new lifters bleeding off

[tonyjklh]

i have a fully rebuilt 4.0 engine. runs good but the lifters bleed off easy. when i start the truck they almost always start clicking for about 5 seconds or so. and after the engine fully warms up the bleed off at idle. i can hear them start ticking for a few seconds and then shut up and then do it again. as soon as i hold it about 200-300 rpm above idle they shut up. i let it back to idle and they are quite for about 15 seconds then bleed off again.
theres about 4000 miles on the engine.
any help would be great!
oh and they are new melling lifters

 

[boominXplorer]

Have you put a mechanical gauge on the truck to check the oil pressure?

 

[1badfox]

^^ that's what I would suggest.

 

[tonyjklh]

i have a mechanical gauge already. the pressure seems low to me at idle while others say that its fine. 40 at 2300 rpm, 8-15(most of the time at 10). i havnt been able to fix the oil pressure. new pump, crank clearances checked, etc.

 

[Joe Dirt]

Are you certain that the clearance was set correctly when the new lifters were installed?

 

[tonyjklh]

Are you certain that the clearance was set correctly when the new lifters were installed?

when you say clearances set correctly what do you meen? if your refering to pushrod length, its a completely stock engine, no performance upgrades at all. so i used stock length pushrods as well. as far as i know there is nothing adjustable with the valve train on the engine

 

[Joe Dirt]

More on the rocker arm end- you're still running hydraulic lifters I assume, so you shouldn't have an issue there. Make sure the rockers are tight. If you're still running a 2.9L, those are notorious for a poor oil flow design and ticking noises. Most guys just play with different/more oil unless you want to mess with free floating rockers, chamfering shaft holes and messing with rocker pedestals.

 

[tonyjklh]

More on the rocker arm end- you're still running hydraulic lifters I assume, so you shouldn't have an issue there. Make sure the rockers are tight. If you're still running a 2.9L, those are notorious for a poor oil flow design and ticking noises. Most guys just play with different/more oil unless you want to mess with free floating rockers, chamfering shaft holes and messing with rocker pedestals.

its a 4.0. has new hydraulic roller lifters, new rocker arms torqued acording to the manual

 

[1badfox]

Are you sure the lifter bore diameter was within propper spec? Worn lifter bores may need to be sleeved otherwise the oil isn't making it up to the rockers and won't keep the lifters pumped up. Or even checking the lifter diameter? Due to manufacturing tolerances they can be as much as .005" out from what I've seen. I wouldn't be worried about 10 psi at warm idle on a high mileage engine, but it's low considering it's been rebuilt. what exactly were the main bearing clearances?

 

[tonyjklh]

Are you sure the lifter bore diameter was within propper spec? Worn lifter bores may need to be sleeved otherwise the oil isn't making it up to the rockers and won't keep the lifters pumped up. Or even checking the lifter diameter? Due to manufacturing tolerances they can be as much as .005" out from what I've seen. I wouldn't be worried about 10 psi at warm idle on a high mileage engine, but it's low considering it's been rebuilt. what exactly were the main bearing clearances?

i didnt check the lofter bores, the engine was a fairly low mileage engine when i got it from the wrecking yard so i dont think it could have wore out that much(75,000 and it was not an odometer that starts over every 100k).
i dont exactally remember the clearances as its been a while. i know that #'s 1,2,4 were right at the high end of the "desired" limits, and #3 was more towards the high end of the "acceptable" limits.

 

[Sedition]

What is the grade of oil you are using?

 

[tonyjklh]

What is the grade of oil you are using?

5w30 full synthetic.

 

[Sedition]

Good choice

 

[Sedition]

What I would do

This is what I would do. Add a stop smoke oil treatment to thicken up the oil a little then retest oil pressure at idle. Take her for a drive, say 5 miles or so then retest oil pressure and see if the lifters have dulled.

 

[tonyjklh]

This is what I would do. Add a stop smoke oil treatment to thicken up the oil a little then retest oil pressure at idle. Take her for a drive, say 5 miles or so then retest oil pressure and see if the lifters have dulled.

the problem with doing that is thickening up the oil is not a fix, more just a quick temporary patch. it dont change the fact that there is a problem.

 

[Joe Dirt]

But it is also an inherently poor oil flow design... Without knowing exactly how much tapping is going on, it could be what drivers of 2.9L engines would consider annoyingly normal...

It can really be anything- poor design, worn cam, worn cam bearings, blocked pushrod oil passages, even a weak oil pump even though it's new... You're going to have to take it apart and make sure everything is flowing freely if it's bugging you. Is it one lifter or multiple?

 

[Rick]

Did you bleed the new lifters before installing them?

 

[tonyjklh]

But it is also an inherently poor oil flow design... Without knowing exactly how much tapping is going on, it could be what drivers of 2.9L engines would consider annoyingly normal...

It can really be anything- poor design, worn cam, worn cam bearings, blocked pushrod oil passages, even a weak oil pump even though it's new... You're going to have to take it apart and make sure everything is flowing freely if it's bugging you. Is it one lifter or multiple?

its not the cam or bearings its all new. Just as well the block was cleaned thoroughly. And all the rockers, etc are also new so there are no blockages. I have already taken the engine out and put a second new oil pump in thinking that was the problem, but it made no change. Its about 2-4 lifters having trouble. its intermittent how many have problems.

 

[Rick]

Did you bleed the lifters before installing them?? Hydraulic lifters have to be bled.