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

由于多(duo)缸發動機熄火時(shi)往往停轉(zhuan)在(zai)壓縮力最(zui)大的那(nei)個缸，使得每(mei)次(ci)起(qi)動時(shi)飛輪齒(chi)圈受撞擊的部位大致相同，久(jiu)之便使該(gai)處(chu)齒(chi)圈切入面變形。遇(yu)此情況，可(ke)(ke)將飛輪齒(chi)圈轉(zhuan)一(yi)個角度或前、后(hou)翻轉(zhuan)后(hou)重(zhong)新(xin)裝入，在(zai)正(zheng)常(chang)情況下，如(ru)果一(yi)次(ci)不能(neng)起(qi)動，則必須等齒(chi)輪退回(hui)到原(yuan)來靜止的位置(zhi)后(hou)，方可(ke)(ke)作第二(er)次(ci)的起(qi)動。

2.間隙過大

齒(chi)(chi)輪與(yu)(yu)齒(chi)(chi)圈(quan)的軸向距離應該保持(chi)2.5-5毫米。這(zhe)樣，當主電(dian)路(lu)接通(tong)后，起動(dong)(dong)(dong)(dong)(dong)機(ji)齒(chi)(chi)輪與(yu)(yu)飛(fei)輪齒(chi)(chi)圈(quan)尚未(wei)嚙合(he)(he)即已高速(su)旋(xuan)轉，兩者接觸時(shi)自(zi)然(ran)會因撞擊而(er)發出(chu)響聲，且兩者無法嚙合(he)(he)，發動(dong)(dong)(dong)(dong)(dong)機(ji)也(ye)就不能起動(dong)(dong)(dong)(dong)(dong)。遇此(ci)故障(zhang)，可采取將起動(dong)(dong)(dong)(dong)(dong)機(ji)電(dian)磁開關(guan)的靜、動(dong)(dong)(dong)(dong)(dong)觸點間(jian)隙(xi)調大；在電(dian)磁開關(guan)與(yu)(yu)起動(dong)(dong)(dong)(dong)(dong)機(ji)后殼間(jian)加墊；消除(chu)起動(dong)(dong)(dong)(dong)(dong)機(ji)撥叉中部(bu)支承銷的多余(yu)間(jian)隙(xi)；更(geng)換(huan)撥叉上磨損變小的滑塊或(huo)滑輪；往飛(fei)輪上裝入齒(chi)(chi)圈(quan)時(shi)，勿將齒(chi)(chi)圈(quan)壓到飛(fei)輪底部(bu)，留2-3毫米間(jian)隙(xi)或(huo)選用加厚齒(chi)(chi)圈(quan)等方(fang)法，予以排(pai)除(chu)。另外，市場上銷售的起動(dong)(dong)(dong)(dong)(dong)機(ji)驅動(dong)(dong)(dong)(dong)(dong)齒(chi)(chi)輪，有的總體長度不符合(he)(he)標準，也(ye)有些(xie)不正規廠生產的飛(fei)輪及齒(chi)(chi)圈(quan)高度不符合(he)(he)標準，都容易造(zao)成(cheng)這(zhe)種現象(xiang)，購買時(shi)要格外注意(yi)不要貪圖便宜而(er)造(zao)成(cheng)更(geng)大的損失(shi) 。