6.0 Issue

Hey Guys,
I have a buddy with a 6.0 that has a pretty fresh rebuilt motor. It has new injectors but heads had problems after the rebuild. A valve hung up in each head; I think it was an issue when the heads were hot tanked at the machine shop and not disassembled and valve guides relubed. Since then, both head have had a valve job. When we started the truck up after it was rebuilt, it ran smooth on a stock tune. Motor has an egr delete by the way. Now, a week later, the truck is running and idling kinda rough. The truck seems to run and idle smoother with a bigger tune. At WOT, there is a 3-4 second bad lag (almost exaggerated stock lag, without the smooth power curve) and then the turbo lights fast and hard. Sometimes the truck will pop and sputter in the higher rpms. I have not had a chance to put a computer on it but I will this week. Any ideas?

No one?

Be patient. It's a summer weekend and a growing site.

jdgleason said:

Hey Guys,
It has new injectors but heads had problems after the rebuild. A valve hung up in each head; I think it was an issue when the heads were hot tanked at the machine shop and not disassembled and valve guides relubed. Since then, both head have had a valve job.

Click to expand...

Considering this......

jdgleason said:

At WOT, there is a 3-4 second bad lag (almost exaggerated stock lag, without the smooth power curve) and then the turbo lights fast and hard. Sometimes the truck will pop and sputter in the higher rpms. I have not had a chance to put a computer on it but I will this week. Any ideas?

Click to expand...

and this, it sounds quite likely there's something else going on in the valve train.

If a couple valves "hung", you might have a rocker arm or pushrod issue now.

Wait.... The heads were tanked with the guides in?? Does it still have the same guides or were they changed with the valve job?

wetnsloppy4x said:

Considering this......


and this, it sounds quite likely there's something else going on in the valve train.

If a couple valves "hung", you might have a rocker arm or pushrod issue now.

Wait.... The heads were tanked with the guides in?? Does it still have the same guides or were they changed with the valve job?

Click to expand...

I believe they were. They never gave me a straight answer. As far as the guides being replaced, I have no idea.

WTF???

What kind of machine shop tanks the heads with the valves in?

Tank solutions and guide material may have changed over the years, but IMO, those heads should have never hit the tank if the guides werent going to be replaced. That's JMO though. It's the way I was taught 20 or so years ago by Don Moffit and Pat Bratton. (Ever seen "The World's Fastest Indian"? Don Moffit is depicted in that movie.)

The stock guide material is probably technically OK in most tank solutions. Just not something I'd like to see personally.

Regardless, my money is on a pushrod/rocker issue here. That's not to say a bunch of guides aren't fubared now.:doh:

Good point! Thanks brother ill check that out.