sand paper is on a good flat surface. As for other parts, regulator spring, diaphragm, plunger, and get a spare check valve. The check valve is always a good spare to have in the field box. Let us know how it turns out.
Posted on: 6/13/2012 6:28 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11116622

RE: YS115 wont start
That's good news.
Posted on: 6/13/2012 6:02 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11116604

RE: SD-10G broken switches
Here is a link to the Service page. I would give them a quick call and ask. http://www.airtronics.net/index.php/service
Posted on: 6/13/2012 5:59 AM by Author "petec" in the forum "Airtronics Support Forum"
http://www.rcuniverse.com/forum/fb.asp?m=11116602

RE: ys 91 ac question
Good point about who put the parts in the engine and the cam timing. One other thought, before we go any further, have you checked the valve clearence? Alberto, considering a YS can be temperamental due to is high performance and not knowing the history on the repair of the engine, you might want to consider sending it to Richard at YS. You said you are new to 4 strokes and the YS is not like other 4 strokes so making sure you are starting with a good baseline to learn with might help a lot more than chasing symptoms. Once you get the YS figured out they are a great engine, but starting with a problem child makes a lot of people shy away from them.
Posted on: 6/12/2012 9:34 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11115611

RE: YS115 wont start
If the valve is stuck closed and won't open with finger pressure, you would probably be best served by sending it to the UK agent for YS. There may be more internal damage if the valve impacted the piston.
Posted on: 6/12/2012 9:18 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11115592

RE: ys 91 ac question
Sorry for the lack of help guys, I work for a living and have less time these days than I used to have for answering questions due to the wonders of downsizing. Now about fuel coming out of the carb, a fine mist or a few tiny droplets while running is nothing to worry about but a big drops are an issue. We need to know which is it is. The spring in gut regulator could be just old and not giving you the proper pressure. Do not think that stretching the spring to give you a little more pressure is good idea...it's not and you will drive yourself nuts. I bought a used YS years ago and never paid attention to the spring and it was giving me grief, sent it to Richard who did nothing else but swap out the spring and it ran like a top. What are the settings on you HS needle, LS needle and where is your regulator set? Flush, above, or below the housing? The regulator controls the total VOLUME of fuel to the engine. the HS needle cuts the amount back to what it needs for WOT and when the engine transitions it needs more fuel volume to keep from going lean. Remember the old carb on you car had an accelerator pump to help for just this reason.
Posted on: 6/11/2012 5:14 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11114167

RE: YS115 wont start
Try removing the HS needle and pull it through a few revolutions and see if fuel flows out of the opening. Then try starting it after re setting the HS needle.
Posted on: 6/11/2012 4:56 AM by Author "petec" in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=11114154