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標題: .12 Engine sometimes stall out (die) when apply brake [打印本頁]

作者: TheWolf 時間: 2012-6-3 22:19
標題: .12 Engine sometimes stall out (die) when apply brake
Hi,

My .12 Engine touring car runs ok with responsive initial acceleration and healthy smoke. However, it's quite easy to stall out when applying hard brake. Any hints? Thanks.

作者: vincentwow1450 時間: 2012-6-3 22:29
what engine are you using?
try a new glow plug

作者: bear_cat_x 時間: 2012-6-3 23:57
回復 TheWolf 的帖子

You can tighten the idling screw until no die-out is observed when applying brake

作者: justinwan 時間: 2012-6-4 01:19
check yr clutch. May be yr clutch is angaged when u apply brake. means u also stop the crankshaft while u are braking.

作者: beebone 時間: 2012-6-4 03:39
本帖最後由 beebone 於 2012-6-4 03:39 編輯

TheWolf 發表於 2012-6-3 22:19

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Hi,

My .12 Engine touring car runs ok with responsive initial acceleration and healthy smoke. H ...

Assume ur brake works fine.
Engine stalls when brake, idle too low.
Car won't stop, idle too high.

作者: TheWolf 時間: 2012-6-4 08:13
Thanks, I think it's my idle speed too high as the clutch seems marginally engaging the engine after recent break in/tuning. Will try to tighten the idle speed needle a bit to slow down idle rpm. Thank you.

作者: beebone 時間: 2012-6-4 10:26

TheWolf 發表於 2012-6-4 08:13

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Thanks, I think it's my idle speed too high as the clutch seems marginally engaging the engine after ...

Serveral things to check,

Check the clutch first, if engage in high rpm (u can hear it, its very high pitch), lose the preload spring or re-position bell distance.

Check the idle screw, you can set the idle w/o stall first when cold, then drive and test how long the idle can last, over 10 sec should be fine.

Check the engine bearing (if your engine ran certain mileage)

作者: TheWolf 時間: 2012-6-4 19:17
Thanks beebone,

I'll check the idle screw first, as my HPI T3.0 .18 just about finishing the break in process, around 6 tanks, the idle rpm keep increasing as fine tuning the HSN and LSN but didn't address the idle needle for quite a while. Time to lowering the idle rpm...will try thanks.

作者: TheWolf 時間: 2012-6-4 23:54
Quick actions taken tonight:
1. Found that my transmitter neutral throttle position is a bit bias forward/open and re-adjusted throttle trim to re-align it with idle speed needle setting, i.e. lowering the idle rpm.
2. Idle ok but stall whenever applying light or hard throttle, then tighten up the HSN a bit.
3. Seems working fine now, slower idle rpm, a bit slower at initial acceleration but very good response then. Keep running even applying hard brake now.
4. Need more testing in more open area later on.

Root cause: initial idle speed a bit high due to slightly shifted forward neutral throttle position. Thanks.

作者: beebone 時間: 2012-6-5 06:44

TheWolf 發表於 2012-6-4 19:17

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Thanks beebone,

I'll check the idle screw first, as my HPI T3.0 .18 just about finishing the brea ...

Its normal, when gradually lean the LSN, the idle will goes up. The rule of thumb is, lean the LSN every 15 min and try to blip the throttle (about 40% throttle) for 2 sec, then listen how long can the engine idle. when the idle continue stay high, then lower the idle.

作者: beebone 時間: 2012-6-5 06:50
回復 TheWolf 的帖子

Seem u r not in HK.
Ok, neutral position is very important. Easy way to do is, turn the radio on and put on neutral position. Then adjust the throttle stopper first, then adjust the spring stopper. Beware the spring can't too tight, and brake return position won't affect the close position of throttle slide

作者: TheWolf 時間: 2012-6-5 06:56
Hi, you mean 'clip' the throttle, right? I hope I got what you meant and will try, thanks.

作者: beebone 時間: 2012-6-5 10:34

TheWolf 發表於 2012-6-5 06:56

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Hi, you mean 'clip' the throttle, right? I hope I got what you meant and will try, thanks.

hold 50% throttle for 2 sec

作者: TheWolf 時間: 2012-6-6 22:38
I'm in HK, will try the 2sec 50%throttle rule this weekend fine tuning it. Thx

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