Wasson

It is fairly unusual to find a pump that fails to operate from new. However the symptoms you describe are not untypical when trying to start a new engine for the first time.

You have done the right thing by priming the engine all the way through to the check valve.

You say that the pump is showing no sign of pumping when the engine is cranking. Is this with the line to the check valve disconnected or connected? The reason that I ask, is that if a new engine has been sitting for some time before being started, the rubber diaphragm in the check valve can sometimes stick to the valve seat, thereby blocking or partially restricting the flow of fuel. This can easily be fixed by carefully taking the check valve apart and dipping the diaphragm in some neat fuel.

If the pump is pumping OK with the line to the check valve disconnected, then the above fix should get you underway. For the first 4 or 5 starts on a new engine, it can also be helpful to put a few drops of fuel directly into the “air side� of the carburettor in addition to priming the pump in the way that you describe.

Hope this helps

Regards

Bob

jim woodward

Sir - Functionally the motor should run if you have air, fuel, spark. From your description, the pump is not providing the fuel supply. It is possible that within the interior of the pump, that something is stuck and blocking its funtion. If you are comfortable with the procedure, I would recomend "flushing out" the pump. Be careful if you do this on the plane. You can back-flush through the fuel lines. Or, dissasmble the pump on the work bench and ensure the fuel ports are all clear.
Jim

pattratt

My Feedback: (1)

topiwala
This happened to me on my first attempt to start my CDI.
The problem was manufacturing trash in the pump regulator housing between the diaphram and the check valves which kept one of the checks open thus not pumping fuel. Open it up and carefully check everything there being very careful not to loose a spring or white check valve. A good way to check this is to remove both lines going to the pump and then put a short fuel line on each nipple of the pump and gently blow thru the tubing. You should not be able to pass air thru the pump. If you can there is a check valve problem.

Dick

topiwala

Gidday Dick,
Actually I was able to pass air and fuel through the pump/regulator without any restriction. I did confirm in my mind, after this, that it is a pump/chekc valve issue. I had a look inside and there is not sign of FOD, debris. Looks clean to me.I was hesitant to go too deep into this as the motor warranty would be affected. I will feeback on findings from YS, when the motor is returned to me. Thanks

pattratt

My Feedback: (1)

Hi All

Thought I would update my progress on the CDI. I now have almost 100 flights on the returned engine and all is finally going well. On my last update I had changed back to the 19.5x11.5 prop so that I could get at least 50 of the flights in summer time heat to evaluate the lonjevity of the pump utilizing the forced air cooling after landing. I am able to turn this prop 7300 RPM which makes Richard happy and continue to use Cool Power 30% LS Fuel. During the last 50 flights I experienced major plug problems that was requiring plug changes every 8 to 10 flights and at $24 a piece it was getting very expensive. The symptoms were exactly the same as a pump going bad which really confused the the issue. The problem turned out to be the ignition cap on the CDI being only slightly less tight [not loose] that caused the cap to fracture the upper porcelain on the plug causing it to miss, run erratic, and not be able to get a correct mixture setting! After discovering the plug problem I crimped the cap tighter and put a tie wrarp around the cap so it could not spread. It made the cap almost impossible to put on but once there it did not move. I also tied the lead going to the cap down to the intake tube so that the movement of the Hyde mount could not move the cap on the plug. It worked!! Not a single plug failiar since. The good news is that I found two other manufactures of plugs that will work well in the CDI. M8 from Todd Syssa at $8.56 each in quanities of 6 [NGK Plug] and RimFire from C&H ignition. Both work well.

The biggest thing I learned about the CDI is that almost any type of problem, Too lean, Too Rich, Too hot, Bad plug, Bad CDI box, Rich pump setting, Lean pump setting, Worn Pump, Bad punp check valve, Worn pump diaphram, all will give exactly the same "Synptoms!" [Won't start, Won't stay running, Popping, Coughing, Unreliable idle, Unable to set top end mixture correctly, die in the air, and hit so hard it takes the cheek cowl out] This is not an easy engine to learn!!

At this point I am having zero issues with the CDI but find it embarassing and the butt of many jokes having to give the engine a "Blow J__" after every flight. It does work!! Hopefully this requirement will go away after the introduction of the YS DZ 175 CDI and we can get the 175 pump that is supposed to fix all the heating and fuel boiling problems! Based on the continued mass exodus to electric I am not sure how long there is going to be a viable Pattern YS Market?? As most know I am in the process of putting together a "Visa" and will be testing out "Pattern Electric" this winter! The addition of an electric to the Japanese team has really sent shock waves thru the IC Engine community! The next two years are really going to be interesting!!

Finally, I want to thank everyone who has contributed to this thread as I feel there is a wealth of information that will make this thread a real "Data Base" for those running the YS CDI engines for some time to come!

Regards
Dick Mundee

jim woodward

Dick - I'm glad to see you have found a root cause of intermittent running. Since you have brought in the Electric versus Glow debate a couple times though I'll add my 0.02. I'm not aware of any pilots that made the switch to electric and saw their scores or National placings go up. Maybe people like flying electric; but I do not see the supposed "inevitability" of eletric F3A due to increased flight scores. However, I have seen other peoples scores or placings go down hill after switching to electric.

Thanks,
Jim

Gregg G

My Feedback: (7)

Hey Jim, did you move? I noticed Guntersville.

rcpattern

My Feedback: (45)

Jim,

After watching VERY closely at the NATS this year, i can definitely finally see the advantages. In years past there were short comings of electric, but they are now gone. The electrics produce in my opinion more power, and certainly more torque. On a calm day like we had much of the finals, NOT having a smoke trail was a major advantage. You can still fly glow and be competitive, but this is the first year that I've actually seen the advantage fall in the electrics favor. Another aspect is that in the finals, electric is the dominant power source, therefore anyone flying glow is already in a minority. It can still definitely be done, but after switching 2 months ago and really getting some time on the electrics, I can fly every bit as big and fast as I used to, without the headache of a smoke trail on a clear day. Also, you don't have a smoke trail giving away small bobbles, or if you need to add a little power at the top of a stall turn. I've been pro glow for many years, but this year I finally saw that there are advantages. I don't necessarily think I'll score better with electric, but it definitely seems to be less work, and less things that you try to hide will show up. They certainly aren't bullet proof, but I am very happy after making the switch.

Arch

apereira

Jim,

I'm sure you know I agree with you, electric will not make you a better pilot. I remember at the worlds I told Quique at the banquet, I was sure he would score higher if would still use the YS, the electrics on that perfect blue sky was not as beautiful as the smoke trail on the others, and anybody likes that, specially judges.

I also remember Tetsuo Onda in Argentina, on the first or second P, on the figure 9, he was really "drawing" the maneuver, to the point where on the vertical down line he just kicked the throttle and cutter the horizontal smoke trail, that was aaaawesomeee.

The YS are difficult engines, but I have to admit, they are not for everybody, high performance machines are like that.

After 15 years flying YS, I can't think on changing, I do have an Onas with an Axi and the Xurama with the Neu(not finished(I'll let you know on that one Jim)), but I can't see my Axiome on an electric motor, no way.

Arch, the YS on 10% oil will not make any smoke trail, one of the French used it as some other European pilots, and it was really invisible.

Regards

pattratt

My Feedback: (1)

Hi Jim

I can't speak for anyone else but for me it had nothing to do with scores. It had to do with increased performance and reduced maintance especially engine and airframe. Score never entered the equation! The other reason is the dwendling options in airframes and the 0 options in power.[YS]

Dick

jim woodward

Calm day? What about a windy day? In my opinion, the electric planes look "lost" in the sky crabbing at wierd angles without a frame of reference. When you are pulling uplines and streaming smoke, the 'crab' angle makes all the sense and looks "right" - E-models look lost in space on windy days and this is not about power, rather the relative angles needed to make the manever look right compared to the wind condition.

A few of us discussed the smoke trail quite a bit on a windy Sunday at the last contest and while the bubbles in the smoke were disucssed, I was quite happy to hear each of the judges say, "... we know its windy because we can see you flying a straight line, but later on the smoke bubbles." IE - the smoke is not causing or revieling downgrades that are not already evident.

It goes both ways - lost in space on a windy day, or smoke trail on a calm day. I think the smoke trail eccentuates good flying just as much as bad flying. I fear not the smoke !!
Jim

PS - on a Hazzzzzzy kind of day, the smoke trail helps me see/track the plane around the rolling circle when otherwise is darn near invisible at times. This was noted as a advantage to me, by my fellow E-flyers

rcpattern

My Feedback: (45)

Jim,

With that argument, the guys running low smoke fuel are now at a disadvantage as well. I really don't notice the crab angle looking odd without a smoke trail. On a really windy day you can't see the smoke trail anyway. I can now fly every bit as fast, if not faster on a windy day without any problems on the electric side. The motors, props, and batteries have caught up. I watched Dave Lockhart earlier this year on a windy day and he was faster than me with glow. Now that I'm flying electric with his setup, I can do exactly the same thing. When there was wind at the NATS this year, the electric guys no longer have the problem of flying close in and slow. Everyone in Masters and FAI were flying out and HUGE with no issues whatsoever. The electrics have finally caught up to the glow guys with the newest stuff that is out there. I know what you are saying, and I could've given the EXACT same speech 4 months ago. I was a die hard as anyone on the glow, but having watched very closely this entire year, and at the NATS, I can see the balance of power shifting to the electrics. Hence the reason I made the switch. In my opinion they are of at least equal power, especially with the shorter sequences now. Glow is certainly a viable option still, but electrics are now every bit as viable.

Arch

jim woodward

Arch - its not just the power systems that make speed. Airplanes like your Wind, Visa, Integral, are "clean" planes, not as draggy, and allow for more speed as well. Go out and enjoy charging batteies, but don't look for affirmation from the "slimmy" side
Jim

rcpattern

My Feedback: (45)

Jim,

Not looking for any affirmation. Perfectly content with what I'm flying now.



Arch

Gregg G

My Feedback: (7)

Jim, don't mean to keep bugging you but are you living in Guntersville now?....

Greg

rcpattern

My Feedback: (45)

Greg,

I think Jim moved up to AL a few months ago with a job change.

Arch

jim woodward

.. Yes- we moved to Guntersville following work and such.

cchariandy

After 3 years with a 170 powered Integral (the last year with the CDI). I switched to a more draggy Xigris but powered it with Plettenberg. My initial impressions was that the new e-powered set-up, even in a more draggy plane, was very fast...maybe even too fast. After a few more flights I simply flew a bit further out and bigger than I did with the YS.

I have to admit that I feel the newest e-set ups has more speed and power than the YS in any condition.

The Xigris and Integral are very similar but the e-powered Xigris feels more solid and responsive....the Int now feels like a truck with wings.

Colin.

jim woodward

Hi Colin,

What kind of prop were you using on the Plett (no doubt a great e-motor)? A lot of people run the 21x14. Maybe in YS speak, that compares to a 17x13. However when the 22x12 was the favorite prop, there was no comparison in overall speed envelope from the Glow to E setups. Now that E setups are turning away (in the USA at least) from close and slow, the YS guys can stop trying to emulate it as well. Personally, I'm happy with the 18.1x11 right now versue the 19x11 on the Passport. Works great on this airframe. If it were less draggy, I'd different props.

If I put a 17x12 on it it goes ballistic. YS guys have a lot of options with props for various conditions. Its important not to get locked into one.

Thanks,
Jim

cchariandy

I'm using the APC 20.5X14 and Chris Moons batteries....have'nt tried anything else.

Somehow, everything just seems to work well on the this airframe...CG, prop etc so I havent changed a thing since the first flight. I flew the 18.1X11 on both the CDI and standard 170 and liked it. I find that my left hand moves less for medium power stuff with the e-plane and a bit more with the high power maneuvers for e-power. I have the throttle curve linear for the e-plane so I can add some expo and make it more similar to YS power but I prefer the extra torque in the middle.

Colin.

jim woodward

Thanks Colin - I use a throttle curve that raises the low-end a bit (easier for stall turns), flattens out through the middle, then climbs sharply in the last 25% of stick movement. Also, I do not run carburetor stacks. No reason in my mind to limit power in any way .
Jim

cdodom

The 18.1x11 is a great prop for the 170. I liked the constant speed of the 19x11 but was lacking that extra power at the top of different radius. The 18.1x11 is the perfect prop for pilots that like to fly big and far out.

topiwala

Hi All,
I just got my 170 CDI back from YS japan after I had to send it brandnew back to YS to troubleshoot and address 'not starting' issues. The engine would not prime. I put it down to pump issues. Well its back and it fired up first time without a hiccup. The pump easily primes just by turn the prop back and forth around the bottom end of non-compression stroke. I don't even have to crank it over with a starter to prime. I've found this the best way to prime. And then switch on ignition and engage starter...sweet!!No back fire or kick back like my previous 160dzs and 140L
The one thing I never got from YS Japan, was any feedback on what they actually found wrong with the engine, even after repeated email requests. Though I have noticed a different diaphragm material in the pump housing (orange). And also a new check valve. Either way, the engine is running so well, that I want to do a few more ground runs just to listen to it!!!! Sweet as a sewing machine.
Thanks to YS Japan in addressing my issues.

jim woodward

Glad to hear Topiwala. My 170's have been running really sweet this year and carried me through to some top finishes as the year has winded down. Very proud to be running YS!!
Thanks Jim

(disclosure)
Proud user and Team Futaba, YS, Morgan Fuels member

bjr_93tz

Just a quick question regarding the 170 pump issues, as I'm looking at buying a new pump for my 170cdi to replace the one that's on there now.

Are the pumps for the 175's available and a prefered drop in replacement, or should I stick with the original 170 pump?

After nearly a year of perfect running(not a single deadstick from brand new), 3 weeks ago it spat the dummy and deadsticked on 3rd flight of the afternoon and it's been deadsticking ever since. I'm just about ready to melt down my 170cdi for scrap metal, the only options I have left now are to pull the cdi and run a glow plug to isolate the cdi from the running problems or replace the pump. I've exhausted most other options ...