engine knock

[blackcloud]

I just got my 1994 4.0l ohv 2wd 5spd yesterday. I have plans for building it into a prerunner and would like to keep the 4.0.
I just got it running this morning on 6 cylinders cause the coil pack didnt have spark on cyl 2. From a cold start it runs fine and sounds good after about 1 min of running a faint knocking starts. When revved the knocking sounds a lot louder between 2000-3000rpm and goes away at idle. it will also go away with stedy acceleration on the highway but that is under load. if there is no load on the engine (in neutral) it will knock with any kind of increase in engine speed. It sounds like it could be a lifter cause a rod would sound worse when cold right?
Any help would be great i have read many posts about similar sounds but none with the same symptoms as mine any help would be greatly appreciated.

 

[RangerFabWorks]

rod or bearing knocks get worse as the engine warms up. because the oil gets thinner.

 

[BlackBII]

I would guess rod knock, simply because when most people describe the sound of a lifter, they use the word 'tick'. A knock is usually a lot louder...

I would get on youtube and listen to some rod knocks vs lifter tick, then decide which yours sounds like. Or just ask someone that would know...

 

[blackcloud]

if it was a rod it should make noise right off from the start up especially after sitting for 2 days. i went out and started it this morning and drove it and after 2-3mins when revd from idle in neutral would it make the knocking noise. im starting to lean toward the wrist pins. first things first though i need to change the oil cause it is about half a quart over full and god only knows how long the previous driver was driving it on 5 cylinders the oil has a lot of combustion and fuel smell to it and im sure it has lost viscosity and lubricating properties especially when warm.
Thank you for your in put and keep it coming knowledge is the key