Valve lash Adjusters HELP!!!!!!!!

Interesting... Maybe @Mendel Leisk or @ChapmanF might know?

 

They're something else going on . I don't see a reference to pre charging the lifters . You can pump them up on bench in bowl of oil . To see they do. Wen engine starts they pump up instantly more or less . Maybe oil pump issue . Timing cover based I believe . Have any pressure wen running ?? If they're an oil light there's a switch screw in manual gauge temporary start look at gauge maybe be shocked .

 

Perhaps those are bad also? If that's your issue.
The oil pressure pumps them up. If they bleed down overnight, they likely are not any good.
Did you use a screw drive or tethescope to listen at the valve cover to try to find what area the
tapping was coming from?
Are you certain the rocker arms are moving completely and freely?
Or perhaps a valve is bent?

 

mmmm I think maybe you forgot one of the little caps? Or maybe didn't tighten something down?
And if it is moving, then it is possible it is a lifter.
If you pinpoint it, or get close, maybe use some of the other ones you have free to replace that section?

 

They are moving, and if something is not correct, if they are sticking, they could be getting slapped with the
pushrod.

P.S. I just realized I said push rods.... That was dumb! There are no push rods.
And we were talking about the rocker arms....

Sorry about that. Check that they are sitting correctly. You might see wear...

 

2ZR has kind of a nice auto-lash setup. Overhead cams, no pushrods, in fact the cams are even over the rockers, pushing down on them. Each rocker rests on the lash adjuster at one end and the valve stem at the other. Result: the lash adjusters just sit still; their mass doesn't contribute to the moving mass of the rockers, the way they did in other engines I've seen where they lived in a moving end of the rocker.

 

This is a common description for all Prius engines and mechanical repair work based on strange noises in old cars can turn into an elusive nightmare as you're experiencing. My suggestion is to get some perspective and make an effort to seek out and listen to 5 or 10 other Prius like yours and see if they sound worse or better. Perhaps that could give some piece of mind?

 

You're talking about buckets with shims under them some are buckets with built in shim others are a literal shim under the bucket . So bucket gets reused. Clearance is measured old shim measured and a new shim ois calculated and put under the bucket. I'm getting ready to throw the 2z atkinson head buckets lifters all of it out .

 

See post 10, I updated it.

 

It will screw in right where you unscrew your pressure switch

 

This is a gen 3 thread, involving the 2ZR engine.

The 1NZ engine used in gen 1 and gen 2 has fixed, select-fit lifter buckets. (No shims for 1NZ; there are just 35 different sizes of bucket for the intake, and 35 more for the exhaust.)

But that's all about a different engine. A gen 3 has the 2ZR engine, with automatic hydraulic lash adjusters. Nothing to measure, nothing to adjust—as long as the HLAs are doing their jobs....