Bad News Bears (thumping and ticking)

Well a month later after resetting my vavles and fixing the problem, i pulled my 5x.014's and had them pop tested ( all of them sticky, popping between 280 and 250bar) so i tossed in a set of the thin .020 washer under my stocker injectors and did a retorque and valve set.... 3 days later my #1 exhaust is wayy outta wack again, so this time i set my hot lash 2 .06 and .016 (i have a +.010 thick hg and rotated my engine by hand to make sure of clearance) trcuk ran fine for a few days.... then today i did a fairly long hill in 4th gear 2 about 1900rpm, coststant load @ about 10psi and 1900rpm... not really chugging it or over revving it, when i stopped it was thumping... sure enough #1 exhaust is slightly outta wack again. reset it to .016 again and seems to run fine.

Can anyone think of a reason why that nut would back itself off ? pushrod height does not change so i doubt it's a lobe or lifter, and spring height has not changed either. Seems like it works itself loose... this time when i set it, i torqued it to 25 ft/lbs and soaked the nut and adjuster in brake clean....

ideas ??

could it possibly be the early signs of popped hg ??? (sumhow////)

i have the pacbrake 60lbs springs in this head on the exhaust an intake sides.... perhaps this one has been pounded out and it's causing the problem ???
 
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I can bet that you are losing that lobe on the cam shaft. Did you measure lobe lift with a dial? I am willing to bet you are wiping that lobe off. Had that happen to me on an 24v I used to have.

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Could just be the nut does not want to stay tight, new rockers are not expensive you could try that.
 
Well, I have a few spare rocker assemblies and a few spare pushrods. No havnt hcecked with a dial.... although I do have a cam, lifters and pushrods out of a core sitting @ my buddies shop that I could swap in.... though I do have to be on the road by 2pm today on my way to calgary.... fug, I knew I shoulda just pulled the damn thing 3 days ago when I rretorqued my head. Oh well, guess I deal with it for a week an fix it next time I'm home. Hhope my rebuild kit comes from puredieselpower by then so I can throw it in my core motor with a 181/210 outta my friends 24v.

Def gonna look closer @ pushrod travel though.
 
unless your finding the nut loose im going to put my money on the cam lobe taking a deuce.
 
Had the same thing happen to my 12v. The shoulder of the lifter broke and slowly wiped the lobe.
 
Have you been running a ZDDP additive? I thought it was only necessary for break-in but its needed even on the pre-DPF oils. I ran delvac, rotella and some AMSoil synthetic over a period of 20k mi with regular changes and the cam self-destructed a couple lobes due to low zinc content.
I was a little skeptical at first but after doing some research I think this was the cause.
I found a roller cam + lifter setup for it, but looks like its a pretty aggressive cam. 180/220 is fine for what I do.
 
either my lifter is hooped, or the cam lobe is wiped... i have next to no adjustment left and im out in alberta..... got an 8hr drive home tommorow, then i pull the cam etc. and admire whats left before throwing in the new stuff.... yeah i shouldnt be driving it, but its tough an hasnt let me down yet.... worse comes to worse i got a core motor and a rebuild kit sitting in my shop waiting to be rebuilt and put in.
 
yep ill bet you wiped out the cam lobe.. im also willing to bet that the lifter lost its shoulder and started the problem.. i hope you make it home man.. sorry about the loss but im sure the next one will be better..
 
meh... not too worried, ive beaten on it pretty good for 100,000miles

im tempted to jus throw a new cam in and run it some more... fuggit
 
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