6.4 Lifter Failure

umbrae · Feb 5, 2013

What causes lifter failure on these motors? I have a 6.4 right now that I received already partially disassembled, and after removing a cylinder head I found 3 broken lifters (all intake side if I recall), a slightly bent push rod, broken lifter tray, and some evidence of a previously broken rocker arm on cyl 1 or 3. The head gasket shows no sign of failure, but cylinder number 3 was right full of oil. Not sure how it got there, there's appears to be no piston damage, and cylinder walls look pretty good. I hate diving into a job that someone else has already started, so im just looking for a little help on this one...

Dzchey21 · Feb 5, 2013

Usually poor maintained engines.

Pull the rods and check the bearings

If the pistons are ok check valves too make sure none are bent

umbrae · Feb 6, 2013

The drivers side had the rocker arm damage, and there was a lifter ready to come apart. Im going to replace lifters, pushrods, rockers and put it back together. Im going to agree with you on the lack of maintenance.

DEEZUZ · Feb 6, 2013

oil dilution... too much fuel from regen.... dip a spot of oil onto a piece of paper, if there is a clear ring outside of the spot, its fuel...

DEEZUZ · Feb 6, 2013

I would also replace the valve bridges too

umbrae · Feb 6, 2013

CTC DEEZUL said:
I would also replace the valve bridges too

I ordered all new bridges as well, and it did have quite a bit of fuel in the oil. Looking forward to seeing how it runs again on Friday.

DEEZUZ · Feb 6, 2013

just be as CLEAN as you possibly can with the fuel system... it is VERY VERY anal... one spec of dust or drop of water will fubar the entire system...

and take alot of time to bleed out the system before you go cranking away

Royboy1 · Feb 14, 2013

Broken lifters and bent pushrods will suck oil up on top of the piston, how often do we do valve sets on these trucks?

Big Angry Hillbilly · Feb 14, 2013

You mean valve lash adjustment?

Never.

3brorce · Feb 14, 2013

There is no adjustment on hydraulic lifters

Johnny77Mutt · Feb 14, 2013

Last time my motor was apart 3 lifters were cracked along with a bent pushrod. I bought mine with 28k and maintained it very well up to 100k when it was taken part. I should also mention that I never really beat on my truck either. Subed for more info.

Royboy1 · Feb 15, 2013

10-4 thanks, pretty new to this little stuff, always work on big Cat equip, that's really handy if they can make it reliable!

DEEZUZ · Feb 15, 2013

Food for thought.... Last I heard, the 7.3, 6.0, and 6.4 all use the same lifter... I have never heard of a 7.3 losing a lifter.

range91 · Feb 16, 2013

I would relate it to overload..springs are both 74lbs on 6.0 and 7.3 but obviously one more on a 6.0 per lifter

range91 · Feb 16, 2013

Another possibility that I had read before was a guy who had done a few bad lifter jobs and those trucks all had aftermarket oil filters.. Not to say solid evidence but low oil pressure at idle if the drain back valve isn't closed its going to take the path of least resistance