EA82 lifters - intimate knowledge request
Posted: Thu Jul 17, 2008 12:43 pm
does anyone have an intimate knowledge of the hydraulic lifters / lash adjusters of the EA82 and EA82T ?
some may know I am midway in renewing my lifters in chasing down an intermittent and characteristic miss on cylinder #2 that smacks of lifter pump up as described in here somewhere in relation to service short cuts READ: WRONG OIL GRADE (not the heading of relevant article either)
http://www.fueltech.com.au/trade_vehicletips.html
I have found both of #2 to be rock hard on removal. The new ones without oil have some allowable depression. Possibly the removed ones still with oil won't allow budge. The manuel talks about no more than 0.5mm depression with oil. I am not sure if I have found the problem gone looking for. Valve springs do feel really strong for those that say weak valve springs. My head guys dismiss weak valve springs due to the characteristics of the miss
looking at the head design and the lifter it looks that the oil pressure arrives via a common gallery, surround the 'waist' of the lifter and enters via the hole in the upper side of the 'waist' or lesser diameter section. It enters the piston chamber and below where a spring sits and below that a ball bearing valve to a chamber below.
There doews not appear to be an exit for the oil , other than the clearances betweeen the piston and its bore to the outside world where the cam and rocker is. Also between the lifter and its bore in the head.
So, does oil actually flow through the lifter or just supply it with pressure to assist the built in spring ?
I suppose I should include some photos of a dismantled one for all to see
IF ONLY I COULD POST BIGGER PHOTOS THAN IMAGESHACK APPEARS TO ALLOW ME
some may know I am midway in renewing my lifters in chasing down an intermittent and characteristic miss on cylinder #2 that smacks of lifter pump up as described in here somewhere in relation to service short cuts READ: WRONG OIL GRADE (not the heading of relevant article either)
http://www.fueltech.com.au/trade_vehicletips.html
I have found both of #2 to be rock hard on removal. The new ones without oil have some allowable depression. Possibly the removed ones still with oil won't allow budge. The manuel talks about no more than 0.5mm depression with oil. I am not sure if I have found the problem gone looking for. Valve springs do feel really strong for those that say weak valve springs. My head guys dismiss weak valve springs due to the characteristics of the miss
looking at the head design and the lifter it looks that the oil pressure arrives via a common gallery, surround the 'waist' of the lifter and enters via the hole in the upper side of the 'waist' or lesser diameter section. It enters the piston chamber and below where a spring sits and below that a ball bearing valve to a chamber below.
There doews not appear to be an exit for the oil , other than the clearances betweeen the piston and its bore to the outside world where the cam and rocker is. Also between the lifter and its bore in the head.
So, does oil actually flow through the lifter or just supply it with pressure to assist the built in spring ?
I suppose I should include some photos of a dismantled one for all to see
IF ONLY I COULD POST BIGGER PHOTOS THAN IMAGESHACK APPEARS TO ALLOW ME