Check your 2rz valve clearance. - Page 3

NVTACO · 02-12-2012, 12:25 PM

how does a valve get tight? Cam bearing wear? Carbon build up?

bwill808 · 02-12-2012, 12:31 PM

Quote:

Originally Posted by NVTACO

how does a valve get tight? Cam bearing wear? Carbon build up?

F.M. '''F#$KING Magic'''' kinda like how a ECM works , you just it happens

NVTACO · 02-12-2012, 12:35 PM

haha like posi trac

cubical · 05-22-2012, 09:06 PM

bwill808,

Do you still have shims available?
All of my exhaust valves are tight so i ended up removing the cam shafts instead of fishing the shims out.The toughest was was breaking loosen the timing chain gear bolt.
Time to invest in air tools.

cubical · 05-22-2012, 09:14 PM

Quote:

Originally Posted by H2Oandy

I am not sure. The valve adjustment is fairly straightforward but requires a special tool and the shims. I would call you local mechanic I am sure they can give you a pretty good estimate over the phone. You definitely need to have it done.

You might want to check your compression levels. That will tell you if you already have any problems with the valves.

Got a quote from Toyota dealer $650.00,just curious i would not let them touch my vehicle.

HiluxRSA · 05-23-2012, 11:53 PM

Quote:

Originally Posted by NVTACO

how does a valve get tight? Cam bearing wear? Carbon build up?

Usually happens when either the valve face or valve seat (or both) wears away a bit. This causes the valve to sink deeper into the seat, effectively closing the gap (lash) between the valvestem and shim.......... when this happens, the valve does not get sufficient time to cool down on the valve seat, while cycling open and closed. It actually hangs open slightly, and thus starts to burn the valve face due to excessive heat.... almost like a cutting torch on the edge of a metal disc.......
Tight valve/s will usually show as a slight misfire, accompanied by a low manifold vacuum reading at idle........ (not sealing the cyl as it should)
Loose valve/s will emit a ticking sound.

howardc64 · 10-22-2012, 09:49 AM

Quote:

Originally Posted by HiluxRSA

Usually happens when either the valve face or valve seat (or both) wears away a bit. This causes the valve to sink deeper into the seat, effectively closing the gap (lash) between the valvestem and shim.......... when this happens, the valve does not get sufficient time to cool down on the valve seat, while cycling open and closed. It actually hangs open slightly, and thus starts to burn the valve face due to excessive heat.... almost like a cutting torch on the edge of a metal disc.......
Tight valve/s will usually show as a slight misfire, accompanied by a low manifold vacuum reading at idle........ (not sealing the cyl as it should)
Loose valve/s will emit a ticking sound.

Have a question going over the geometry of the shim-bucket design in my head. How increasing the clearance with a thinner shim can enable the valve to to cool better. Wouldn't increased clearance cause the valve to sit on its seat longer?

Like to know this before starting my valve adjustment effort on an 03 3RZ with 125k miles. Exhaust valves are all within spec but near the minimum.

NVTACO · 10-31-2012, 06:21 PM

Quote:

Originally Posted by HiluxRSA

Usually happens when either the valve face or valve seat (or both) wears away a bit. This causes the valve to sink deeper into the seat, effectively closing the gap (lash) between the valvestem and shim.........

is it wear or does the valve start to bend like a umbrella or both?

tacomaman · 01-02-2013, 08:51 PM

My smog guy said a reason for my HC being at the max spec could be i need a valve adjustment. Does that sound right? Toyota wants $395 to do it. I called around and no one seems to do it.

nxrunner · 01-02-2013, 10:29 PM

Quote:

Originally Posted by HiluxRSA

Usually happens when either the valve face or valve seat (or both) wears away a bit. This causes the valve to sink deeper into the seat, effectively closing the gap (lash) between the valvestem and shim.......... when this happens, the valve does not get sufficient time to cool down on the valve seat, while cycling open and closed. It actually hangs open slightly, and thus starts to burn the valve face due to excessive heat.... almost like a cutting torch on the edge of a metal disc.......
Tight valve/s will usually show as a slight misfire, accompanied by a low manifold vacuum reading at idle........ (not sealing the cyl as it should)
Loose valve/s will emit a ticking sound.

This info is correct.

Just had my valves done at the local stealership. $450 later... only need 3 shims at 10 bucks a piece.