齒軸與齒圈起動機起動時驅動齒輪與發動機飛輪齒圈發出撞擊的空轉聲，其原因有二：變形和間隙過大。

1.變形

由于(yu)多缸發動機熄火時(shi)往往停轉(zhuan)在(zai)壓縮力最大的(de)(de)那個缸，使(shi)得(de)每次起(qi)動時(shi)飛輪(lun)齒圈受(shou)撞擊(ji)的(de)(de)部位大致(zhi)相(xiang)同，久之便使(shi)該(gai)處(chu)齒圈切入(ru)面變形。遇此情(qing)況，可將飛輪(lun)齒圈轉(zhuan)一個角(jiao)度或前(qian)、后(hou)翻轉(zhuan)后(hou)重新裝入(ru)，在(zai)正常(chang)情(qing)況下，如果一次不能起(qi)動，則必須(xu)等(deng)齒輪(lun)退回到原來靜止的(de)(de)位置(zhi)后(hou)，方可作第(di)二次的(de)(de)起(qi)動。

2.間(jian)隙過大(da)

齒(chi)(chi)(chi)輪(lun)(lun)與(yu)齒(chi)(chi)(chi)圈(quan)(quan)的軸向距離應(ying)該保(bao)持2.5-5毫(hao)米。這(zhe)樣，當主(zhu)電(dian)(dian)(dian)路(lu)接通后，起動(dong)(dong)(dong)機(ji)(ji)齒(chi)(chi)(chi)輪(lun)(lun)與(yu)飛輪(lun)(lun)齒(chi)(chi)(chi)圈(quan)(quan)尚未嚙合即(ji)已高(gao)速(su)旋轉，兩(liang)者(zhe)接觸時(shi)(shi)自然會因撞擊而發(fa)(fa)出響聲，且兩(liang)者(zhe)無法嚙合，發(fa)(fa)動(dong)(dong)(dong)機(ji)(ji)也就(jiu)不(bu)能起動(dong)(dong)(dong)。遇(yu)此故障，可采取將起動(dong)(dong)(dong)機(ji)(ji)電(dian)(dian)(dian)磁(ci)開(kai)關(guan)(guan)的靜(jing)、動(dong)(dong)(dong)觸點(dian)間(jian)隙調大；在電(dian)(dian)(dian)磁(ci)開(kai)關(guan)(guan)與(yu)起動(dong)(dong)(dong)機(ji)(ji)后殼間(jian)加墊；消除(chu)起動(dong)(dong)(dong)機(ji)(ji)撥叉中部支(zhi)承(cheng)銷的多余(yu)間(jian)隙；更換撥叉上(shang)(shang)磨損(sun)變小的滑塊或滑輪(lun)(lun)；往飛輪(lun)(lun)上(shang)(shang)裝入齒(chi)(chi)(chi)圈(quan)(quan)時(shi)(shi)，勿(wu)將齒(chi)(chi)(chi)圈(quan)(quan)壓到飛輪(lun)(lun)底部，留2-3毫(hao)米間(jian)隙或選用加厚齒(chi)(chi)(chi)圈(quan)(quan)等方法，予以排除(chu)。另外，市(shi)場(chang)上(shang)(shang)銷售的起動(dong)(dong)(dong)機(ji)(ji)驅動(dong)(dong)(dong)齒(chi)(chi)(chi)輪(lun)(lun)，有的總體長(chang)度不(bu)符(fu)(fu)合標準，也有些(xie)不(bu)正規廠生(sheng)產的飛輪(lun)(lun)及(ji)齒(chi)(chi)(chi)圈(quan)(quan)高(gao)度不(bu)符(fu)(fu)合標準，都容易造成這(zhe)種(zhong)現象，購買時(shi)(shi)要格外注意不(bu)要貪圖(tu)便宜而造成更大的損(sun)失(shi) 。