KC98LS

Maybe this is a dumb question, but does the 98-2000 LS400 require valve adjustments?

If so, what is the interval, and easiest way to check?


My engine seems to have a bit of a noticeable tick at lower RPMs, I know it's normal to a certain extent, but it seems to be getting louder over time.

billydpowe

iTrader: (1)

are you running premium fuel? or regular?

djamps

Could also be an exhaust manifold leak. I don't think you can adjust the valves easily. You basically have to take the cams out and change the tappets depending on the lash you're seeing... trial by error process, extremely time consuming and possibly expensive if you need a bunch of new tappets or mess anything up in the process..

KC98LS

Premium gas (91 octane) exclusively.

Okay, good to know. I don't believe it to be an exhaust manifold leak.

I take it the 3rd gen 1UZ DOES require valve adjustments then?

timmy0tool

iTrader: (7)

doesn't mention it's a 98+ or not but a help nonetheless.

https://www.clublexus.com/forums/ls-...hts-on-it.html

edit:
in his profile, it's a 1991 LS400. doh!

aptoslexus

Maintenance schedule for the 98. I assume by audible they mean if it's making noise, you might have a valve clearance problem.

dicer

Looks like they require it, and I'd worry about that "Front differential" ???

Yamae

LOL. Open your eyes, dicer.

dicer

I did item number 10 on the top chart.

I'm just wondering when the ls400 had 4 wheel drive.

djamps

Doesn't look like it's a 'required' maint. unless it's 'audible' (+). Inspect every 60k mi or 48 months (using your ears), adjust only IF it's making a racket.

qha_vn

adjust valve clearance doesnt seem to be a DIY job. from what I know it's a precise job for the pros.

believe it or not, I got a leak exhaust at the cats and the engine heard tick like crazy until I got the leak fixed. my valves still have tick but greatly reduce. i dont know why as they seem not related.

valves are adjusted by shims with a special pliers like this one use the pliers you will not need to remove the cam shaft

nthach

The 1998-on UZ family engines are shim under bucket lifters like some motorcycles, and supposedly shims from a Suzuki or Yamaha will work. You'll need to pull the cams, not a job for the faint-hearted.

Stroock639

the front differential lines only apply to the ES and LX, notice how the others don't have black x's in the boxes?

cbrkat28

+1 but I'd call it a total PITA instead of not for the faint hearted lol...but unless we're using different terms for the same things then Honda's are not "shim under bucket" My CBR started making a ticking noise so I did the job thinking thinking the valves just needed to be adjusted and eventually discovered that one of the valve springs had a weak inner or outer spring (can't remember) despite both being acceptable in terms of length. So if you've already gone so far as to remove the cams and have access to the valves, check the tension on the springs.

Moral of the story: Better to be paranoid and safe instead of careless and very sorry.