|
3W.85 vibrating too much
Ok guys, I have a problem with excesive vibration from this engine. I will try to explain my set up and thing I have tried in order to fix this:
The engine turns a mejzlik 26x10 at 6700 rpms. I leaned the low needle until I got good transition and steady idle. Lawn boy Ashless 40:1. Only 9 flights thru it. About 3/4 gallons. The low needle was turned right and left, trying to get rid of the vibration, the idle changed and the transition to full was bad... the vibration was still there. the same was done with the high needle to no avail. The spark plug was medium brown in color, but I still changed it and the vibration was still there. I know that a single cylinder engine has more vibration that a twin, but I`ve had other singles that don`t vibrate to the point that it takes things apart inside the plane. (DA50, ZDZ50, ZDZ80RV) these are relatively smooth engines. I was thinking that the factory timing might be the problem. but in the 3Ws the prop hub has two magnets and the meassurements for seting it are made in degrees. Is there a simple way I can set the timing right using milimeters? If you guys think that there is more to it than the timming, please let me now as I`m running out of ideas. Any advice? John |
RE: 3W.85 vibrating too much
Call ZDZ and ask, there coustomer support is pretty good and they may have a real good solution for you. http://www.rcshowcase.com/
|
RE: 3W.85 vibrating too much
ZDZ would probably LOVE offering support for the 3W85 :)
Try bobby at http://www.cactusaviation.com/ Chad |
RE: 3W.85 vibrating too much
ORIGINAL: GmanBill Call ZDZ and ask, there coustomer support is pretty good and they may have a real good solution for you. http://www.rcshowcase.com/ I don't think ZDZ / RCS would give very good support for a 3W engine! |
RE: 3W.85 vibrating too much
It will get better, but it is still a shaker. I have 16 gallons on mine.
I don't think it's a timing issue at all.. its a big powerful, torquey single and the price you pay is vibration unfortunately. Wait till you get 3-5 gallons on it and the engine really wakes up :) the power will make you forget about the vibration :D |
RE: 3W.85 vibrating too much
Sinergy, what does your plane weigh, that has the 3w85 in it? I keep forgetting to ask you.
Chad |
RE: 3W.85 vibrating too much
24 pounds and jumps out of a hover like a hot potatoe :D
|
RE: 3W.85 vibrating too much
ouch hot
hot hot pass it:D |
RE: 3W.85 vibrating too much
I agree with those who don't see this as a timing problem. With all due respect, have you carefully ballanced your prop and spinner, and back plate? This really does make a difference with these single cylinders, and big props. If the engine has good throttle responce throughout its range, I would start there.
|
RE: 3W.85 vibrating too much
What is the plane constructed of? Are you running with the wings on? How heavy is it?
|
RE: 3W.85 vibrating too much
ORIGINAL: juanes1969 Ok guys, I have a problem with excesive vibration from this engine. I will try to explain my set up and thing I have tried in order to fix this: The engine turns a mejzlik 26x10 at 6700 rpms. I leaned the low needle until I got good transition and steady idle. Lawn boy Ashless 40:1. Only 9 flights thru it. About 3/4 gallons. The low needle was turned right and left, trying to get rid of the vibration, the idle changed and the transition to full was bad... the vibration was still there. the same was done with the high needle to no avail. The spark plug was medium brown in color, but I still changed it and the vibration was still there. I know that a single cylinder engine has more vibration that a twin, but I`ve had other singles that don`t vibrate to the point that it takes things apart inside the plane. (DA50, ZDZ50, ZDZ80RV) these are relatively smooth engines. I was thinking that the factory timing might be the problem. but in the 3Ws the prop hub has two magnets and the meassurements for seting it are made in degrees. Is there a simple way I can set the timing right using milimeters? If you guys think that there is more to it than the timming, please let me now as I`m running out of ideas. Any advice? John |
RE: 3W.85 vibrating too much
Thanks for the advice/opinios guys.
The prop is balanced and the spinner too. Those were the first things that I did before I started the engine. And I always start the engine with the wings on the plane, if I don`t do it that way it will feel like it`s vibrating even more. The plane weights 23.4 pounds empty and it keeps flying up even if I pull down on the throttle to 1/3. Keep the ideas coming guys, meanwhile I will just keep flying it to see if I can find anything else or if it gets better with time. John |
RE: 3W.85 vibrating too much
ORIGINAL: krayzc-RCU ouch hot hot hot pass it:D haha |
RE: 3W.85 vibrating too much
One thing that might help is to mount your prop inline with the cylinder or put another way parallel with the connecting rod when at top dead center.
|
RE: 3W.85 vibrating too much
Forgot to ask how you have it mounted. 3W has some specific recomendations on this.
|
RE: 3W.85 vibrating too much
Well I mounted mine as per their instructions and the plate.
|
RE: 3W.85 vibrating too much
I used the alum. mounting plate that Cactus sell for this engine. I will take pictures of the installation today and will post tonight.
The sequence on the install is: firewall-mounting plate-engine. The muffler has the two metal plates conneted to it. Bobby, from Cactus responded yesterday to my e-mail and he said to lean the low needle to 1/2 from closed. I haven`t been able to get to it, but will try it tomorrow. I will keep you posted. John |
RE: 3W.85 vibrating too much
:DJuanes,I'm tuneing my 75ius and it to also shakes like creazy but I think I finally got it to vibrate less changed the prop for a more better balanced one and tuned it a little better right now just trying to get a better idle off of it. but I think they all vibrate alot while in breakin it should smooth out after the breakin. but time will tell. hey buy any chance are u related to juanes el cantante?:Djajajajaja
|
RE: 3W.85 vibrating too much
Hola Juanes,denuevo agian I flipped over my 3w 75 today and it seem's to be getting better considering that it still in the breakin mode but it sound's way better,got my low end ilde set @ around 2.000 1.9000 rpm and the top end set @ 6.800rpm with a 24x10 zinger,I consider when the breakin is over it should run a whole lot smoother dejame saber que tal va su 3w85i?
|
RE: 3W.85 vibrating too much
1 Attachment(s)
Haven´t run theengine again because I´m changing some equipment on the plane. The pictures below are from my engine´s install, let me know if it´s alright as is or if I should change anything.
|
RE: 3W.85 vibrating too much
from what I can see you do'nt have any standoffs on you'r engine I figure you problably do'nt need them? mabe if it where mounted on standoffs you wouldnt vibrate so mucho? mine is mounted on standoffs and @ the beging it vibrated a lot till I finaly got it tuned just about right I only got about 2 gallons of gas on it so I figure it should get better once the breakin is over. and I'm also runing mine at 40:1 and I started he first gallon at 32:1 with 93 octane fuel.
|
RE: 3W.85 vibrating too much
hey Dale Pabajo! You`re right, I don`t need the stand-offs. The engine and plate are installed directly on the firewall. Still the engines sticks out of the cowl about 3/4 inches. I had a ZDZ80RV installed on the plane before, ut I didn`t fly it with the ZDZ. The ZDZ needed 1/2 inch standoffs to get it out of the cowl.
From what I`ve heard, if your engine vibrates and you put standoffs on it, it will vibrate more. The best way of doing it is supposed to be directly to a solid firewall. John |
RE: 3W.85 vibrating too much
juanes1969
u r correct.... |
RE: 3W.85 vibrating too much
I was at an IMAC contest this weekend and saw a couple DA twins runs and I have to say I didnt see much more vibration in the 3W then the twins... there is a little more but if you have sloppy linkages / gears that is always going to show up. The engine is a bit of a shaker but not that bad.
|
RE: 3W.85 vibrating too much
good deal long as it doesn't deadstick life is good :)
|
| All times are GMT -8. The time now is 06:49 PM. |
Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.