lifter ? stuck or collapsed?

[starsnstripers]

Getting ready to fire up the 68 L6 250. had the rod covers and valve cover off and was installing the dist. and timing it when i noticed when rotating the motor over by hand one lifter is stuck down a bit alot of play at the rocker. there hyd. lifters and the motor has been sitting. will it pump up when starting and oil pressure or is it collapsed and need a new one or should i remove it take it appart clean and inspect? the come out easy, I dont think its so loose that if i started it that it will throw the rod. comments?

 

[flabum]

Re: lifter ? stuck or collapsed?

Are you sure it's not the valve not comming all the way up?

 

[Lakester]

Re: lifter ? stuck or collapsed?

hello-

the L6 250 is basically a V8 inline, well the v8 is an inline bent... lol

a) check the tops of all lifters that they come past the top of lifter bore more or less the same. should. if not, suggest a flat cam.

b) it would be hard to 'see' a lifter not coming up enuff with lifte covers on, unless u could carefully monitor the push rod travel. and this would take a dial indicator to do it right.

c) the lifter cant collaps more than about .100" or other words, it wont pump up. the slop u say is at the rocker suggests to me that the rocker arm stud nut is not properly adjusted.

d) if it were mine: since it has been sitting, i would remove all lifters, ONE lifter hole at a time. take apart. this is about only way to get rid of all oil in it in short fashion. clean and blow dry. reassemble. now take a padded phillips sd end and push down on lifter cup seat. it should move about .100".

e) do this to all lifters ONE lifter bore at a time. then replace each one hole at a time. add some cam lube to bottom of lifter. DO NOT mix them up.

f) then set each cyl, by firing order... starting with #1 and get on TDC with valves closed. draw down the rocker stud nut, to -0- lash, but push rod still rotates tween ur fingers. now push down on push rod and note travel. about .100". so as book says, adjust rocker arm nut down about 2 turns or so. so do that. now push again... should be about 1/2" the travel dist as befoe. or... .050". this puts lifter's piddle valve in middle of travel stroke. just where u want it.

g) do all 6 holes for each valve. lifter must be clean and dry.

h) then hand prime engine's oil pump until oil comes out of push rod rocker cup hole. dont rotate engine. turn oil pump. ez to do. use drill and shaft that fits pump slot.

i) all 12 rocker arms must... bleed oil. then when she starts, aside from a shake or two as she gets her act together... she will run quiet with no lifter noise. works every time!!!

sounds like ur lifter bled down over time, and rocker arm nut is out of adjustment.

let us know how she runs...

regards,

lakester

 

[Lakester]

Re: lifter ? stuck or collapsed?

also:

see my post:

http://forums.iboats.com/showthread.php?t=230711

regards,

lakester

 

[starsnstripers]

Re: lifter ? stuck or collapsed?

The rocker nuts havent been touched since the motor ran. It's rebuilt but has a few hours on it. I have the side covers off and i can pysically see that one lifter. The cup were the push rod sits is lower that it should be and lower than the rest of the lifters. And thats a good idea priming the pump i'll do that before i start it. Do you think that lifter will pump up or it's collapsed?

 

[rodbolt]

Re: lifter ? stuck or collapsed?

like it was said, prime the oil system with a drill and see.
its not uncommon to hve a lifter plunger leak down due to valve spring pressure when sitting. however the plunger should come bck to within about .05" of the retainer with no load on it( valve closed) I think the book says 1 turn down from zero lash.
its possible to disasemble and clean the lifter but I usully replace them. there is nothing "marine" about the lifter and you dont need anti-pump up ones due to the low operating RPM.
do not mix and match the plunger parts to the lifter bodies nor mix and match lifter bodies to cam lobes.

remember you will always have a fw cam lobes that are trying to open a valve with the crank at any position and over time the lifter will bleed off and collapse. doesnt always men the lifter is bad as long as the plunger is free to move.

 

[starsnstripers]

Re: lifter ? stuck or collapsed?

Thanks rod and lake I'll prime it up and see what happens if it dont come up i'll take it out and inspect/clean it. I didnt want to ruin a rod or something tring to start it with the lifter loose. Have a good holiday.