Rebuilt, retorque?

[fordfan]

I'm pretty new at the posting, but I sure get a lot of info from this site. Info I trust!
I am hoping someone can answer this. I have a rebuilt 2.9 V6 and I'm wondering:
1) how long, what are the stages for break-in?
2) when is it safe to do a road trip (mountains, but no load)
3) when and if re-torquing the head bolts is a good idea?
4) when should the Valve clearances be re-checked/adjusted?
Thanks for any input!

 

[brinker88]

Stages for breaking I cant answer,however ....the following I can:

If they engines running fine, why would you have to recheck and adjust valve clearances?

NEVER retorque head bolts and NEVER reuse them. When installed correctly, they stretch, making them bad to reuse.

 

[fordfan]

Thanks, I thought these were torque to yield headbolts, so that is what I was thinking also- nice to have my idea confirmed. I thought I'd come across something....somewhere... maybe it was all the diesel pages I was coming across while researching the zinc thing for the oil.
As for the valves, the exhaust is new too, so the whole thing sounds different- I think it's running as expected BUT... couldn't the clearances open as the new valves seat themselves?

 

[Sasquatch_Ryda]

The 2.9L has hydraulic lash adjusters (lifters), no need for adjustments there either.

If you are worried about cam wear on break-in then go get 5L of Shell Rotella 15w40 and do the first break in with that oil in it, it has a higher Zinc content and helps flat tappet cams wear in properly.

You can also go to your local GM dealership and ask for a bottle of AC Delco EOS (engine oil supplement) it is meant for breaking in engines. Dump in the bottle and the engine oil of your choice.

 

[RustedRanger]

EOS is real good for the initial break in...when first started...then change the oil before driving it. Also a tip for a new motor is to not hold it at the same RPM for a long time while driving.