Cummings 8.3 24 valve. Push rods not coming all the way up.

So my crosshead keeps falling off. I have adjusted all the valves to specs., but #6 intake and exhaust cannot be adjusted properly. I run out of adjusting screw. Rods are not bent, and tappets move up and down when I move the rods by hand.

This all started when I drove the truck with a plugged injector on #6 cylinder for about 15 miles smoke everywhere(LOL).

When I opened the valve cover to replace the bad injector, I noticed the crosshead on the intake valve had fallen off. Exahust valve was good and lash clearance was good.

I started the engine without the intake crosshead on just to test the new injector. Shaking and smoke was gone 90%. I then put the intake crosshead back on and adjusted lash to 0.010 cold. All was 100%. Come next day I warm it up about 30 minutes and start driving about a mile and both intak and exhaust crossheads came off. Now I cannot adjust. The push rods are way lower than all the others.

I have the exaust adjusted to the max and it is holding, I temporarly removed the crosshead and pushrod for the intake to get her home. Somiking a bit and shaking.

What can I do that will not cost me an arm and a leg to keep running for a few months until I get some money together to tare this thing down and repair it right? I was thinking of putting longer adjusting screws in the mean time.(Good or Not?)  

I would expect a rounded cam or extremely worn tappets would be the cause. If they are worn down, they won't hold the pushrods up where they need to be, thus you cannot take all the slack out of the valvetrain with the adjusting screws. I wouldn't run it, if the valves aren't opening all the way it is starving that cylinder for air and creating lots of back pressure on the exhaust stroke which could create extremely high cylinder temps for that one cylinder and possibly melt a piston.  
Logan
1995 12 valve Cummins 6.0L, 5 speed, 4x4, 600hp Valair Clutch. Air Dog 150, no fuel plate, benched pump, SDX 5x.014 injectors, Hamilton 181/210 cam and HD pushrods, Stage 2 Port job, 5 angle valve job, 60lb valve springs, ARP studs, O-ringed head, .020" head gasket, coated pistons, balanced bottom end, Fluidampr, PDI exhaust manifold, homemade intake manifold, HE351cw w/ 50mm wastegate over S475. 505hp 1156 ft/lbs pre-build

Yeah, before you replied to my original post, I went ahead and replaced the two bad tappets and two rod. Rod are fine, just changed them anyways. Ran perfect for two days then it happened again. My rods dropped and same thing. I just eyeballed the shaft and felt it with my hands for smoothness. Just imagine how ticked off I am knowing that it was a waste of time and money.

Now I have to do it all over again and replace tappets, shaft, one rocker arm and two pushrods.

I was wondering why the valves where not opening all the way and blowing oil to the shaft at the tappet joint point.

Hope it is not a sticky valve too. This is killing me. My wife will not even talk to me because thats our bread and butter maker.  

I would put a dial indicator on top of a good pushrod and measure how much rise it has, then put the dial indicator on top of one of the bad ones and measure it and if it isn't getting as much lift as the other one you will need a new cam and associated hardware (cam bearings, tappets, etc).  
Logan
1995 12 valve Cummins 6.0L, 5 speed, 4x4, 600hp Valair Clutch. Air Dog 150, no fuel plate, benched pump, SDX 5x.014 injectors, Hamilton 181/210 cam and HD pushrods, Stage 2 Port job, 5 angle valve job, 60lb valve springs, ARP studs, O-ringed head, .020" head gasket, coated pistons, balanced bottom end, Fluidampr, PDI exhaust manifold, homemade intake manifold, HE351cw w/ 50mm wastegate over S475. 505hp 1156 ft/lbs pre-build

Oh My Freaking God. So I replaced the camshaft and tappets again, this time 1 rod. Guess what? It happened again. Now it's the #1 Intake affected. I figured the whole thing out now, I am not getting enough oil up to the rockers to drip down and lube the camshaft and tappets. They heat up under high RPM's and engine temp rises to about 190 with an outside temp of about 60 degrees. I changed the oil filter, but I guess there was still enough metalic dust in the engine to plug it up a little. I changed the filter again and the oil pressure was at 20 idle and about 50 when running. Now it dropped to about 15 idle. Any ideas as to what can be causing poor oil circulation to the rocker arms? Im getting ready to throw in the towel.  

Oil pump perhaps? I would do a full lube system flush, aka full teardown cleanout and rebuild. If it can cause lack of oil to the rockers, it can cause lack of oil to crankshaft bearings and pistons just as easy.  
Logan
1995 12 valve Cummins 6.0L, 5 speed, 4x4, 600hp Valair Clutch. Air Dog 150, no fuel plate, benched pump, SDX 5x.014 injectors, Hamilton 181/210 cam and HD pushrods, Stage 2 Port job, 5 angle valve job, 60lb valve springs, ARP studs, O-ringed head, .020" head gasket, coated pistons, balanced bottom end, Fluidampr, PDI exhaust manifold, homemade intake manifold, HE351cw w/ 50mm wastegate over S475. 505hp 1156 ft/lbs pre-build