Hyper 7 running too rich?

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Revo Rancher

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Well, finally got enough time and good weather to break in my Hyper 7 PCR RTR. This model has the Hyper 7 .21 8 port engine. I run the stock plugs and use Byrons 2500 (25%) fuel.

I followed the instructions on the settings for the carb for break in. If my memory is correct, they suggest 5 turns out from full in for the HSN, flush for the mid needle, and 4 turns out for the LSN. You the idle the rig for 3 minutes then shut off until fully cooled, engine at BDC. You do this four times. During this time I had good idle and it finished the sequence just fine. I had to replace the glow plug after this as it would not start for start number 5. I checked the glow plug on the glow plug igniter and it was completely dead. (Yeah, I checked the battery on the igniter, too)

Anyhow, new plug, fresh tank of fuel. Starts fine. Feed it throttle. It stalls. Start again, feed throttle, but even more slowly, gets moving. I can get it up to about 25 miles and hour after little bit of slow throttle for half a tank, but anytime I hit the throttle fat or try to reaccelerate after letting off the throttle it stalls. I lean it (turn HSN needle in) 1/2 turn. Worse now. Run it around until hot, then lean another 1/2 turn. A little better. Still stalls when pushing throttle too much. Lean another 1/2 turn. (HSN) By now, I am turned in more than the post-break in recommended setting of 4 turns out from all the way in for HSN. Still running better, but really spitting out tons of fuel and you can really hear it sputtering, like it is full of fuel. Now it is dark so I quit for the night.

Temps, BTW, are anywhere from 110 to 138 after running it around. Recommended per OFNA manual is 260, and 220 for long engine life.

Q: Should I lean the HSN some more? I do not think I am lean enough which explains my poor engine response and dumping of fuel, and the low temps.

I have two 2.5 TRX motors that broke in and run better than this!!!!
 
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hi revo rancher, i have read your msg and can honestly say i have no idea. i am running 20% fuel and a medium glow plug. my car only picks up speed if i go in an oval whilst turning left, if i turn right at all the revs die and i have to start the whole process of bulding up the revs. have you had your revs high at all where the car sounds like its run in ok? like i say when i'm nearly out of fuel it picks up revs and goes fast but then when i refuel or let the revs drop its once again back to the oval to build up the revs. i really cannot understand why were having this trouble, have you seen any other threads that relate to hyper .21 break in trouble?
 
its your LSN setting not your HSN thats causing you problems. return your HSN to the recommended 4 turns out. then start leaning out your LSN setting by 1/8th a turn at a time. after changing the setting, slowly run the car up to speed to clear it out, then check to see if you can punch it. if it dies again, lean the LSN again and repeat the procedure.

then you can fine tune your HSN. you want to make sure that at full throttle is has a consistant good trail of smoke, and it doesn't sound like its over-revving. you will want to listen to see if its clearing out, you will know it when you hear it because it wont sound blubbery anymore.
 
i have the hyper 7 PBS with the 8 port motor like you guys. i did not have any problems at all and my motor revs high. i did not use the break in procedure that ofna recommends. this is how i broke in my 8 port...

-i went over the factory settings and i checked them on my carb. the settings in my manual said 5 turns out HSN, mid range needle flush, low speed needle 3.5 turns from flush.
tank #1
-i started my motor and let it idle through half of a tank, then shut it off and put the piston at BDC. i let it cool for 15-20 minutes.
-i restarted my motor and let it run through the rest of the tank. after that i let it cool at BDC for 15-20 minutes.
tank #2
-i started up the motor and it started up on the first couple of pulls. i tried to run it in small figure 8's but whenever i would give it gas it would stall. i had to lean the low speed needle a half turn and the high speed needle a quarter of a turn just to get the car to move.
-i ran through the whole tank doing figure 8's. i went very very slow. and i did them on asphalt, not grass.
tank #3
-i leaned the LSN a quarter of a turn and the HSN a quarter of a turn.
-i did a half of a tank doing figure 8's a little faster than before. i leaned the LSN a quarter of a turn and did the same to the HSN. then i turned the motor off and put the piston at BDC. i let it cool for 15-20 minutes.
tank #4
-now i started to do some mid-speed runs up and down my street. i did some accelerating and stopping for this tank. i did this for 1 whole tank while checking my temps the every couple of runs.
tank #5
- i started to fine tune the motor for performance. i was still doing runs up and down my street. but i was going full speed and accelerating hard. i did this for 1 tank. but when adjusting the carb i made extremely small adjustments.
tank #6
-i went to the school yard and had some fun!!! but i did check engine temps every once in a while, and i made sure that there was always a blue trail of smoke coming from the exhaust.

that is how i broke in my motor and its starts on the first couple of pulls every time, even when its cold outside. i also have no performance problems whatsoever. maybe if you got that infamous OS carb that everyone talks about, but i dont really see that that carb is neccasary.

i am running 20 percent fuel and I'm still running the same glow plug that came with the car. i havent had to change it yet.

try leaning out your HSN a little bit more and when you lean out your HSN you might have to richen the LSN though. make sure you are adjusting the right needles. the black needle on the throttle is the LSN and the gold needle on the carb body under the HSN needle assembly is the mid-speed needle. i also found that with carb that comes with the hyper it is somewhat of a balancing act between all of the needles. if you adjust one needle you will probably have to adjust another needle to get the best performance. its kinda lame but once you get it the 8 port motor screams and it holds its tune well for me.
 
CorradoPsi is correct. It's your LSN that needs to be leaned. Reset your HSN to recommended settings for the tank you are on.
DO NOT adjust the MRN.
Lean the LSN only 1/16 in, then run it again. If it's still blubbery and wants to stall, lean it another 1/16th. Check your temps at idle, till they don't rise anymore, then continue with the break in.
Don't be looking for performance yet, you're still breaking it in. Take your time, it will pay off in the end.
 
What should the idle temps be? I am having the same prob with my sirio .27r.
 
seal that engine up for all its worth w/o2 sensor safe sealant (gold tube).

and dump the hyper carb for an OS 20e. problem solved.

-Ult
 
.21Rc10GT said:
What should the idle temps be? I am having the same prob with my sirio .27r.
Sorry, I'm giving temp info in 3 different threads, and I missed it here.
During break in, keep it between 170 and 180. That's still a little on the rich side since it's still breaking in, but at least it's at a point where it will heat cycle properly. When it's running at a higher throttle, look for about 240.
 
OK Rolex and Corradopsi, just reset the needles. Got it started. Ran like crap, and kept stalling. Switched to other starter, started better, but would not hold idle or even take throttle, just like yesterday after the 4 tank cycle. Leaned the LSN 1/8th. Got it moving, but still bad. Three passes, and then leaned LN another 1/8th, 3 passes, getting better and faster than yesterday's HSN attempts, did it one more time, 1/8th and 3 passes. The last two times I adjusted the LSN it showed a lot of mid-range bogging, with a little clearing out at WOT either by rolling on the throttle or jamming it open.

Temps after last LSN adjustment:

Inside da' hole - 160

Outside da' hole - 140

Daytime temp - 70

Do I lean LSN more or should I start to lean HSN to get rid of midrange bogginess. It is clearing out above mid range, but barely. And yes, I know, DON'T TOUCH THE MR NEEDLE!!!
 
First, you need to understand that ONE needle does not correct two problems. Expect it to be a bit boggy since it's still rich for break in. Don't expect to be ripping wheelies and hitting 90mph.
The LSN and the idle screw:
These two will give you a good idle, and the proper idle temp.
The LSN will ONLY affect the low end take off till mid throttle. When this is correct, it will move out from a stop. Anything above that, for faster running is the HSN.
If it's idling and pulling out, but gets boggy with more throttle, you need to lean the HSN at that point.
Once the LSN and idle are good, DO NOT change them. Make only HSN adjustments for WOT.
 
YEs, Rolex, I got that. With your and Corrado's suggestions I leaned out hte LSN. Runs great low end. Still bogs heavy mid but clears out slightly at top. WOT at mid range ends up real boggy.

Idle went up with LSN leaning so I moved that down enough to accomodate the throttle trim (your tip, Rolex.) Got a decent idle and low end performance. Well, out to the garage to try a couple of passes with the HSN in 1/4. I'll give temps, too, when I report back.

Man was the 2.5 R easier. Rolex is a tunign genius, and I thought I was getting pretty good as my 2.5R's are running so good, but this knuckle buster starter motor really is pushing my grey cells to think. But, as Rolex says, move only one needle and one small move, see what it does and take a temp.
 
Keep in mind that you don't make any adjustments till you're at a good running temp. Adjusting it when it's cold will make it run bad when it warms up.
Patience is the key. It's still being broken in, and a lot of these go through "The break in blues."
 
Ok, Rolex, that brings up a good point. I let it idle about 1-1.5 minutes then try to start to move (this is all today) Is this long enough considering it is 70 out right now? After 2-3 passes the results are still the same, but my temps are now 170 in da' hole. I did lean the HSN 1/8 more and it still blows huge amounts of smoke. I know it is a bigger motor than my Revo and T-maxx, but the amount of fuel on my garage floor from the pipe and the smoke trail is really outrageous!
 
OK guys. I am getting there. I have it running pretty decent right now. I leaned the LSN more, reduced the idle some more and tooka full 1/4 turn off the HSN. It has good throttle response for all ranges and still leaving a really heavy trail of smoke. Head temp is 180 inside, 170 outside.

Time to throw it back into hiding. Wifey does not know I have this beast, yet. She will know on 3/11!
 
If it's 70 out, you're at an ideal temp for breaking it in. Check you idle temp without driving the car. That's where you still want about 170.
After running it, you want to see around 260 at the very most. Right now, go for about 240 or so during this period.
It sounds like you still can lean out you HSN some more. Keep at it.
If, after several WOT runs, it's still way down in temp, lean the HSN a little more.
Don't do more than about 1/8 turn at a time.
Check the temps often, and adjust accordingly. Remember, we want an improvement in performance, but we're still not shooting for maximum. It still needs to break in some more.
 
Hey Rolex,
My Werks .26 had a gallon run thru it before I got it. I was running it at the track and had great all around power @ about 218-225. The only adjustment I had to make was a slight richening of the LSN. I decided that since it had more power than I needed I would leave it at that setup, I ran at least 6 tanks of gas thru it at the track. I figure that I will now begin to adjust the HSN for performance using 3 methods of observation. 1: sound, listening how it sounds as it accelerates from mid to WOT. 2: sight, looking for a medium trail of smoke. 3: temp, looking for optimum performance around 250-260. For LSN I gauge how well it clears out when I nail the throttle holding it off the ground, wether it bogs or clears out, then I use the pinch test, looking for about 3-5 seconds before it begins to die.
I figured that this motor was adequately broke in when I got it, if not, it is now!
 
Roger that! High speed,low drag!
 
That's why it often takes 2 days to get someone tuned over the internet. Time and schedule differences, plus the fact that I can't see it, hear it, or touch it. A day or two to tune it here, two minutes to a half hour at most at the track.
When someone follows me, then lets me know what changes, I'll stay with it till it's right.
Revo Rancher, hang in there, we're close.
 
thanks for taking over Rolex. i was busy all today, and I'm even at work right now. REVO, it sounds as if you could still stand to lean out the LSN a hair. we are aiming for about 80% of the performance potential of your engine for the first gallon. after that you can tune to 95% of its potential and not have to worry about durability. take your time and listen to rolex, he knows whats up. :thumbup:
 
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