Herm

Just purchased a 1993 LS 400, 84,000 miles. Notice slight tapping - sounds like valve tapping to me.

Is the tapping to be expected at 84,000 ? Is adjustment necessary or is it OK to just ignore it ??

Any shortcuts to the adjustment procedure in the manual ? How much is the shim kit ? How much are the cam holder tools and where are they available - any alternates ? Would like to correspond with someone who has done it.

This is my first Lexus but I have done extensive work on other cars - engine rebulding, front end work, electronics troubleshootig, etc.

Thanks much !

Herm

additional info: I've had someone tell me valve adjustment is almost never required. Does this sound right ? They also suggested that if it is valve clearance related, the slight tapping might be cured by adding something to get the deposits off the valves - any suggestions of a product for this ? Does it sound reasonable ? Perhaps it is not the valves at all - any thoughts ? Possibly slight exhatst leak, etc. ??

Thanks for your thoughts - Herm

hyperopt

Checking valve clearance at regular intervals is suggested by Lexus. Although valve clearance don't usually go out of specs for lower mileage engines, it does sometimes go out for higher mileage engines due to wear 'n tear. Get the clearance back to specs if it goes out. Meanwhile, you can add thicker viscosity oil to quite down the ticking.

gebo

Toluene fixed mine at 2 qts/ tank of gas. See your fuel injector post.

akmpres

Try Max Life Oil 10w-30, i had the same tapping noise when i was using the 5w mobil, the max life cleared up the noise.