OIL PRESSURE and FLAT LIFTER-603.960 - PeachParts Mercedes-Benz Forum

markg612 · #1 01-12-2008, 11:06 AM

Anyone had an issue with maintaining steady oil pressure with a lifter that is completely flat at normal operating temps?

Oil pressure is smooth and normal until normal temps are reached and then the pressure pulses in sync with the lifter tick between 1.1-1.9 bar. This is an idle issue, but, the lifter noise of the one lifter can be heard even as engine rpm rise. 2, 3 or 4K rpm the lifter is still flat(ticking). Side note, the lifter is flat enough to cause a slight miss in the exhaust pulse.

Thoughts?

Hatterasguy · #2 01-12-2008, 11:12 AM

A dead lifter on a 603 wouldn't suprise me, they are very easy to replace.

But it sounds like you have other problems, first I'd hook a manual guage up and confirm what the oil pressure is doing.

Mustang_man298 · #3 01-12-2008, 12:49 PM

I would get that lifter fixed asap if it's that bad, running it like that will cause damage to the cam and valve stem/rocker, as it is hammering the snot out of it right now with that kind of slop in it, which will flatten a cam lobe fast and mushroom a valve stem.

PanzerSD · #4 01-13-2008, 05:47 AM

Lifter? I thought these were all OHC engines?

t walgamuth · #5 01-13-2008, 07:40 AM

Right. it is properly called a hydraulic lash adjuster.

for the OP....what kind of oil you using? These lash adjusters are very oil sensitive and will stick if the wrong oil is used.

Tom W

markg612 · #6 01-13-2008, 10:36 AM

Synthetic 5W40 in Minnesota--I have not one but 2 flat lifters after an 0W40 Mobile one disaster followed by a new oil pump. Flow is good at idle, but the pressure fluctuates with the flat lifter ticking.

C Sean Watts · #7 01-13-2008, 11:40 AM

can be from bad O rings in the long tube down the center of the oil filter. Check them out and replace them if they're cracked or hard. Typical of the 603.

markg612 · #8 01-13-2008, 01:30 PM

All better, cylinder 2 and 3 both lifters totally shot from tired oil pump, 0W40, unknowing daughter driver not realizing lifter noise was abnormal, killed 4 lifters. Replaced, oil pump first, helped but didn't solve the pulsing pressure, changed the 4 lifters, OIL, 5W40 Syn Valvoline and yes the orings on the oil filter through tub.

Works perfect again.

latitude500 · #9 01-13-2008, 02:29 PM

How would you know if the lifters is out? Did you have it checked out by a mechanic, does the engine sound louder? Just asking, because I don't know.

markg612 · #10 01-13-2008, 03:30 PM

Quote:

Originally Posted by latitude500

How would you know if the lifters is out? Did you have it checked out by a mechanic, does the engine sound louder? Just asking, because I don't know.

Hydraulic lifters, or for the purest, cam followers in this case tick when the engine first starts after sitting because they bleed off, and then again if they're really bad as oil temp rises to normal, my case. They were quiet until warmed. I be the mechanic. I fully warmed the engine so the lifters were good and noisy. The MB 603 manual calls for >.04MM clearance between the cam and the follower/lifter. One rotates the crank incrementally until each set of followers can be measured. 4 exceed the .04MM max. I pulled the cam, the good followers are virtually incompressible, the 4 bad ones were soft and springy to the touch. Once removed, they easily voided all their oil when compressed by hand with very little effort. The whole job was under an hour in and out. This 603 valve train is mindlessly simple to access. I've never seen oil pressure effected by soggy lifters, but one learns something new everyday.