Valve adjustment?

I came across something about the valve clearances on older engines needing to be adjusted periodically.

My recently acquired 2.7L 4 cylinder has just 80,000 miles, and I have no idea if the valves have ever been adjusted. I can hear a faint but distinct tapping noise from the engine while inside the cab when I'm moving really slowly in neutral or stopped. If I listen to the engine with the hood up, it gets drowned out. It's time to do a valve adjustment right?

It runs smoothly and I'm getting 21 MPG though. I guess I'll get it done and report back to see the sound goes away or I get better mileage.

 

tapping is better than no tapping in regards to out of adjustment valves. Damage occurs more often with too tight a valve than loose.

 

You could just check the clearance yourself on a week and decide if its worthwhile.

It's a time consuming job with little gains typically unless there's a problem.

I have access to the shims and tools at my work and I wouldn't be bothered unless I had a loud consistent tick or a running issue.

 

That's good to know. I can only assume both conditions hinder performance and accelerate wear and tear.

 

If that's the case I'll just hold off until either the tapping gets louder or the performance degrades.

 

You could do a compression check. Not entirely helpful but might catch a tight one and is non -invasive.

 

I adjusted my valves at 175k miles and they were just barely out of spec. https://www.tacomaworld.com/threads/tiffany-the-taco.374490/page-6#post-15408330
80k you shouldn't have to do anything, but it never hurts to check.

 

Your 2.7 Liter 3RZ motor is known to burn up mainly exhaust valves when the valve lash gets too tight. If I had one of these motors, I would absolutely check the valve lash periodically. Pulling the valve cover on this motor is beyond easy. Checking the clearances is EASY. Changing out a shim because you find one of your clearances out of spec is when the job gets more difficult but it can be done with a little patience and maybe some swearing too.

So OP, definitely pull the valve cover off and check your clearances for your own peace of mind and to avoid a very expensive head replacement or head rebuild. Waiting until you suffer a performance degradation is too late.

https://www.youtube.com/embed/f0zzsBhs3iA

 

You might live to regret this decision.

 

Ive checked mine twice in the last 5 years and both times had some that were out of spec. 260k on the clock though. Its not really a difficult job, though getting the cylinder 4 intake shim out is a PITA. Buy the tool if you need to replace any on the intake side. The exhaust side is easy enough to just pull the shaft off and reinstall if you dont have the tool. Dont forget to put a bolt through the scissor gear though.

 

I just watched Timmy the Toolman’s valve adjustment video tonight ( and yesterday, and last week).

Great stuff!

I just pulled the cover and checked my valves tonight. I have 149,000 miles, not sure if they were ever checked before ( I just got the truck). All my valves were within specs. Exhaust had one at 0.011, one at 0.012 and all others 0.013 or 0.014.

Intake all 0.008 or 0.009...

I s as Leo took the time to change plugs and run a compression test, just as a baseline for me.

wonder if the ticking you hear is the dreaded cracked exhaust manifold?

 

Me too. It’s no picnic to even check them. Moving shims around is an absolute joy.