Valve lash inspection / adjustment on 4.0 V6?

Did some searching on 4.0 valve adjustment and inspection procedure. I see a lot of chatter (pardon the pun) on the subject, but could not find an example of someone who actually went through the process. Checking seems about as easy as doing valve cover gaskets. Adjusting seems a bit harder as it requires cam shaft removal and bucket replacement.

Has anyone actually checked their valve lash? If so what were the specs?

Has anyone actually adjusted their valve lash? If so than you should get some sort of enthusiast mechanic award!

 

Sub'd for info

 

Why do you feel the need to /check adjust valve lash?

 

Well there are about 500 plus threads on the taco tick and various ticking and noisy engine complaints. Its common for these engines to be noisy but it is NOT universal. Some of these engines don't have the taco tick, some do. But the common theme is that there is no known cause or solution.

Parallel that with the threads on valve adjustment. There are plenty of those (some are the same as the taco tick threads) too, and they usually end with the valve adjustment being unnecessary, complicated and or expensive. I was not able to find a single thread or post where someone actually checked the valves and reported their finding on a 4.0 V6. I am curious if anyone has looked into this.

I have no idea whether I need to check or adjust my valves, at this point I am just doing research.

 

if you think you need valves adjusted sub 250k miles you don't take your truck to redline enough.

 

I wouldnt bother with inspecting it unless there is really loud valvetrain noise or rough idling. Aint broke. Drive on!!

 

Shim under bucket valves, like the ones in the Tacoma, often get tighter with mileage and age. It is possible that Toyota knows this and purposely adjusts the valves looser to the high end of spec; knowing full well that few if any will ever attempt to check or adjust them. This is where the famous "tic" may be coming from.

 

^^^^^^^^^^^ This.

Or get a 4 banger that has hydraulic lash adjusters.

 

May be the reason why that fella in North Carolina got 1.2 millions miles on his Tacoma - his is a 2.7L

 

The best way to mask the Taco Tick is to take it to redline more often!

 

yes, valves out of adjustment get quiet (tight). the 4L is a metal engine with metal parts moving in it.. sometimes when metal touchs metal it makes noise. lol

 

I'd say the vast majority of "taco tick" inquires are from new Toyota owners who are not used to the injector noise. These engines really are noisy compared to other OHC 6 and 8 cylinders out there. And being an OHC engine, unless either the block or heads are decked, there simply is not a need to "adjust" valve lash.

 

OK here is the deal on shimmed valve adjustment the old 3L had issues it was valve stretch yes hammering into the valve seats stretched the valves over time so the clearance became less but techknowledge moved on now all of the modern parts ware pretty much equally so the clearance should remain the same over the life of the engine. If you want to have at it there are 24 of them so have fun be sure to have a large box of shims and a good digital micrometer!

 

He's replaced the engine in that time

 

Yeah...at around 800,000 miles. Added another 400,000 since that.

 

So the engine only ever had 800,000 on it not 1.2mil

 

Go watch the video

 

FYI there are no shims in the 4.0 v6 just buckets. Buckets come in a variety of heights, pick the one that facilitates the correct lash.

 

I have not done any

I think the shim is on top of the bucket

 

I did. He changed it due to it using coolant