tony, sumtimes i go stopid, hence why i tried 200ml of the mono40 oil + 15w-40 shell, lol. then the damn tappet noise re-surfaced, and i poured a can of bardahl-1 in my desperate attempt to suppress the noise, tapi tahan 2hari jer.. but, i cant put aside the fact dat d car has been efficient on fuel for the last few days, i whacked like always jer pun..
iam wit u about the lifters, as always tony. since the noise resurfaced after the overheat, then dat may be the cause of the lifters' noise
bro, i dont understand. previously once u've done the washer thing, was the lifters ok? lifters just need oil to operate, it doesn't matter what grade/viscosity of oil is it, as long as it has sufficient oil to operate normally, there will be no tik tik tik.
actually i'm surprised that after doing ur washer thing and no overheating incident ur lifter noise came back.....mind further elaborating further what happened after u've added washers into the relief spring valve and lifter noise returning? we can share share experience and join forces on thinking hat to solve the problem
---------- Post added at 07:08 PM ---------- 6 hour anti-bump limit - Previous post was at 06:20 PM ----------
Just a guide for Kenny,
Oil Pressure readings for the 4G93 without oil cooler
Idle (Hot) - 1 -1.5bar
Normal driving - 3.5 - 4.5bar
Boosting - 5 - 6bar
The above is just a guide. Will be lower if you have an oil cooler or using thinner oil. Mitsu always have low oil pressure on idle and this is well documented worldwide. I have had if for years without much issue. Most important is when you're flooring it. Pressure should be consistent. But I think you only hear the lifters when its on idle?? If it makes noise till 7k rpm. Then I suggest more shims!! Hahahahah... jk jk
Quite hard to get a new oil pump outside unless you willing to pay around 700-800 for a new unit from proton. No uprated ones, sorry. I have friends that swap in a new oil pump but after a while still tick tick tick... BUT doubt its your oil pump since its a NA pump and pressure should be better. Just get your mech to check with a good old pressure guage at the OEM pressure sensor location.
And just incase you're installing the new lifters here's something from Jeff Lucius my all time favourite mistsubishi guru
http://www.stealth316.com/misc/installing_new_lifters.doc
Good Luck
excellent link ! i see now that mitsu engines have a rocker arm + spring mechanism to transfer camlobe movement to lifter !!
its a bit different to mazda engines http://www.enginebuildermag.com/Article/60818/hydraulic_lash_adjuster_noise_on_199093_mazda_16l_dohc.aspx
for mazda, camlobes have direct contact on HLA to depress it.
for instances whereby a new oil pump is installed and lifter noise is still evident, can i speculate that the reason for this would be increased part tolerances through regular wear and tear on engine parts (specifically where the rocker arm/spring/camlobe/lifter valvetrain mechanism for mitsu engines), hence even after replacing to new oil pump, the OEM relief valve spring rate is still insufficient to maintain enuf oil up in engine head for lifter to use (only theory and speculating)
the theory is this: as engine parts become smaller through wear and tear, the clearances between components increases leading to increased oil
flow rate around the valvetrain assembly, hence resulting in low oil volume and little oil being retained in engine head for lifter to use. thus OEM spec oil pump is still not sufficient.
i must admit that this theory maybe wild, as it is unimaginable a new oil pump's relief valve spring rate is still now good enuf for lifters.
however, considering the wear and tear theory above, then a new OEM spec oil pump will do nothing to eliminate lifter noise (as per ur buddy's experience as well). the correct procedure would be to firstly check for psi reading on the old pump to determine if oil pump pressure is within spec, followed by increasing the relief valve spring rate on the old oil pump (to make the spring harder to depress) hence
slowing oil flow rate which would result in increased oil volume in engine head. then lifter is able to use the engine oil for its intended purpose(s). this should solve the problem unless like bro speed's case, his engine actually seized and overheated recently, which would bring a whole new dimension to the tik tik problem, which is something might have been broken.
i don't buy OEM manufacturer's theory that lifter noise problem will be solved with a larger inlet hole. the manufacture has correctly identified a starvation of oil problem on the lifter, and yet did not correctly identify the root of the cause of the oil starvation - which is soft spring rate on on oil pump relief valve. of course with a larger inlet hole in the lifter, more oil will be channeled in and eliminate the tik tik noise, but it will only do so assuming that oil flow will forever be maintained as a constant basis for the life of the car, and we know that this will definitely not be the case becoz oil flow is controlled by the relief valve spring and this spring will get softer and softer over time. granted, the new 're-worked' lifters would probably last a good 5 years or more, but the problem will come back ! to me, its a matter of cost-benefit approach, its so much cheaper to 'harden' the spring rate than to replace all 16 lifters in the engine. BUT with this DIY approach, suppliers don't make much money and THAT is the root cause of it all
