vg30 hydraulic lifters

[skywhine]

Kind of an odd question:

I am curious how offten vg30dett lifters fail. 40p heads, just standard hydrolic lifters. Mine personally have 120k.

The reason a ask, I work on cars for a living, and i recently worked on truck that has came back twice now with failed hydrolic lifeters after both heads were rebuilt by a machine shop. I installed the heads, everything torqued to spec with a very expensive snap on torque wrench. All done by the book Just your standard head job. Truck came back about 2 months after the head job, misfiring on cyl 3. with a loud rattle. Pull the valve cover off, cyl 3 exhaust valve rocker popped off because the hydrolic lifter had bound up. Replaced the lifter, runs great. Another 2 months go by, comes back, same complaint. Pull valve covers off, cyl 4 lifter siezed, popped the rocker off again. This preticular truck is a SOHC v6 domestic engine. 1997 iirc.

Im currently in the process of rebuilding my VG30DETT and would like to avoid this issue as its alot easier to replace the lifter on the truck than a z32. Im doing a complete overhaul as apposed to the head only job i did on the truck, wasn't my choice on the truck.

When re assembling the heads should i reuse the stock lifters and cams or use Tomei solid lifters to aviod failed hydrolic lifters? How much damage would a failed lifter on a VG cause?
On the truck no damage was caused, the exhaust valves just weren't opening.

[t.mcginley.jr]

Solid lifters are only for high performance, like 600+hp and even then you really don't need them.

Most hydraulic lifters bind up or deflate either because the oil is too thin and thus the oil pressure isn't high enough to keep them inflated. Another reason is that over time the lifters get an oil film buildup on them, causing them to eventually bind up. Usually in our cars this is solved by either running thicker oil, or by putting in some Marvel Mystery Oil for ~100-150 miles and then draining and refilling with fresh oil.

In the VG30DETT, there are no rocker arms, the cam lobes contact the lifters directly. So when the lifters bind up, they will start ticking and you will probably experience some power loss, but no major damage occurs.