When to do valve adjustment?

X2 what he said. If left out of spec the ensuing damage will cost a whole lot more than a couple of hrs and the price of shims.

Don't ask me how I know.

 

so whats better loose .014 , or tighter , smart guy i dont know, read a forum stating .015 for v6 is ideal , but , the spec is .011 .014 i have asked wrote like 100 forums with no straight answer ffrom any one, i dont want to be the guuiny pig but i will if i have to , . the new v6 1gr tacoma etc. changed there spec to include .015 , i am debating . what do u think about burnt shims hot spots , same for my cams r they ruseable

 

I'll echo a lot of what Davidch said 5 years ago.

I just did this on my new to me 2003 2.4l with 110k miles. The service records did not indicate that the valves clearances were ever checked.


My #2 exhaust valves were both at 9 mils (spec is 10-14 mils) and both my #4 intake valves were at 6 mils (spec is 6-10 mils). So I replaced the shims on these 4 valves to get 11 mils on the exhaust and 9 mils on the intake valves. All the other valves were in the middle of the specified clearance range.


I thought I would pass on what I learned along the way:


The service manual for my truck says that the valves should be checked every 60k.


Most of the factory installed shims have a 0.01 mm (0.4 mil) thickness increment. Check the valve adjustment charts in the FSM.


The replacement shims are only sold in 0.05 mm (2.0 mil) thickness increments. So save those original shims in case you need to get in range with a thickness that is no longer available.


Dealers charge about $7 per shim with the on-line 30% discount. The bend over counter price can be double that if you are lucky. Most local to me dealers did not have the shims in stock, so plan ahead for truck down time.

These guys sell the shims for $5 each, but you have to buy 4 at a time:

http://www.cylinderheadsupply.com/valve-clearance-discs-28mm.html

They also sell a tool you can use to lap your existing shims down to size.


My machinist friends don't have a problem with lapping shims because the case hardening is much thicker than a couple of mils. But they say that lapping a mil of hardened steel will require a lot of elbow grease. If you go this way, they recommended placing the lapped side down so the un-lapped side interfaces with the cam lobe.


I did not remove the cams and would not do so even if I had to replace all 16 shims! I found a great tool on You Tube that makes it very easy to push the valve bucket down even for the cylinders near the fire wall:


Motion Pro 08-0018


I still used the wedge from the Schley Products 88250 valve adjusting tool kit, but the pliers were too big and didn’t press the bucket down far enough without a struggle. To each his own.


This is a precision operation so use good quality measuring instruments and make sure they are accurate.

My Starrett dial calipers were not good enough because they only have 0.5 mil resolution. My Mitutoyo micrometer has 0.05 mil accuracy and resolution so it is good enough. My feeler gauge set agrees perfectly with my Mitutoyo micrometer, but would not agree with my Starrett calipers.


So check your feeler gauges against your micrometer. I found the Toyota shims were dead nuts so your micrometer should agree with them too.


Really if you cannot get the micrometer, feeler gauges and shims all on the same page, please buy better tools before attempting this project.


EJPHI

 

Would be curious to know how many here have adjusted the valves on a 2nd Gen Tacoma V6 1GR-FE engine and at what mileage this took place?

 

Hi davidch, I hope you’re still active here and if anyone else who can answer my question with valve adjusting. So I have a 2000 Toyota Tacoma 2.4l 2rz-fe at 281k miles, I’m currently adjusting the valves because I have a cylinder 1 misfire (I have checked for vacuum leaks, replaced vacuum hoses, fuel filter etc.). I’ve measure the intake side for cylinder 1 and both valves are in spec; however, the exhaust side for cylinder 1 is too low. The back valve measurement for cylinder 1 is .004 inch while the front valve measurement is not available, even at .0015 inch that does not go through. So I know I’ll have to measure the shims (I have a micrometer) but should I also think about replacing the buckets? What else should I look into before replacing the shims now that I have the valve cover off?

Thank you for any helpful feedback. I greatly appreciate it.

 

If you have valve noise at 84k take it to Toyota for an evaluation. Also don't use octane fuel rating higher than what is required. The ECU, catalyst system will work overtime adjusting for th octane change it's expecting.

 

This is a Second Gen forum, as well... So maybe check the First Gen forums for answers on pre-2005 engines? I was under the impression that the 4.0 V-6 has self-adjusting valves or they need none?

 

That is incorrect. The 4.0 liter 1GR-FE engine does not have self adjusting valves lifters.

The 4 cylinder 2TR-FE does have hydraulic lash adjusters however.

2TR > 1GR!

 

You Sir have the Taco tick as we all do! It's probably not the valves you are hearing!

 

When its time for cylinder head gaskets.

 

Can you expand on this, please? I have had all the servings performed by Toyota on schedule while the truck was under warranty and have since (now a 10-year-old truck) had an independent, Toyota certified mechanic perform them. Not once did "valve adjustment" get mentioned... So, what are the facts?

 

Well the simple facts are just as I stated:

The 4.0 liter 1GR-FE engine does not have self adjusting valves lifters.

The 4 cylinder 2TR-FE does have hydraulic lash adjusters however.

I am not responsible for what your mechanic(s) have or have not told you. Granted the Toyota Engines rarely "need" to have the valves lash "adjusted". The 1GR not having hydraulic adjusters is one reason they are noisy.

 

Pretty sure all Toyotas since the late 1980s or early 1990s have hydraulic tappets and don't require adjustment.
When they eventually do need adjustment, you would rebuild the engine or just sell the vehicle.
EDIT: It's very hard to believe (and understand why) Toyota would design a modern engine without hydraulic adjustment. The 4.0 is not a racing engine and the specific output is not very high.

 

Y'all should look at dates, and how this thread was revived.

 

OMG an old thread, this is a serious problem.

 

See post #29

 

Jimmy already answered your question but FWIW (maybe not much, ha!) I recently checked mine at 198k when I installed new exhaust cam gears with 3 more degrees of retard which @mightytacoman sells. Valve clearance was still in the middle of the range.

 

I took my upper end apart to replace springs and install my upgraded camshafts last fall. This was at under 100k miles.

I checked the clearances on the stock buckets/camshafts and they were exactly at stock tolerance. Exactly. Meaning like, no wear at all. I imagine I could have gone until the heat death of the Universe without having to adjust them.