fresh, slightly modified 4.0l ticking like diesel

so i'm new to this forum but for sure not new to the jeep world, but here is my problem that i need an answer to: i recently rebuilt the 4.0l in my 99 cherokee sport and Upon start up and for the first few minutes the engine runs like a sleeping kitten, but as the engine warms up to operating temp it develops a diesel like ticking sound, that is constant, and not spuratic, just a constant diesel tick as the engine idles and even as i bring the revs up and in a way sounds like a small exhaust leak which i'm sure it not, but to help you guys out here are the exact specs of my engine and parts on it:

-4.0l block bored .030 over
-stock crank, and rods
-hyperutectic pistons
-comp cams 68-232-4 cam
-mopar performance spring (to deal with the extra lift) these springs are also higher rate
-3 angle valve job
-comp lifters that cam in the cam kit
-comp cams timing set
-knock off banks header
-gasket matched intake/exhaust
-stock oil pump
-all the rest or the drivetrain (rocker arms, push rods, valves) are original to the engine
- for the first two oil changes i'm using comp cams break in addative

now my question/problem is whether this ticking is characteristic of one of the parts i have say the cam or header or maybe due to the stiffer springs? for example and maybe i should just move along an live with it, or if anyone could shed some light, would like to figure this out before i drive too much farther with this engine (only has about 100km on it right now, yes km...i'm from canada haha)

thank you all,
kyle

Check your exhaust bolts..

Johnnie Walker said:

Check your exhaust bolts..

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yep yep...

also these engine do tick a lot

Did you break in the cam? If not, it's quite possible that you flattened a lobe.

Pull off the valve cover and check to see that all the rockers are moving fully.

yes i broke in the cam above 2000rpm for 20 minutes in total (had to shut it off at ten minutes the first time to top the fan that was rubbing on the shroud, the started it up again and continued on for another 15minutes to be safe)

and if i flatened a lobe would it not tick un uniformly and all the time, not just when warm?

spark plugs tight
exhaust leak
adjust lifters

in what way do you mean adjust lifters bj-666? i just torqued down the rocker arms to the recommended spec when i assembled it

so i'm getting this thread going again but now i know i need push rods and the length i need which is .030" longer than 9.650". phoned comp, they got nothing, and body know any other companies suitable for my needs?

Hesco has some 9.70" pushrods.
http://www.hesco.us/

Are you certain you need longer pushrods? Is it because of the cam?

Summit racing or jegs will also sell different lengths of pushrods.

The ticking sound is a characteristic of the 4.0 engine. It is due to the valve train design. For some reason some engines are louder than others but they almost all make that sound. If it is not loud enough to hear while driving I would not worry about it unless it changes or gets significantly louder.

RCP thanks i will check those out,
PORCH i'm almost positive its the pushrods, all the rocker arm wiggle a little due to barely any preload on them,
jeeperjohn, its not the usual 4.0l tick haha trust me, we've had 7 of these jeeps, its making more noise than any we've had ever had, and very noticable while driving once its hot

as far as we can tell the ticking is due to the lifter not being able pump up enough when hot due to enough pre load not being there, to fix this, getting longer push rods will up the preload (currently at about 0.010") to the recommended 0.035" -0.040"

You should use an adjustable pushrod do determine proper length,the rocker contact patch will show you the proper length.

http://www.youtube.com/watch?v=153_r38bn9M

Does it sound like that?

RCP Phx said:

he rocker contact patch will show you the proper length.

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Not on the 4.0L. Being that it is a non adjustable valve train the push rod length won't effect rocker contact with the valve stem. It will only change the preload. Unless of course the pushrod is very long and holds the valve open. If the rockers were adjustable with the rocker bolt(or nut in most cases) then the push rod length would effect the valve to stem pattern. No bolt on roller rocker works like that on the XJ.

Smith Brother's is also a good place to get custom pushrods, and inexpensive. http://www.pushrods.net/ Probably looking at $80 a set.

actually talyn it does kinda sound like you video but mine is definately more noticable near the valve cover, and i'll check those guys out for sure, we're gonna do one last measurement (to see if any how much preload we DO have) and then we'll order then