Is my Hyper .21 carb. bad??
09-11-2006 | 04:59 PM
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From: Ballwin,
MO
Is my Hyper .21 carb. bad??
Ok, I cannot seem to get this car tuned right, and the HSN seems to be very loose.
Symptoms are -
It does not seem to run really fast. I have a .27 engine, "Team Infinity" brand, that runs like crazy... and I thought it should compared to the .21. But I've been told the .21 Hyper should actually run as well or better than this brand of .27. It doesn't. Not even close.
Won't hold a tune.
Doesn't want to reliably start.
At times, it doesn't want to let you prime it. The air keeps pushing it back into the fuel, even though the fuel line is run well.
To get it to run good, the needles need to be much more lean than "manaul specifications"
I wish somone here could see it run in person, but based on what I've said here - is the carb bad? The engine looks good from what I can tell and seems to have good compression. How would I know for sure if it has good compression though? It seems pretty tight to me.
Any advice is welcome. Do I buy a new carb?
Or just sell this engine and pick up a new one. If I buy a new engine what should I get for the Hyper 7?
Thanks
PS - I bought it used, so I never saw the .21 run as new... so I don't have anything to judge it by as far as that goes.
Symptoms are -
It does not seem to run really fast. I have a .27 engine, "Team Infinity" brand, that runs like crazy... and I thought it should compared to the .21. But I've been told the .21 Hyper should actually run as well or better than this brand of .27. It doesn't. Not even close.
Won't hold a tune.
Doesn't want to reliably start.
At times, it doesn't want to let you prime it. The air keeps pushing it back into the fuel, even though the fuel line is run well.
To get it to run good, the needles need to be much more lean than "manaul specifications"
I wish somone here could see it run in person, but based on what I've said here - is the carb bad? The engine looks good from what I can tell and seems to have good compression. How would I know for sure if it has good compression though? It seems pretty tight to me.
Any advice is welcome. Do I buy a new carb?
Or just sell this engine and pick up a new one. If I buy a new engine what should I get for the Hyper 7?
Thanks
PS - I bought it used, so I never saw the .21 run as new... so I don't have anything to judge it by as far as that goes.
09-11-2006 | 05:21 PM
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From: Lutcher, LA
RE: Is my Hyper .21 carb. bad??
The carbs on the Hyper .21 are notoriously sucky. If you can find an OS 20E carb on ebay(there's one now for $60), that would be the ticket. Also... how many gallons of fuel have been run through that motor? More then likely, get yourself a new budget motor... an OS .21 RG if you can happen to find one (discontinued), use the carb on the Hyper .21 until it dies, then throw it on the OS .21.
09-11-2006 | 06:08 PM
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From: Ballwin,
MO
RE: Is my Hyper .21 carb. bad??
It's had quite a bit of fuel run through I would bet, but it looks very nice. The head is still very smooth and light colored.
one thing I noticed is the throttle "plunger" (what's the real term for this?) doesn't expand and contract smoothly, but is dented in when you squeeze the throttle and then "pops" out after a second.
What would be race quality engine/carb I could just put on this body? still an os .21? Or should I look for somethign else? I don't want to spend $300+ but I would flip a couple hundred for it.
What about the STS engines?
Thanks
Tim
one thing I noticed is the throttle "plunger" (what's the real term for this?) doesn't expand and contract smoothly, but is dented in when you squeeze the throttle and then "pops" out after a second.
What would be race quality engine/carb I could just put on this body? still an os .21? Or should I look for somethign else? I don't want to spend $300+ but I would flip a couple hundred for it.
What about the STS engines?
Thanks
Tim
09-12-2006 | 05:52 AM
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From: Coral Gables,
FL
RE: Is my Hyper .21 carb. bad??
Everyone always talk about how the carb is so bad on the hyper 7 .21. I didnt have any problems with mine, and it was only my second nitro engine ever. Just take your time tuning it up the first time, and from then on youll only need to make small little adjustments to keep it where it is.
09-12-2006 | 07:13 AM
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From: Rossville,
GA
RE: Is my Hyper .21 carb. bad??
Try a little lock tide on the hsn to help hold it in place that was the problem i had with my carb on the 21 and that is how i fixed it not a whole just enough to hold it when you set it.
09-12-2006 | 08:47 AM
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From: Virginia Beach,
VA
RE: Is my Hyper .21 carb. bad??
http://www.ofna.com/forum/viewtopic.php?t=4339
This is a great help. But it sounds like something in your carb is messed up if the throttle slide is binding up. It sounds like you may have an air leak somewhere as well, be it inside the carb or the fuel tank/lines, I do not know. As long as I have the needles somewhere in the ballpark(to where it starts up so I can let it get to temp) I'm all set. One thing to realize though is that you have to go in VERY small increments. 1/4 turn is a huge difference. I'll bet your HSN is turning on your(from the vibrations) and changing your tune and/or there is air getting past the o-ring making it finicky. Get new o-rings for your carb and start back at square one.
I have been typing my fingers off helping racers with the carb issues on the Hyper 8 port engines, and came to a realization that it makes more sense to type it one more time and make it a sticky for everyone to see...
The carb on the 8 port engine is a great carb, and I get frustrated when others say differently. The trick is to "know" the carbs needles, and the one that will get people every time is the midrange needle. There is a misconception that you should never touch the midrange, and I completely disagree. Learn how the midrange needle works, and adjust it accordingly...
The very first thing every 8 port owner should do is remove the entire high speed needle housing off of the carb body. Set the Midrange needle to flush with the carb body, and then look into the hole (where the high speed needle housing was) and look for the hole in the midrange needle, it must be in alignment with the high speed needle. The midrange needle has only 4 openings on it, so once you find the right location, all you'll have to do is remember that you can only make quarter turn adjustments on the midrange needle.Once you have the needle hole in the center, take a file and put a small scribe on the carb to make it obvious where the setting should be, and if it ever walks, you be able to quickly tell that its out of adjustment, and reset it...
I run the midrange needle 1/4 turn out from flush...
For my setup, the low speed needle will be sticking out from flush about 2.5-3.5 turns out...
Tune the engine a bit on the rich side on the bottom needle, and run it at about 250ish, and it will be a very fast engine....I like the Ofna PCR (#19789) pipe with a double bent manifold, and I use Mugen Alum. clutch shoes with Mugen 1.1 springs...
I hope this helps...
Have Fun...Burn Nitro...
The carb on the 8 port engine is a great carb, and I get frustrated when others say differently. The trick is to "know" the carbs needles, and the one that will get people every time is the midrange needle. There is a misconception that you should never touch the midrange, and I completely disagree. Learn how the midrange needle works, and adjust it accordingly...
The very first thing every 8 port owner should do is remove the entire high speed needle housing off of the carb body. Set the Midrange needle to flush with the carb body, and then look into the hole (where the high speed needle housing was) and look for the hole in the midrange needle, it must be in alignment with the high speed needle. The midrange needle has only 4 openings on it, so once you find the right location, all you'll have to do is remember that you can only make quarter turn adjustments on the midrange needle.Once you have the needle hole in the center, take a file and put a small scribe on the carb to make it obvious where the setting should be, and if it ever walks, you be able to quickly tell that its out of adjustment, and reset it...
I run the midrange needle 1/4 turn out from flush...
For my setup, the low speed needle will be sticking out from flush about 2.5-3.5 turns out...
Tune the engine a bit on the rich side on the bottom needle, and run it at about 250ish, and it will be a very fast engine....I like the Ofna PCR (#19789) pipe with a double bent manifold, and I use Mugen Alum. clutch shoes with Mugen 1.1 springs...
I hope this helps...
Have Fun...Burn Nitro...
09-12-2006 | 02:13 PM
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From: Queen Creek,
AZ
RE: Is my Hyper .21 carb. bad??
ORIGINAL: trpastor
. . . HSN seems to be very loose.
. . . HSN seems to be very loose.
EDIT: Apparently HoBao (if they are the ones that make the Hyper engines) realized that there needed to be a change to the seal design. When you order a set of replacement seals they are much thicker than the ones that come installed on the carburetor from the factory.
09-14-2006 | 09:03 AM
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From: Ballwin,
MO
RE: Is my Hyper .21 carb. bad??
Ok, so where do I buy o rings for the .21? Tower hobbies has the engine but no seals for it....
Anywhere else I can find them? Can I use o rings from another engine?
Tim
Anywhere else I can find them? Can I use o rings from another engine?
Tim
09-14-2006 | 11:18 AM
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From: Huntsville,
AL
RE: Is my Hyper .21 carb. bad??
09-15-2006 | 08:50 AM
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From: Queen Creek,
AZ
RE: Is my Hyper .21 carb. bad??
I would call Nitrohouse and talk to Rob. They don’t have a complete o-ring kit listed, but they can get one made up and send it to you.
I have owned a couple Hyper 8 ports and tested different carbs. You will lose performance when using the OS 20e carb. The stock carb is a great carb if setup correctly. But what happens too is the o-rings dry out and then it makes it impossible to tune. Replace the o-rings and you will have a cheaper fix and better performance. Then tune it like Rob from Nitrohouse was quoted above.
I have owned a couple Hyper 8 ports and tested different carbs. You will lose performance when using the OS 20e carb. The stock carb is a great carb if setup correctly. But what happens too is the o-rings dry out and then it makes it impossible to tune. Replace the o-rings and you will have a cheaper fix and better performance. Then tune it like Rob from Nitrohouse was quoted above.
09-15-2006 | 03:01 PM
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From: Queen Creek,
AZ
RE: Is my Hyper .21 carb. bad??
Part no 53061 is the complete seal set for the Hyper carb, just ordered one for my buddy's engine a couple weeks ago (also from Nitrohouse).
