Valve Adjustment

[UberSilver]

Originally Posted by yarista

General Question:

Does anyone ever adjust Yaris valves? I hope not. They have shims. Motorcyce valves that use shims need regular checking and adjusting. Perhaps the hardened valve seats (i assume they have hardened seats) on the Yaris keep them in adjustment. I have an 07 and an 09 USA Yaris.

I do not have a factory repair manual, so I have no idea about what Toyota designed into the Yaris. But I've worked on 100's of motorcycles, that started using shims back in 1973.

If there shim over bucket? Valve adjust is easy. If there shim under bucket, still easy, but will take 3x the time, as you'll need to remove the cams.

I prefer a shim system, as they keep there adjustment for much longer then a tappet system(most of the time, but not always).

And when you stated ~Motorcyce valves that use shims need regular checking and adjusting.~ Thats not true, unless your speaking of poorly design engines, such as Ducati's. It's common for Honda's to go 100k without a valve adjust. My VFR has 60k. I've checked it at 30k & 50k and it's still within spec.

[jambo101]

I doubt you'll ever need to adjust the valves on the life of your Yaris...

[Absolutely Red 12]

Originally Posted by UberSilver

If there shim over bucket? Valve adjust is easy. If there shim under bucket, still easy, but will take 3x the time, as you'll need to remove the cams.

The cams need to be removed.

From the manual:
The adjustment of the valve clearance is accomplished by selecting and replacing the appropriate valve lifters. Adjusting valve lifters are available in 35 increments of 0.020 mm (0.0008 in.), from 5.060 mm (0.1992 in.), to 5.740 mm (0.2260 in.).