digger08

iTrader: (1)

In Canada...... Lexus lists this as an "Audible" inspection only? Am I missing something deep inside of the service manual?

Metric conversion 60K is 96 Km's

lobuxracer

iTrader: (2)

I didn't see any procedure in the manual for audibly "testing" the valve clearance. With all the noise from the DI injectors, it seems to me it would be very challenging to hear loose valves unless the looseness is extreme.

digger08

iTrader: (1)

LOL

........Obviously Lexus of Canada disagrees with your analysis, thus printing the words "Audibly" in their service maintenance information posted on-line for all of their IS F owners to view across the land. As this differs from the USA version, I have no idea why.

IMO - I am perfectly fine with not having my engine torn apart voluntarily, loosing my car for 4 days at the dealer, and handing over $2k, because I forced the issue on a 60K inspection.

I would need to see a more concrete reason or answer from Lexus on the necessity of this, before performing this work. I would be shocked to find North America Lexus dealers voluntarily performing this service without a valid reason or engine failure.

Till someone proves otherwise, I will keep my money in my pocket.

itsmike177

iTrader: (3)

I agree with digger08; I will be forgoing the valve inspection service on the 08 ISF when 60k rolls around. I called 2 local Lexus dealers here in Southern CA for price quotes and one did not even know what it was, so enough said. Other dealer quoted $1200 for the 60k maintenance package which included spark plugs and all the "checks."

If a service dealer does not even know what it is, I definitely won't be bringing in the car to have them tear down the engine just to "check" something that most likely is within spec. I suppose the days of Toyota engines running to 150k without these extraneous precautions and checks are over.

lobuxracer

iTrader: (2)

This has nothing to do with quality. Yamaha made a choice not to run hydraulic lash adjusters. They also chose not to make the adjustment easy with simple tools despite the 32 rocker arms in the heads.

In my motorcycle days, this was considered par for the course - except the inspection interval was 5k miles.

This isn't even close to an engine tear down. It's just a PITA because the valve covers have to come off.

Finally, there's a sign in my dad's garage - REAL engines have solid lifters. So, they went this route, built a very reliable and powerful engine without being concerned about valve lash issues for 60k miles. I'm betting I'll find nothing out of spec (just like my Supra), but things happen over time, and titanium isn't steel, so there are lots of possibilities. I'm still going to do it, mostly because I don't want a valve dropping at a track day. Getting home would really suck.

spddemon

I feel Yamaha choose Ti valves for reason strength and durability. IMO I do not see these bending unless this car is misused or modified with turbos and superchargers or even nitrous. I would bet your not going to have to adjust anything. With all the Toyota and Lexus cars in all of are families no one has ever had this done.

lobuxracer

iTrader: (2)

No, they were not chosen for strength and durability. They're light. Very light and very expensive. Ti does some things very well, and others not so well. It doesn't bend and that's not the concern with lash, the concern is going too tight and burning. AMHIK.

lobuxracer

iTrader: (2)

Tonight was the end of a weekend effort. Some small things turned into massive issues, but all in all, persistence prevailed and the task was completed successfully.

Took some pics, but there's really not a lot to see - more disassembly than I originally thought, but a LOT less than what Lexus says you need to do.

The good news? All valves were within specification. I use a go/no-go methodology which means first I test with the minimum specification, then I test with 0.001" over the maximum specification. If minimum clears and maximum +0.001" does not, we're good to go. As a wise engine builder told me years ago, "a loose valve is a happy valve." Translation - if you have more than minimum clearance, life isn't bad. If you have more than maximum clearance, you need to do a top end run, then check again. Valves don't grow, so more than maximum usually means carbon build up which goes away when you put a good load on the engine.

Anyway, I'll post the pictures later, and I want to give a shout out to LEXUS (BOO!!! Your wiring harness clamps SUCK BIG TIME and now I know why dealership techs just cut your junk off and leave the harness loose!!) and to my good friend Ben who slaved with me through the whole project despite the sub-freezing temperatures outside and in the garage.

g35cali

iTrader: (5)

Thats great news that everthing was within specs and i take it since you track the car you may push the car alot harder than the majority of owners here...looking forward to the pics of the teardown

john09ISF

Now that you have done it and know what's involved, how long should it take an experienced tech to perform this service?

In case I want to have someone do this when the time comes, I am curious to know how much it should cost.

lobuxracer

iTrader: (2)

About 4 hours. After everything I learned, I could do it again fairly quickly. The only thing I really want to do before the next inspection is find some stud mounted wiring harness clips so I can just cut off the ones Lexus put on and replace them with something I can either easily remove or inexpensively replace. It was the biggest impediment to getting the job done quickly, primarily because I did not want to damage them.

lobuxracer

iTrader: (2)

To get this thing started, you'll have to first remove all the underhood plastic and the engine undertray. Why the undertray? Because you're going to drop things and you're way better off if they fall to the floor than trying to fish them off the undertray. AMHIK.

You will be disconnecting your battery and you'll be removing the ECM and TCU along with the box holding them in place. Expect your AVG MPG to go back to zero, and if you don't put power to the car to retain all the memory settings, you'll be reinitializing the windows, the seat positions, any keys paired to the seat positions, and your navigation firmware.

There is a lot to do and a few tricks to save some grief. Lexus says you have remove everything from the top of the engine. The flat rate mechanic in me says, no way am I taking off the intake manifold just to remove the valve covers. And so it began...

First things first, you have to discharge the fuel pressure before you spray gasoline all over your garage. To do this, remove the fuel pump relay and disconnect the fuel pump resistor. See pics below -



Relay removed -



Fuel pump resistor disconnected -



Up close -



Start the engine and let it run until it dies. Try to start the engine again, and notice it keeps cranking as long as you keep your foot on the brake. When the engine refuses to start with a good 5 second crank, you're ready to start the real work. Now it's time to start taking lots of stuff off the valve covers. The wiring harnesses are the worst part of this. They have these little stud mounted retaining devices



holding the harnes in place like this one on the front of bank 1's valve cover



I wasted many hours trying to remove these clips without breaking them. I now know why dealership techs just cut them and call it a day. Even after modifying a snap ring too to fit over the 6mm studs and engage the two ears to spread them as wide as possible, the clips still would not come off the studs. It ended up being easier to just release the retainer for the strap and unscrew the mount from the stud. So, once you get the harnesses off the covers, you quickly realize the main harness will have to move. This means you need to completely disassemble the ECM, TCU, and the wires going to and from these devices. When you're done, it looks like this





Move the main harness out of the way like this



On the other side, you'll need to unbolt the dipstick (no need to remove it though), remove the battery and the bracket holding the engine side of the fuse box. It's easier to move the battery box if you remove the bolts for the steering ECU, but there is no need to remove this ECU.





There is a black plastic shroud around both high pressure fuel pumps. It has sound deadening material in it. It just unsnaps and reveals the HPFP





The bank 1 and bank 2 pumps are slightly different. Don't mix them up or you'll really be scratching your head thinking WTF? Remove the fuel lines on the bank 1 (driver's) side. They have retainer clips - the black one covers two lines. It snaps off. Squeeze the two blue buttons and pull gently on the line to remove. It really is that easy! On the other end, there are two orange retainers. Slide them back only a little - just enough to expose the blue buttons - then squeeze the blue buttons to release the hoses.

To remove the pumps, first remove the rubber fuel line, then the fuel pulsation damper. The damper has a 22mm nut on it and a hat shaped top. It's a typical banjo connection with two metal washers Toyota says must be replaced on principle. That means four washers - but I didn't buy those washers, I just re-used the existing ones and they worked fine. Next time I'll put them on my parts list. After the fuel pulsation damper is removed, you'll need to disconnect the 21mm flare nut from the top of the pump. CAUTION - IF YOU LOOSEN THE LOWER NUT ON THE HPFP, LEXUS SAYS YOU MUST REPLACE THE ENTIRE PUMP! So hold the lower portion with a wrench while you loosen the flare nut. When you remove this, you'll see the line doesn't really disengage much. If you remove the bolts holding the fuel lines down (they're right next to the fuel pumps) the lines will move enough to get sufficient slack to remove the pump. Really. Now remove the two nuts holding the pumps down, and the unit will slide off the studs.

Next, prove you're smarter than I was by removing the studs like this. You can try to do this with a Torx socket per the FSM, but when I tried I was not at all successful.





Do this BEFORE you remove the valve covers. Trust me, you would thank me for this small piece of information if you ever tried to do this with the studs in place. AMHIK.

At this point you should have most of the stuff in the way of removing the valve covers off. There are three long studs in the center of each of the valve covers (only Lexus knows why these things have a stud sticking up from them, but they do). Each of these has a washer with a captive 0-ring, and after my 2JZ experiences with similar washers, I made sure I had them on hand to replace. It wasn't essential. The washers were still very soft and pliable, unlike the glassy hard metal/rubber washers on 2JZ valve covers. I could have reused them without fear. Now remove the 13 6mm screws (10mm heads) holding the valve covers in place. Lift off the valve covers and you'll see what you came for - four cams, thirty two valves and rocker arms.



When you flip the valve cover over, you will immediately be able to see if your oil change interval has been sufficient. If you've gone too long, it will be covered with the brown death. Mine, despite the 12k mile OCI is still clean and fresh looking. Very slight varnish tells me this engine is not unhappy!



Now it's time to get measuring. If you didn't remove the sparkplugs when you removed the coils (what were you thinking? You need to do plugs at 60k too...) Rotate the engine to TDC (zero mark on the damper) and check for the alignment marks on the bank 1 cams. They will be pointing up if you are at TDC with the #1 cylinder on the intake stroke. That's where you want to start.

INSPECTION STANDARD - Intake 0.12mm to 0.18mm (0.005" to 0.007") Exhaust 0.22mm to 0.28mm (0.009" to 0.011")

Check #1 intake and exhaust, #3 exhaust, #5 intake, and #7 exhaust on bank 1. Check #2 intake, #4 intake, and #8 exhaust. The way I do this is pretty simple - start with the thinnest measurement and make sure the feeler gauge will easily slide between the cam and the rocker (yes, this spec is for cam to rocker clearance, NOT rocker arm to valve clearance!). This ensures I have at least the minimum gap. Then I take a feeler gauge at the thick end, add 0.001" (so I used 0.008" for the intake and 0.012" for the exhaust) and make sure it will NOT clear the cam and roller. It's what I call go/no go valve clearance checking. The exact measurement is academic. You only care that there is enough clearance so you won't burn a valve and the rocker arms don't clatter when the engine is running. It looks like this:









Now rotate the crank 360 degrees and check #3 intake, #5 Exhaust, and #7 intake on bank 1, and #2 exhaust, #4 exhaust, #6 intake and exhaust, finally #8 intake and you're done. Hopefully they're all in specification. Mine were. To adjust if the clearances are not right, Lexus says you have to remove the cams. I have my doubts about this, I'm pretty sure I could figure out a way to get the valve depressed enough and held down to remove and replace the shim. 2JZ engines are WAY easier in this respect unless someone swapped out the buckets for shim under bucket - then you have to remove the cams with the 2JZ too. Anyway...now that we've measured and come to grips with not having to adjust anything, it's time to install the sparkplugs. What? Plugs now? Yes, you have a lot shallower hole to deal with and the likelihood of closing the gap if you drop a plug in the hole is a lot smaller.

One other thing before we button things back up. There is an oil filter in each of the valve covers. It is a tiny stainless steel screen intended to prevent damage to the oil control solenoid and the oil operated cam sprocket for the exhaust valve. Replacing it is pretty cheap, so I bought them and replaced them. See below





It was completely unnecessary. The filters were perfectly clean even with track use and 12k mile OCI. Which brings up another thing - I bought a whole load of seals, o-rings, and even valve cover gaskets with the expectation the ones on the car would be brittle from heat and need to be replaced. I was wrong. Every single seal was still soft and pliable, easily reuseable. Still there were two other seals I replaced besides the mini oil filter and the valve cover washers - they go between the cam cap and the valve cover for the oil control valve to operate the exhaust cam timing gear.



Seals in place



Despite these being still in perfect shape, I replaced them because I had them. I did not replace the valve cover gaskets, the fuel pump spacer gaskets, the sparkplug tube gaskets, or a bunch of other small seals because there was no point in it.

If I were doing this again on a 60k mile car, I'd probably just buy the sparkplugs and the 6 washers, Lexus part number 90210-08045. Nothing else needed to be replaced, so I'm saving it for the 120k mile check when the seals will definitely be older and harder.

Button everything up the way it came apart. If you need the torque specs for the fuel pump or valve covers ask and I'll post details. I suspect anyone else chosing to do this themselves will likely not need this info from me.

This is not a task for the first time mechanic. If you've never done something like this yourself, find someone who has and get them to help you. It will be invaluable.

Last but not least, you're going to drop bolts. Be sure you have a long extension magnet to fish for bolts (and nuts) that slip out of your latex gloved but oily hands.

hahahaf

iTrader: (2)

great write up lobux
thanks for taking the time

Joe Z

iTrader: (10)

Thanks Lance... I will be skipping this as a DIY project..

MRxSLAYx

Anyone know hw to remove the fuel relay. Need help asap