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Adjusting Valves On 1zz-fe

By fishexpo101, February 21, 2005

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I went ahead and checked vlave clearances on my Corolla and took some pics for good measure (reference for hose locations, etc.)

Wanted to take a peeks and see if things were clean or dirty under there - any sludge, deposits, or varnish - and if the valves needed adjustment (somewhat noisy lately).

Photos:

http://photobucket.com/albums/v620/fishexp...djust%20Valves/

The pictures speak for themselves - there was some varnish and slight deposits - but nothing to be worried about. Looking at the valvetrain - everything was pretty clean with very little wear on the cam lobes and lifters. The engine has about 105K miles and is about 5K into the oil change (wanted to do it this late in the change - that way I will change oil soon to help remove any dirt or debris that may have fallen in).

Tips - makes sure to blow out the sparkplug holes before removing the plugs and around the outside of the valvecover to help reduce the possibility of dirt falling in. I used a OEM Toyota gasket - cost me $25 at the stealship. Could have used FelPro or others - but wouldn't have saved any more money - plus fitment could have been an issue. Can't go wrong with OEM gaskets.

I disconnected the wire loom, any brackets attached to the valvecover, removed coilpacks and plugs, and moved everything out of the way that could have prevented the valvecover from coming off.

Most of the bolts were 10mm on the valvecover, coilpack hold downs, and for the wire loom. Need a 19mm socket to put on the crank to turn the crank CW to get it to TDC on cylinder #1 (make sure to match up to 0 degree mark on crank pulley) - compression gauge will help, but you can also verify visually by looking down into the sparkplug holes or putting your finger over the #1 sparkplug hole. Once there - you can use tappet feeler gauges to measure clearances (between camshaft lobe and top of lifter) between the intake and exhaust valves on cylinder #1, intake on #3, and exhaust on #2 - then turn the crank over a full revolution to measure the others.

All said and done - the tolerances on the intake were supposed to be between 0.006-0.010 inches and the exhaust to be between 0.010 and 0.014 inches.

I found that all intake clearances were tighter than 0.007 and exhausts were all on 0.010 or less. Basically - nothing was wrong, valves were all on spec. - engine showed very little wear that was also verified with used oil analysis done yearly (UOA). Chaulk up another good engine to Toyota.

Motor oil used - Mobil 1 synthetic every 7500-8000 miles, OEM filters. Never "babied" the car - daily driver, but made sure all maintenance was on schedule. First 30K services done by dealer (free service promotion on schduled maintenance - I did every other oil change myself) - everything after that was done by myself.

Thanks for the info fishexpo!

Nice pics. Mobile 1 looks like its doing a good job keeping it clean with a 7.5-8k OCI!

G

Great walkthrough! I love that nice golden color in there. BTW< the ad at the top of the picture page startled me pretty good!

Thanks for sharing with us, Fishexpo. It's nice to see how well your engine is doing.

Ti-Jean

1) Did you attempt to clean your valve cover? If so, what did you use?

2) Does your engine use any oil? As some 1ZZFE seem to be plagued by high oil consumption caused by sticking rings. M1 might have prevented this though.

3) How did your UOA's look like? Did you post them anywhere?

4) Does your engine have the iridium plugs? Have you replaced them yet?

5) Mainly highway driving, long distance, cold winters and roadsalt where you live?

I too, prefer to do my own regular maintenance and you have just demonstrated that a car can just last as long and be in perfect condition even if you don't visit the dealer for scheduled maintenance on a regular basis.

Also, valve adjustments are much less required now than they once were. Unleaded gas and better oil seem to have helped a lot. Hondas used to require a valve inspection and adjustment every 48000 km (lock nut type). But now, we don't hear much about the necessity of this service. I vividly remember my first motorcycles in the late 70's...

Thanks for sharing your experience with us.

Guest goldeneye

Thanks fishexpo101. Your posts are always informative.

Good to see that your engine is doing fine. Since I'm also using Mobil1 Super Syn and Toyota OEM filter, I feel more confident now that I see the positive results on your car. I recently drove 1000 miles and checked the oil level after the drive and found absolutely no oil consumption. I was initially concerned that my LE05 may exhibit excessive oil consumption after it was unnecessarily flushed by the dealer, but thankfully I haven't seen such symptons.

1) Did you attempt to clean your valve cover? If so, what did you use?

2) Does your engine use any oil? As some 1ZZFE seem to be plagued by high oil consumption caused by sticking rings. M1 might have prevented this though.

3) How did your UOA's look like? Did you post them anywhere?

4) Does your engine have the iridium plugs? Have you replaced them yet?

5) Mainly highway driving, long distance, cold winters and roadsalt where you live?

I too, prefer to do my own regular maintenance and you have just demonstrated that a car can just last as long and be in perfect condition even if you don't visit the dealer for scheduled maintenance on a regular basis.

Also, valve adjustments are much less required now than they once were. Unleaded gas and better oil seem to have helped a lot. Hondas used to require a valve inspection and adjustment every 48000 km (lock nut type). But now, we don't hear much about the necessity of this service. I vividly remember my first motorcycles in the late 70's...

Thanks for sharing your experience with us.

1) I cleaned the valve cover with just plain carb cleaner - it does soften some of the deposits enough for me to remove them (the ones at the top of the valve cover). There are other products that work just as well - but I wanted to make sure that the solvent evaporated away - so carb cleaner was the ticket. Most of the golden color stayed there - so I just left it as is - the others just dissolved away.

 

2) Engine does not drink a drop of oil, even through the extended drain periods. I check the oil the morning before I fill up ~ once a week. But most of my driving (~80%) is highway - city driving happens mostly on the weekends.

3) My UOAs look very good - even the tech commented on how clean the oil was. I have a PDF somewhere. As soon as I find it - I will post it here.

4) Has Iridium plugs - replaced at ~90K.

5) Commute about 80-100 miles a day -mostly highway. Winter weather in the low teens (hardly below 0 F) - roads are generally salted and sanded.

Yes - I agree 100% that routine maintenance performed by the owner can be just as good or better, in some cases, than the dealership. Because I own the car - I'm more likely to take my time and check over small details that the dealership is not interested or paid to do.

This was just to check the condition of my engine on Mobil 1 and OEM filters and to see if valve adjustments were needed (indicated to be inspected in the service manual - usually audible checks are the norm). With all the problems that seem to plague of the 1ZZFE engiens - I just wanted to make sure that mine was not one of them. So far - I'm impressed.

Guest Toyota-san

Excellent write up! Goes to show Mobil1 is the stuff of choice. Glad to see your motor is holding up well and providing you with good service.

Guest goldeneye

With all the problems that seem to plague of the 1ZZFE engiens - I just wanted to make sure that mine was not one of them. So far - I'm impressed.

fishexpo101, since I'm new to 1ZZFE engines, what were (are) some major problems with these engines?

I have an LE05. Do the 2005 models also have the same problems?

Thanks!

Like Ti-Jean mentioned - sticking piston rings, worn valve seals, emission related problems - led to an excessive amount of oil consumption. Most were with conventional oil - switching to synthetics seems to have eliminated some of those problems. Some had them worse than others - might have been something to do with the way the engines were broken in or a manufacturing fluke.

Most of the 9th generation Corollas (2003+) seem to have the oil issues fixed but have their own issues - like cold weather starter grind, ECM program issues, and a few others. Emissions related problems seems to about the same for both generations - but big difference between the average fuel economy for the 9th gen vs 8th gen (1998-2002). The 9th generation generating very impressive MPG numbers. May be do to different ECM programming or engine upgrades.

One thing that bugs me is -- How the heck do you remove the black plastic cover over the engine? I have studied the nuts that hold it down very carefully, and there doesn't seem to be any non-destructive way of removing them. I have asked this Q before -- does anyone have an answer?

Ti-Jean

One thing that bugs me is -- How the heck do you remove the black plastic cover over the engine? I have studied the nuts that hold it down very carefully, and there doesn't seem to be any non-destructive way of removing them. I have asked this Q before -- does anyone have an answer?

You're right, it's tricky do do but I managed to pull it off without breaking anything.

 

I think that there are 2 screws and the other 2, you just pull out.

Ti-Jean is exactly right. Two are bolt heads (10mm) and the other two are plastic plugs. They have little detents on the head and can be grabbed with some needle-nosed pliers. Trick is to pull them off without breaking the clips.

What kind of a motion sequence is required on the detent-like plugs? Describe the exact procedure in infinite detail. I have not been able to move them with pliers without exerting potentially destructive force. I don't want to break them.

The least destructive way to remove them is to unscrew them, like any other bolt, while pulling up slightly. The plugs have plastic "flutes" along their length that hold them tighly in the hole. You could just pull them straight out - but may risk the chance of breaking them off. I just replaced mine with "real" bolts - after I borke both of them off last year.

friendly_jacek

I went ahead and checked vlave clearances on my Corolla and took some pics for good measure (reference for hose locations, etc.)

 

Wanted to take a peeks and see if things were clean or dirty under there - any sludge, deposits, or varnish - and if the valves needed adjustment (somewhat noisy lately).

Photos:

http://photobucket.com/albums/v620/fishexp...djust%20Valves/

The pictures speak for themselves - there was some varnish and slight deposits - but nothing to be worried about. Looking at the valvetrain - everything was pretty clean with very little wear on the cam lobes and lifters. The engine has about 105K miles and is about 5K into the oil change (wanted to do it this late in the change - that way I will change oil soon to help remove any dirt or debris that may have fallen in).

Tips - makes sure to blow out the sparkplug holes before removing the plugs and around the outside of the valvecover to help reduce the possibility of dirt falling in. I used a OEM Toyota gasket - cost me $25 at the stealship. Could have used FelPro or others - but wouldn't have saved any more money - plus fitment could have been an issue. Can't go wrong with OEM gaskets.

I disconnected the wire loom, any brackets attached to the valvecover, removed coilpacks and plugs, and moved everything out of the way that could have prevented the valvecover from coming off.

Most of the bolts were 10mm on the valvecover, coilpack hold downs, and for the wire loom. Need a 19mm socket to put on the crank to turn the crank CW to get it to TDC on cylinder #1 (make sure to match up to 0 degree mark on crank pulley) - compression gauge will help, but you can also verify visually by looking down into the sparkplug holes or putting your finger over the #1 sparkplug hole. Once there - you can use tappet feeler gauges to measure clearances (between camshaft lobe and top of lifter) between the intake and exhaust valves on cylinder #1, intake on #3, and exhaust on #2 - then turn the crank over a full revolution to measure the others.

All said and done - the tolerances on the intake were supposed to be between 0.006-0.010 inches and the exhaust to be between 0.010 and 0.014 inches.

I found that all intake clearances were tighter than 0.007 and exhausts were all on 0.010 or less. Basically - nothing was wrong, valves were all on spec. - engine showed very little wear that was also verified with used oil analysis done yearly (UOA). Chaulk up another good engine to Toyota.

Motor oil used - Mobil 1 synthetic every 7500-8000 miles, OEM filters. Never "babied" the car - daily driver, but made sure all maintenance was on schedule. First 30K services done by dealer (free service promotion on schduled maintenance - I did every other oil change myself) - everything after that was done by myself.

Fish,

sorry to revive this old post (I found it by googling for lifters) but I believe there is an error in the description of the nature of clearance in 1ZZ-FE. I understand that this engine is prone to decreased clearance while the valve wears (sinks into the head). In extreme conditions, the clearance will be too low and the valve will not close leading to burning up or loss of pressure. So, your tight clearance was an evidence of valve wear and you should have loosen them up. Am I incorrect?

If the clearances are excessively tight - then yes, there is a chance that will not close all the way (lifter "rides" the camshaft constantly) and possibly even see some valve float at higher RPMs.

I should have mentioned how tight they actually were, re-reading my description - made it sound like they were not even close to spec. If I stepped down a size in feeler gauge, then I could easily slide the gauge in between the lifter and a camshaft. That meant that my actually clearance was probably at the edge of the spec. The exhausts were the only one that I could measure that were almost too tight by 0.001" - but subsequent checks shown that hasn't changed at all - so I chalk that up to me not trying to shove the feeler gauge in there hard enough. Toyota wouldn't have put that spec on paper unless they know there is a little safety margin built into it, but that might be assuming too much.

As for the excessive valve wear tightening clearance - that is very possible. If the either the face of the valve or valve seat eroded away - that could cause that clearance to tighten up - since the valve sits physically higher up in the head - cause it to push out the lifter, closing up that clearance.

Probably could have adjusted the valves in the middle of the spec and see how they evolved over time, probably should have done that - as that would have been a decent experiment to run. But since compression numbers are still good (leakdown test checks out), fuel economy is good, and no evidence of burned valves (looked at manifold vacuum - no fluctuations or beats in readings to suggest otherwise), engine power and performance are still good - I didn't have a strong enough incentive to adjust them at that time.

Though you make a pretty good point. The car does ping on occasion, even when I bought it new off the lot. If the clearances were tight enough to cause a hot spot on the valve - that could explain the pinging I get from time to time. Running higher octane has resulting in me getting better fuel economy, but also hidden most of the pinging symptoms/issues. But then again, deposits in the combustion chamber can also give you that behavior as well.

Got a leaky timing chain tensioner - car has over 150K miles - so it might be a good excuse to pull the head off and see what it looks like.

friendly_jacek

Got a leaky timing chain tensioner - car has over 150K miles - so it might be a good excuse to pull the head off and see what it looks like.

What are symptoms of that?

Coming back to the lifters, looks like tolerances are staying stable. I guess Toyota figured out a way for keeping tolerances in check, otherwise we would see a lot of problems with Toyota engines over 100,000 miles, as few people check valves these days. I was wondering why Toyota doesn't use hydraulic lifters, but it sounds like solid lifters work OK for Toyota. The only problem I see for a DIY project, if the clearance is off, one needs to remove the lifter (and the cam in the process), measure it and then go and buy a shorter/longer one. A lot a hassle. I will probably not check them before 120,000 miles.

Curious, the VVT-i picture shows a gear with a big cylinder on it. How does that work?

Also, Fish, you're welcome to come fix my car as practice ;-)

What are symptoms of that?

 

Coming back to the lifters, looks like tolerances are staying stable. I guess Toyota figured out a way for keeping tolerances in check, otherwise we would see a lot of problems with Toyota engines over 100,000 miles, as few people check valves these days. I was wondering why Toyota doesn't use hydraulic lifters, but it sounds like solid lifters work OK for Toyota. The only problem I see for a DIY project, if the clearance is off, one needs to remove the lifter (and the cam in the process), measure it and then go and buy a shorter/longer one. A lot a hassle. I will probably not check them before 120,000 miles.

I actually didn't notice it right away, as the leak was pretty slow. Just noticed a wet spot on the back of the head - right where the timing chain tensioner would be - when I giving my a car a good look over. Haven't had a good chance to look at it fully, been pretty busy at work - might be able to take a peek at it this weekend. I'll be sure to post up some pics of the leak and a guide to address it.

 

Yup, as long as the tolerances stay there - I'm not too worried about it. You are correct, that the process of getting the lifter out, measure each one individually, and then ordering new ones to get the clearance in spec is a royal pain. Some have gotten lucky and been able to use one lifter elsewhere on the engine, to bring that clearance to spec - but many were either forced to grind down the ends of the valves. From what I've gathered, these lifters are special order only, guessing that Toyota doesn't expect a huge run on them - so it take a little while to get them.

Curious, the VVT-i picture shows a gear with a big cylinder on it. How does that work?

 

Also, Fish, you're welcome to come fix my car as practice ;-)

That is the VVT-i actuator. Inside that cylinder are some vane like structures that are oil pressure actuated. The one vane that is fixed to the intake camshaft, the other is fixed to the toothed gear driving the chain. Under the right conditions - the oil control valve/solenoid will allow oil pressure to flow through the various passage ways to the end of the intake camshaft to the cam bearing, to the VVT-i actuator on the end. That causes the one "vane" to move relative to the other - advancing the timing or retarding the timing for the conditions at hand.

 

A good description here, on spyderchat.com: http://www.spyderchat.com/enginedetail.htm

A good pic of an open VVT-i actuator, courtesty of newcelica.org: http://www.newcelica.org/photopost/data/500/Dissection02.JPG

Bad_dude

I have a 1999 Corolla VE, 3 speed automatic, would I have to adjust the valves? How do you know if you need to? Any procedure to follow to avoid messing up the car?

Thanks.

How the techs do it is via audible check first. There isn't a spec'd interval where you much adjust the valves - some cases where there is excessive valvetrain noise you will have to check clearances. The 1ZZ-FE is noisy even when running properly. Generally, if the upper valvetrain is making noise, even when the engine is fully warmed up - that might be enough to warrant pulling the valve cover and checking clearances.

If any of the clearances are indeed way off spec - you'll have to pull the camshafts off and remove the bucket shim and replace with a properly sized one. Personally, if I find any clearances that are that much off, at that point, I would just tear the whole engine done and rebuild it - at the very least, rebuild the head.

Bad_dude

How the techs do it is via audible check first. There isn't a spec'd interval where you much adjust the valves - some cases where there is excessive valvetrain noise you will have to check clearances. The 1ZZ-FE is noisy even when running properly. Generally, if the upper valvetrain is making noise, even when the engine is fully warmed up - that might be enough to warrant pulling the valve cover and checking clearances.

 

If any of the clearances are indeed way off spec - you'll have to pull the camshafts off and remove the bucket shim and replace with a properly sized one. Personally, if I find any clearances that are that much off, at that point, I would just tear the whole engine done and rebuild it - at the very least, rebuild the head.

Holly cow! I am just a beginner, I am more familiar with my Accord. I know my needs valve adjustment every 30000 miles or so or when the valves start ticking. But it never had to remove the camshafts and all that. Wow!!

Never the less, I need to replace the valve cover, while under there, I might just well check for clearance. My car only has about 100K miles on it, but what are the specs for the feeler gauges? How do you turn the crank pulley to get to TDC? I know with my Accord, I can turn the power steering pulley and that would turn the crank pulley as well, not sure with the Corolla as the PS pulley is on the bottom. On my Accord, I don't remove the timing cover, but I look at the lobes and they are pointing down then that is where I adjust the valves on that cylinder. I also use the long extension to check for its highest point inside the sparkplugs tube.

I read the Haynes manual and it did not goes too much details about valve adjustments.

Thanks.

There is a big nut on the crank pulley - just pull the spark plugs before you start cranking away at the pulley - makes it a lot easier to do. There are match marks on the intake and exhaust cam gears - you'll see them as you turn the crank pulley. You can also verify by looking at the lobes on the camshafts itself. TDC/compression on piston #1 - look at the match marks, or you can do it old school and shove something inside the sparkplug tube and watch when the piston moves to the highest position (just make sure nothing falls in).

Yeah, this engine design has no jam nuts and screw adjusters to adjust the valve clearance like on older Hondas.

Specs call for acceptable range (cold engine):

Intake 0.15 - 0.25 mm (0.006 - 0.010 in.)

Exhaust 0.25 - 0.35 mm (0.010 - 0.014 in.)

Done in two sets - first find TDC/compression for cylinder #1 (closest to the pulleys)

You can measure clearance on intake/exhaust for cylinder #1, intake on cylinder #2, and exhaust on cylinder #3. Spin the crankshaft 360 degress, this will allow you to check the others - exhaust on cylinder #2, intake on cylinder #3, and intake/exhaust for cylinder #4. Make note of all the clearances measured - even if they are inside spec, for future reference. Just like on other valve clearance checks - you want the feeler gauge to just "drag" inbetween the camshaft and the lifter. Don't want too much slop or so tight you have to jam it forcefully.

If any are way off spec - you'll have to pull the camshafts out of the way to pull the lifter cups out to be replaced. Have to get a micrometer to measure the thickness between the top of the cap and the button on the bottom of the cup.

Hi Fish,

Iwas planning to adjust valve and I came to your article. The only question, Ihave is how turn the crank over a full revolution to measure theothers value.

Thanks



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