卡特挖掘機維修
一臺卡特320B型(xing)挖掘機(ji)，在(zai)長途運輸途中(zhong)不(bu)慎(shen)側(ce)翻于公(gong)路(lu)旁，用(yong)起(qi)重(zhong)機(ji)將控制機(ji)吊起(qi)后(hou)，發(fa)(fa)(fa)現(xian)(xian)挖掘機(ji)僅發(fa)(fa)(fa)動(dong)(dong)(dong)(dong)(dong)機(ji)一側(ce)的護殼破壞，而其余部分(fen)完好(hao)無損。駕駛員檢查(cha)發(fa)(fa)(fa)現(xian)(xian)，機(ji)油(you)(you)、柴油(you)(you)和冷卻水都不(bu)同程度地流失(shi)。分(fen)別添加了機(ji)油(you)(you)、柴油(you)(you)和水后(hou)啟動(dong)(dong)(dong)(dong)(dong)發(fa)(fa)(fa)動(dong)(dong)(dong)(dong)(dong)機(ji)時，只(zhi)聽到(dao)起(qi)動(dong)(dong)(dong)(dong)(dong)機(ji)與發(fa)(fa)(fa)動(dong)(dong)(dong)(dong)(dong)機(ji)飛輪有強(qiang)烈的撞擊聲。同時觀(guan)察(cha)到(dao)發(fa)(fa)(fa)動(dong)(dong)(dong)(dong)(dong)機(ji)風扇(shan)葉片只(zhi)是(shi)略微轉動(dong)(dong)(dong)(dong)(dong)了一下(xia)，再次啟動(dong)(dong)(dong)(dong)(dong)時故(gu)障(zhang)依(yi)舊， 為(wei)查(cha)清“為(wei)什(shen)么(me)起(qi)動(dong)(dong)(dong)(dong)(dong)機(ji)不(bu)能帶動(dong)(dong)(dong)(dong)(dong)發(fa)(fa)(fa)動(dong)(dong)(dong)(dong)(dong)機(ji)轉動(dong)(dong)(dong)(dong)(dong)”，首先。檢查(cha)了是(shi)電器部分(fen)還(huan)是(shi)電動(dong)(dong)(dong)(dong)(dong)機(ji)部分(fen)有故(gu)障(zhang)。用(yong)扳(ban)手在(zai)發(fa)(fa)(fa)動(dong)(dong)(dong)(dong)(dong)曲軸皮帶輪上(shang)來回扳(ban)動(dong)(dong)(dong)(dong)(dong)螺栓時，感(gan)覺很(hen)費力且(qie)皮帶輪只(zhi)能來回轉動(dong)(dong)(dong)(dong)(dong)很(hen)小個角度，說(shuo)明起(qi)動(dong)(dong)(dong)(dong)(dong)機(ji)不(bu)能帶動(dong)(dong)(dong)(dong)(dong)發(fa)(fa)(fa)動(dong)(dong)(dong)(dong)(dong)機(ji)轉動(dong)(dong)(dong)(dong)(dong)是(shi)發(fa)(fa)(fa)動(dong)(dong)(dong)(dong)(dong)機(ji)阻力過大造成的。
不(bu)(bu)是(shi)(shi)電器(qi)部分(fen)的(de)(de)(de)故障(zhang)，分(fen)析認為(wei)。挖(wa)(wa)掘機(ji)置于(yu)(yu)拖車上預備(bei)長途運輸(shu)前(qian)，發動(dong)(dong)(dong)機(ji)的(de)(de)(de)技術狀(zhuang)態(tai)是(shi)(shi)正常的(de)(de)(de)，故不(bu)(bu)可能是(shi)(shi)正時系統、連桿(gan)配氣機(ji)構卡死以及曲(qu)軸(zhou)抱死；出現起(qi)動(dong)(dong)(dong)機(ji)不(bu)(bu)能帶動(dong)(dong)(dong)發動(dong)(dong)(dong)機(ji)轉動(dong)(dong)(dong)是(shi)(shi)發生在挖(wa)(wa)掘機(ji)側(ce)(ce)翻后，挖(wa)(wa)掘機(ji)側(ce)(ce)翻時發動(dong)(dong)(dong)機(ji)的(de)(de)(de)I缸(gang)高(gao)于(yu)(yu)VI缸(gang)位(wei)置、油(you)底殼(ke)高(gao)于(yu)(yu)缸(gang)蓋位(wei)置，發動(dong)(dong)(dong)機(ji)處在這種狀(zhuang)態(tai)下油(you)底殼(ke)內的(de)(de)(de)機(ji)油(you)就(jiu)會慢(man)慢(man)地從缸(gang)壁間隙處流(liu)入(ru)燃燒室；由于(yu)(yu)VI缸(gang)所處位(wei)置最低，I缸(gang)所處位(wei)置最高(gao)，因而機(ji)油(you)流(liu)入(ru)燃油(you)室的(de)(de)(de)可能最大的(de)(de)(de)是(shi)(shi)VI缸(gang)，依次是(shi)(shi)V缸(gang)、IV缸(gang)，可能性最小的(de)(de)(de)是(shi)(shi)I缸(gang)，于(yu)(yu)是(shi)(shi)拆下IV、V、VI缸(gang)的(de)(de)(de)氣門(men)室罩，用一(yi)字(zi)形改錐插入(ru)VI缸(gang)進、排(pai)氣門(men)的(de)(de)(de)間隙處。目的(de)(de)(de)是(shi)(shi)使VI缸(gang)進、排(pai)氣門(men)一(yi)直處于(yu)(yu)打開狀(zhuang)態(tai)。
此時(shi)(shi)用(yong)扳(ban)(ban)(ban)手(shou)來回扳(ban)(ban)(ban)動(dong)(dong)(dong)曲輪(lun)(lun)皮帶輪(lun)(lun)，感(gan)到曲軸轉(zhuan)動(dong)(dong)(dong)角度比(bi)以前略(lve)為大(da)一(yi)些(xie)，用(yong)同樣的方法，使V缸進(jin)(jin)、排(pai)氣(qi)門(men)(men)處(chu)(chu)(chu)于(yu)(yu)(yu)打開狀態(tai)(tai)，轉(zhuan)動(dong)(dong)(dong)曲軸皮帶輪(lun)(lun)時(shi)(shi)，感(gan)到曲軸能(neng)(neng)轉(zhuan)動(dong)(dong)(dong)的角度又要(yao)大(da)一(yi)些(xie)；使IV缸進(jin)(jin)、排(pai)氣(qi)門(men)(men)處(chu)(chu)(chu)于(yu)(yu)(yu)打開狀態(tai)(tai)，曲軸就完(wan)全(quan)能(neng)(neng)轉(zhuan)動(dong)(dong)(dong)360°。由此證明，是發動(dong)(dong)(dong)機(ji)(ji)油(you)(you)底殼內機(ji)(ji)油(you)(you)通過(guo)(guo)(guo)缸壁間隙(xi)(xi)流(liu)進(jin)(jin)了燃燒(shao)室，由于(yu)(yu)(yu)大(da)量(liang)機(ji)(ji)油(you)(you)流(liu)入燃燒(shao)室，起動(dong)(dong)(dong)機(ji)(ji)（或用(yong)扳(ban)(ban)(ban)手(shou)扳(ban)(ban)(ban)動(dong)(dong)(dong)曲軸皮帶輪(lun)(lun)）使曲軸轉(zhuan)動(dong)(dong)(dong)時(shi)(shi)，在(zai)活塞上行的過(guo)(guo)(guo)程中壓縮比(bi)過(guo)(guo)(guo)高（各處(chu)(chu)(chu)間隙(xi)(xi)均(jun)處(chu)(chu)(chu)于(yu)(yu)(yu)完(wan)全(quan)密封狀態(tai)(tai)），曲軸轉(zhuan)動(dong)(dong)(dong)阻力(li)過(guo)(guo)(guo)大(da)，故(gu)表現出起動(dong)(dong)(dong)機(ji)(ji)不能(neng)(neng)帶動(dong)(dong)(dong)發動(dong)(dong)(dong)機(ji)(ji)轉(zhuan)動(dong)(dong)(dong)，故(gu)障(zhang)原因找到后，決(jue)定改用(yong)1mm塞尺插入IV、V、VI缸進(jin)(jin)、排(pai)氣(qi)門(men)(men)間隙(xi)(xi)處(chu)(chu)(chu)以代替(ti)一(yi)字形改錐（因一(yi)字形改錐過(guo)(guo)(guo)厚）。
以免(mian)氣門(men)壓(ya)下過多而頂壞活塞(sai)(sai)(sai)，但試機(ji)(ji)時(shi)起動(dong)(dong)機(ji)(ji)同樣不能啟動(dong)(dong)，于是將塞(sai)(sai)(sai)尺(chi)的厚度由1mm增加到15mm，再次啟動(dong)(dong)時(shi)發(fa)動(dong)(dong)機(ji)(ji)能順利(li)啟動(dong)(dong)，并(bing)從排(pai)氣管(guan)排(pai)出(chu)了(le)大(da)量(liang)機(ji)(ji)油(you)，這時(shi)，有(you)兩缸(gang)的塞(sai)(sai)(sai)尺(chi)從氣門(men)間隙(xi)處滑出(chu)。而發(fa)動(dong)(dong)機(ji)(ji)立即被憋(bie)而熄(xi)火；重(zhong)新插入塞(sai)(sai)(sai)尺(chi)，再次順利(li)啟動(dong)(dong)發(fa)動(dong)(dong)機(ji)(ji)，并(bing)怠速運轉了(le)約1min。但帛(bo)出(chu)IV缸(gang)的塞(sai)(sai)(sai)尺(chi)后，發(fa)動(dong)(dong)機(ji)(ji)又被憋(bie)熄(xi)火，說明燃燒室內機(ji)(ji)油(you)還很多，于是又重(zhong)新插入塞(sai)(sai)(sai)尺(chi)，再次啟動(dong)(dong)發(fa)動(dong)(dong)機(ji)(ji)，并(bing)怠速運轉了(le)5min，估計燃燒室內機(ji)(ji)油(you)已排(pai)盡后，相繼(ji)抽(chou)出(chu)IV缸(gang)和V缸(gang)的塞(sai)(sai)(sai)尺(chi)，發(fa)動(dong)(dong)機(ji)(ji)都能正常(chang)運轉，最后抽(chou)出(chu)了(le)IV缸(gang)塞(sai)(sai)(sai)尺(chi)，發(fa)動(dong)(dong)機(ji)(ji)的運轉也正常(chang)，說明故障已被徹底排(pai)除。
不(bu)(bu)是(shi)(shi)電器(qi)部分(fen)的(de)(de)(de)故障(zhang)，分(fen)析認為(wei)。挖(wa)(wa)掘機(ji)置于(yu)(yu)拖車上預備(bei)長途運輸(shu)前(qian)，發動(dong)(dong)(dong)機(ji)的(de)(de)(de)技術狀(zhuang)態(tai)是(shi)(shi)正常的(de)(de)(de)，故不(bu)(bu)可能是(shi)(shi)正時系統、連桿(gan)配氣機(ji)構卡死以及曲(qu)軸(zhou)抱死；出現起(qi)動(dong)(dong)(dong)機(ji)不(bu)(bu)能帶動(dong)(dong)(dong)發動(dong)(dong)(dong)機(ji)轉動(dong)(dong)(dong)是(shi)(shi)發生在挖(wa)(wa)掘機(ji)側(ce)(ce)翻后，挖(wa)(wa)掘機(ji)側(ce)(ce)翻時發動(dong)(dong)(dong)機(ji)的(de)(de)(de)I缸(gang)高(gao)于(yu)(yu)VI缸(gang)位(wei)置、油(you)底殼(ke)高(gao)于(yu)(yu)缸(gang)蓋位(wei)置，發動(dong)(dong)(dong)機(ji)處在這種狀(zhuang)態(tai)下油(you)底殼(ke)內的(de)(de)(de)機(ji)油(you)就(jiu)會慢(man)慢(man)地從缸(gang)壁間隙處流(liu)入(ru)燃燒室；由于(yu)(yu)VI缸(gang)所處位(wei)置最低，I缸(gang)所處位(wei)置最高(gao)，因而機(ji)油(you)流(liu)入(ru)燃油(you)室的(de)(de)(de)可能最大的(de)(de)(de)是(shi)(shi)VI缸(gang)，依次是(shi)(shi)V缸(gang)、IV缸(gang)，可能性最小的(de)(de)(de)是(shi)(shi)I缸(gang)，于(yu)(yu)是(shi)(shi)拆下IV、V、VI缸(gang)的(de)(de)(de)氣門(men)室罩，用一(yi)字(zi)形改錐插入(ru)VI缸(gang)進、排(pai)氣門(men)的(de)(de)(de)間隙處。目的(de)(de)(de)是(shi)(shi)使VI缸(gang)進、排(pai)氣門(men)一(yi)直處于(yu)(yu)打開狀(zhuang)態(tai)。
此時(shi)(shi)用(yong)扳(ban)(ban)(ban)手(shou)來回扳(ban)(ban)(ban)動(dong)(dong)(dong)曲輪(lun)(lun)皮帶輪(lun)(lun)，感(gan)到曲軸轉(zhuan)動(dong)(dong)(dong)角度比(bi)以前略(lve)為大(da)一(yi)些(xie)，用(yong)同樣的方法，使V缸進(jin)(jin)、排(pai)氣(qi)門(men)(men)處(chu)(chu)(chu)于(yu)(yu)(yu)打開狀態(tai)(tai)，轉(zhuan)動(dong)(dong)(dong)曲軸皮帶輪(lun)(lun)時(shi)(shi)，感(gan)到曲軸能(neng)(neng)轉(zhuan)動(dong)(dong)(dong)的角度又要(yao)大(da)一(yi)些(xie)；使IV缸進(jin)(jin)、排(pai)氣(qi)門(men)(men)處(chu)(chu)(chu)于(yu)(yu)(yu)打開狀態(tai)(tai)，曲軸就完(wan)全(quan)能(neng)(neng)轉(zhuan)動(dong)(dong)(dong)360°。由此證明，是發動(dong)(dong)(dong)機(ji)(ji)油(you)(you)底殼內機(ji)(ji)油(you)(you)通過(guo)(guo)(guo)缸壁間隙(xi)(xi)流(liu)進(jin)(jin)了燃燒(shao)室，由于(yu)(yu)(yu)大(da)量(liang)機(ji)(ji)油(you)(you)流(liu)入燃燒(shao)室，起動(dong)(dong)(dong)機(ji)(ji)（或用(yong)扳(ban)(ban)(ban)手(shou)扳(ban)(ban)(ban)動(dong)(dong)(dong)曲軸皮帶輪(lun)(lun)）使曲軸轉(zhuan)動(dong)(dong)(dong)時(shi)(shi)，在(zai)活塞上行的過(guo)(guo)(guo)程中壓縮比(bi)過(guo)(guo)(guo)高（各處(chu)(chu)(chu)間隙(xi)(xi)均(jun)處(chu)(chu)(chu)于(yu)(yu)(yu)完(wan)全(quan)密封狀態(tai)(tai)），曲軸轉(zhuan)動(dong)(dong)(dong)阻力(li)過(guo)(guo)(guo)大(da)，故(gu)表現出起動(dong)(dong)(dong)機(ji)(ji)不能(neng)(neng)帶動(dong)(dong)(dong)發動(dong)(dong)(dong)機(ji)(ji)轉(zhuan)動(dong)(dong)(dong)，故(gu)障(zhang)原因找到后，決(jue)定改用(yong)1mm塞尺插入IV、V、VI缸進(jin)(jin)、排(pai)氣(qi)門(men)(men)間隙(xi)(xi)處(chu)(chu)(chu)以代替(ti)一(yi)字形改錐（因一(yi)字形改錐過(guo)(guo)(guo)厚）。
以免(mian)氣門(men)壓(ya)下過多而頂壞活塞(sai)(sai)(sai)，但試機(ji)(ji)時(shi)起動(dong)(dong)機(ji)(ji)同樣不能啟動(dong)(dong)，于是將塞(sai)(sai)(sai)尺(chi)的厚度由1mm增加到15mm，再次啟動(dong)(dong)時(shi)發(fa)動(dong)(dong)機(ji)(ji)能順利(li)啟動(dong)(dong)，并(bing)從排(pai)氣管(guan)排(pai)出(chu)了(le)大(da)量(liang)機(ji)(ji)油(you)，這時(shi)，有(you)兩缸(gang)的塞(sai)(sai)(sai)尺(chi)從氣門(men)間隙(xi)處滑出(chu)。而發(fa)動(dong)(dong)機(ji)(ji)立即被憋(bie)而熄(xi)火；重(zhong)新插入塞(sai)(sai)(sai)尺(chi)，再次順利(li)啟動(dong)(dong)發(fa)動(dong)(dong)機(ji)(ji)，并(bing)怠速運轉了(le)約1min。但帛(bo)出(chu)IV缸(gang)的塞(sai)(sai)(sai)尺(chi)后，發(fa)動(dong)(dong)機(ji)(ji)又被憋(bie)熄(xi)火，說明燃燒室內機(ji)(ji)油(you)還很多，于是又重(zhong)新插入塞(sai)(sai)(sai)尺(chi)，再次啟動(dong)(dong)發(fa)動(dong)(dong)機(ji)(ji)，并(bing)怠速運轉了(le)5min，估計燃燒室內機(ji)(ji)油(you)已排(pai)盡后，相繼(ji)抽(chou)出(chu)IV缸(gang)和V缸(gang)的塞(sai)(sai)(sai)尺(chi)，發(fa)動(dong)(dong)機(ji)(ji)都能正常(chang)運轉，最后抽(chou)出(chu)了(le)IV缸(gang)塞(sai)(sai)(sai)尺(chi)，發(fa)動(dong)(dong)機(ji)(ji)的運轉也正常(chang)，說明故障已被徹底排(pai)除。
