OS Max 91fx Shutting off above 3/4 throttle, HELP!
#26
RE: OS Max 91fx Shutting off above 3/4 throttle, HELP!
Why do want to buy a new one? Why not just remove the old one, disassemble it, shorten the clunk line, check the tubes for splits etc, you can make new ones fron brass or ally K&S tube, then reassemble and pressure test. That way you have learnt about the whole system, know that it is satisfactory, and you can go back and re-test the engines?
Evan, WB #12.
Evan, WB #12.
#28
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RE: OS Max 91fx Shutting off above 3/4 throttle, HELP!
ORIGINAL: MDFlyer83
Im starting to believe its the tank as well, I need to source one asap! Anyone??
Im starting to believe its the tank as well, I need to source one asap! Anyone??
MDflyer As often happens trying to replace an exact tank for many, many Arfs did I say a bunch? frequently becomes impossible. In many cases The hardware package and in particular fuel tanks come from the lowest bidder and this can change from batch to batch or container.
Now I don,t recall exactly what arf you are talking about or recall seeing it mentioned in this thread but a very reasonable size tank for a typical .91 fourstroke is eleven ounces. Yes many will say this is not enough and people go rignt on using tanks that are to large and yes doing this sometimes does effect your run from full to empty.
Now I am not saying tank size is your particular problem but what I am saying is this tank is most reasonable for your engine an just five smackers:
http://www3.towerhobbies.com/cgi-bin...&I=LXK831&P=RF
This is a genuine hayes tank with many, many did I say a bunch of advantanges over all the other conventional bung plug tanks. This is not an expansion plug, it uses an 'O' ring type of plug. Just for starters and I am not going to repeat all the advantages, is you can remove and reinstall the plug all you want and it will never leak. Just try removing a conventional plug more than three or four times over a few months and just watch the leaker.
What you need to do is make it fit, use a chainsaw if neccessary but make it fit. OK just a dremel then!
In addition plumb it like the first two pictures and use only a two line system as the pictures illustrates, do not use a third line. If there is a cowl you mearly make two small hole and the airplane is fueled just like the third picture.
Do these things and you will have the best fuel tank set up out there and its a distinct possiblity that your running problems just might be aliviated.
John
On the matter of just opening and fixing the original tank, well many are so bad that I would never use them.
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RE: OS Max 91fx Shutting off above 3/4 throttle, HELP!
I thought I had already stated that the lines have been replaced as well as the line in the tank. The motor is on a Hangar 9 Twist 60. The current tank has a plug that I believe uses a o-ring to seal it, to take out the plug you loosen a screw in the center and the two pieces come apart.
#30
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RE: OS Max 91fx Shutting off above 3/4 throttle, HELP!
ORIGINAL: MDFlyer83
The current tank has a plug that I believe uses a o-ring to seal it, to take out the plug you loosen a screw in the center and the two pieces come apart.
The current tank has a plug that I believe uses a o-ring to seal it, to take out the plug you loosen a screw in the center and the two pieces come apart.
Sorry no that is not a Hayes There are no screws to tighten with the 'O' ring type, the hard plastic plug is popped in and out. What you have is a conventional expansion bung plug tank and they have not really changed any for the better since I beleve the early sixties when they first hit the market.
Hmm Twist sixty great little airplane I suspect. You will likely enjoy it if you have already solo'ed. I have a new one in box that was given to me as a thank you. When I get around to it you can bet it will have a Hayes tank.
But then agine just about every new airplane I put out these days has a genuine hayes. Oh I suppose every once and a while I let one slip through being lazy and all, ya know. The only exception to that is for certain problamatical installations (yours is not one of those) and definatley all the competition airplanes (primarily pylon) I use the pricey but highly effective Bubbless type tanks, mostly Tetra.
John
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RE: OS Max 91fx Shutting off above 3/4 throttle, HELP!
John,
So your suggesting I get a Hayes tank? If so what size? Im not familiar with how they label tanks im guessing its by ounces? I havent solo'ed it yet seeing as its been doing this since I purchased it but ive flown it on RF6 and enjoy it tremendously!
So your suggesting I get a Hayes tank? If so what size? Im not familiar with how they label tanks im guessing its by ounces? I havent solo'ed it yet seeing as its been doing this since I purchased it but ive flown it on RF6 and enjoy it tremendously!
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RE: OS Max 91fx Shutting off above 3/4 throttle, HELP!
Have you tried a different jug of fuel or borrowed some from a buddy? I didn't see where you tried that and it fixed my friends engine with a similar problem a week ago. His fuel had gone bad. Also got a bad jug of fuel from the hobby shop once - problems started with the new fuel.
#33
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RE: OS Max 91fx Shutting off above 3/4 throttle, HELP!
ORIGINAL: MDFlyer83
John,
So your suggesting I get a Hayes tank? If so what size? Im not familiar with how they label tanks im guessing its by ounces? I havent solo'ed it yet seeing as its been doing this since I purchased it but ive flown it on RF6 and enjoy it tremendously!
John,
So your suggesting I get a Hayes tank? If so what size? Im not familiar with how they label tanks im guessing its by ounces? I havent solo'ed it yet seeing as its been doing this since I purchased it but ive flown it on RF6 and enjoy it tremendously!
What I meant was if you have solo'd yet? On any airplane, not a sim and not if the twist has flown.
If this is your first airplane then it is an exceedingly bad idea.
Yes since you seem frustrated by the inability to find a tank that is the stock tank for the twist then yes I did suggest using a hayes which I did provide a link(post #27) to a hayes which may work and it will be neccessary for you to check the dimensions at that page and measure your airplane and see if it will work.
I suggested the new Hayes since you posted you might try a new tank.
John
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RE: OS Max 91fx Shutting off above 3/4 throttle, HELP!
[/quote]What I meant was if you have solo'd yet? On any airplane, not a sim and not if the twist has flown.
If this is your first airplane then it is an exceedingly bad idea.
Yes since you seem frustrated by the inability to find a tank that is the stock tank for the twist then yes I did suggest using a hayes which I did provide a link(post #27) to a hayes which may work and it will be neccessary for you to check the dimensions at that page and measure your airplane and see if it will work.
I suggested the new Hayes since you posted you might try a new tank.
John
[/quote]
As far as the Twist being my first plane im not at all concerned about it. Im 100% confident in my ability to fly and have solo'd a trainer with ease. Ill have to take a look at the fuse to see what the dimensions are and if the Hayes will fit.
Thanks again John.
If this is your first airplane then it is an exceedingly bad idea.
Yes since you seem frustrated by the inability to find a tank that is the stock tank for the twist then yes I did suggest using a hayes which I did provide a link(post #27) to a hayes which may work and it will be neccessary for you to check the dimensions at that page and measure your airplane and see if it will work.
I suggested the new Hayes since you posted you might try a new tank.
John
[/quote]
As far as the Twist being my first plane im not at all concerned about it. Im 100% confident in my ability to fly and have solo'd a trainer with ease. Ill have to take a look at the fuse to see what the dimensions are and if the Hayes will fit.
Thanks again John.
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RE: OS Max 91fx Shutting off above 3/4 throttle, HELP!
The twist is not a bad choice, to each his own. Alex and I have set the low rates on a very low setting as wel as the high rates. Im sure ill have no problems with this plane. Thanks for the opinion though!
#37
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RE: OS Max 91fx Shutting off above 3/4 throttle, HELP!
So you have gone through training then and have solo'ed with a trainer plane? If so the Twist shouldn't be too hard for you to transition to, just pay attention to how much you roll in the turns unless you like going upside down.
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RE: OS Max 91fx Shutting off above 3/4 throttle, HELP!
Ive solo'd the trainer with EASE and I know ill transition into the Twist without a hitch. Ill even post a video of my first flight with her.
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RE: OS Max 91fx Shutting off above 3/4 throttle, HELP!
Well UPDATE UPDATE UPDATE....
Alex just got back from his vaca and he came across a fuel tank to possibly cure my fuel cut woes. Long story short it did the same thing! Frustrated he decided to pull the fuel line off of the muffler and the motor ran for about 8-10 seconds. Since there was really no change he then put some gas fuel line which is a smaller inner diameter and it seems to have fixed them problem.
Once we got to the field we did some fine tuning and decided to put her in the air. Well, it didnt idle low enough and from 3/4 throttle to full didnt make a difference either so back to the drawing board. Finally after checking, testing, checking, testing, and checking we decided to throw a new glow plug in her and low and behold we could acheive a perfect balance! She flys great and after 2 flghts im completely happy!
So, heres a list of what was done to fix the problem:
1. New fuel lines and tank
2. New glow plug
3. 2 hrs of tuning
I believe the fuel lines are what brought it back to life but the tank could of helped as well. A big thanks to everyone for their suggestions! This site has helped me greatly.
Alex just got back from his vaca and he came across a fuel tank to possibly cure my fuel cut woes. Long story short it did the same thing! Frustrated he decided to pull the fuel line off of the muffler and the motor ran for about 8-10 seconds. Since there was really no change he then put some gas fuel line which is a smaller inner diameter and it seems to have fixed them problem.
Once we got to the field we did some fine tuning and decided to put her in the air. Well, it didnt idle low enough and from 3/4 throttle to full didnt make a difference either so back to the drawing board. Finally after checking, testing, checking, testing, and checking we decided to throw a new glow plug in her and low and behold we could acheive a perfect balance! She flys great and after 2 flghts im completely happy!
So, heres a list of what was done to fix the problem:
1. New fuel lines and tank
2. New glow plug
3. 2 hrs of tuning
I believe the fuel lines are what brought it back to life but the tank could of helped as well. A big thanks to everyone for their suggestions! This site has helped me greatly.