kjcole

Just did my timing belt over the weekend. Agree that it is a straightforward job if you are used to working on your own stuff. This thread was a great help, as were the PDF's earlier in this thread. I bought that tool for holding the harmonic damper pulley (Schley product) and it was well worth it. That tool, two breaker bars and two 4 ft pieces of black pipe for leverage and the crank pulley bolt released without complaint.

The only problem I had was the connector for the cam position sensor (left, that is, driver's side cam) wouldn't release from it's holder and so it was too big to pass through the hole in the cover. I had to unbolt the cam position sensor and took out the cover and sensor together. No big deal but I wasted 20 minutes trying to get that connector to release.

I removed and installed the timing belt at 50 ATDC - piece of cake - even with one person. The cams stayed put and the belt slipped in dead on the marks without having to wiggle/jiggle the cams by 1 tooth or 1/2 tooth, etc as suggested by the manual. You don't need that SST for moving the cams or anything ----- unless you are overhauling the cams ---- read on.

It went so easy that I couldn't understand why the service manual specified removing the belt at 50 ATDC, and then specify rotating everything to TDC to install the timing belt (where the left cam is under load to jump, etc) requiring a special tool for rotating/holding the cams, blah, blah. Makes absolutely no sense to insert a step that is simply not needed, except for the fact that there is no mark on the oil pump housing for setting the crank at 50 ATDC. I'll go on record emphatically stating to ignore the service manual when it says to rotate back to TDC just to install the belt. (Of course, to be safe make sure you set everything at 50 ATDC dead on -as per the cam markings- before removing the belt and then don't move the crank. Although I didn't paint marks on the crank and oil pump housing for 50 ATDC, that would ensure that the belt would install easily.)

momssc

How many miles/years were on your old belt and what did it look like?

kjcole

2002 with 92,700 miles. Texas car for nearly all its life.

Belt looked great. No visible signs of breakdown (no missing teeth, teeth were still sharp, etc). (BTW, compared to the timing belt on Audi/VW's these are wide Tbelts). Hydraulic tensioner was still strong, Tbelt tension and idler pulleys were smooth, water pump bearings were smooth and impeller looked great (I replaced all with new OEM anyway), plus all serpentine belt pulleys and idler bearings felt smooth. . The harmonic damper/crank pulley slid off the crank with no effort, which surprised me (no corrosion or surface rust on the mating surfaces). Only issue that I found was the radiator cap - the spring and seal mechanism had broke apart so I had to fish the spring and a few small parts out of the radiator. (BTW, I highly recommend the extra 30 minutes to remove the radiator/fan assembly. Simple operation and the extra working space is great since you are spending so much time on that engine's frontal plane).

I suspect that this collection of parts could have gone another 30-50K, but I wouldn't have enjoyed any of it with the worry of destroying such a fabulous engine. I also have to say that I've worked on Audi's and Mercedes that I've owned in the past, and this Toyota/Lexus V8 is impressive. I haven't discovered any of those quirky things that make a repair job tough and have you asking 'what were those engineers/designers thinking?"

Kelly

greywolf40

Great information here, I used some of it in putting together a video walkthrough for changing the timing belt on the LS430, which is very similar. Here is a link:
I hope someone finds it helpful!

joecal

Thanks for all this great information. Inspired to do the timing belt at 98K. Ordered the parts through ebay- $210 for OEM vs $485 from lexuspartsnow.com I will let you know how it goes. Like CJ, ME background with Engineering- little tinkering since college, but remember well.

joecal

I just did my timing belt and water pump over the weekend and it went great! I would have NEVER attempted it with out the help of this club and especially the posts of PEARLPOWER, CJS18 and KJCOLE and moderator. Thank you!! You guys rock!

At 98,000 miles I knew I had to bite the bullet and get it done by the dealer because I had hardly turned a wrench for 23 years since the college days. (CJS particularly inspired me to take action because we were both ME's by nature and he pulled it off with grace)

Some notes:

Once I finally decided to take the time pressure off, and not try to keep up with the pros' 4 hour times I enjoyed the process much more and was less stressed. I took a leisurely 8-9 hours to do the belt and the pump and tensioner parts job.

The Crank pulley nut was a cinch with the special tool, a 2 foot breaker bar and 18" breaker bar w 4' pipe. (CJS and KJCOLE) The pulley slid off like a glove and no rust thanks to California weather. The special pully holding tool was great and also served as a means to rotate the crank later without having to use the nut. (the tool and the pulley attached together acted as a single tool to turn the crank when needed. It could be used then removed from the crank out of the way when not needed)

The plug on the timing belt cover was a pain, just like described. I missed this in the post but willfully ended up cutting 1/8" of the arrowhead snapper off with a Dremel tool and epoxied it back later into the hole in the timing cover.

KJCOLE saved me at least an hour of stress. Using 50 ATDC for taking off the belt and putting on the new belt was smooth, if non-conventional. No movement whatsoever and easy as pie. Just make sure to do the TDC checks diligently, including the oil pump mark, before going to 50 ATDC. Then bring back to to TDC after the new belt is on-doing this by hand nearly 2 more revolutions. Once this step was done there was a huge feeling of relief and the rest was more fun.

I am guessing LEXUS uses their strict TDC method (with the cams loaded) to standardize the proceedure and keep confusion to a minimum in their organization with hundreds of mechanics).


Removing the spring loaded tensioner makes taking off and putting on the belt a snap without moving the cams. Even with the tensioner compressed and held with the pin there may not be enough slack to take the belt off and put the new one on. The tensioner pully will retract even more by when the tensioner is unbolted from the engine. (CJS notes which I missed, but figured out by trial and error)


I can't thank the people enough who have put this site together. I will say that I appreciate this car more than ever (which I bought new 8 years ago)!! Getting familiarized with this jewel of an engine for 8 hours and its beautiful engineering has made me want to keep this car forever! I really believe now that it is one the best production cars made in the world.

barrelrace

My car is not firing on 2,4,6, or 8. The shop said it was a timing belt and may as well do the water pump. I took this to a friend of mine who helped me pull the covers and set the timing with the marks on the pulleys to the timing marks at tdc. At some point, he started to check for voltage at the efi plugs and the car went dead. 4 hours later at Beck's Electric in Austin, the car cranked, but still no fire on the same cylinders and they wanted to change the timing belt. Seemed one side was at 130psi and the other 135psi. They then proceeded to quote me another $900 for the timing belt kit and water pump.

When we looked at the timing belt (my car as 150k miles on it), it seemed really good.

Why not reset the timing?

Could timing be off as to stop 4 cylinders?

I have researched your posts and will have it towed home to verify the mark's alignments.

I am wondering if the timing might be secondary to an elec problem.

Can't find a link on any other engine firing on only one side.

R6extreme

Ok so you told us how to get TDC of the 2 cam locations and the crank position at TDC I get all that but I'm a little deeper than a cam belt as I was a dumbass and waited about 1 week too long to do mine belt and pulleys. Lesson learned but how do you get your exhaust cams to TDC. I can't find this anywhere to be found. I've had my head rebuilt after a bent valve. I replaced all the pulleys for the cam belt, water pump - check, new serpentine just because I had it out might as well and I'm ready to torque the cams back into place and drive my sc again soon. I need some help as I don't see a TDC mark on the 2 other cams. I may have missed as I was a little tired after tear down and reassembly of this. Any help either post here or email me at michaelrmoore75@gmail.com. Thanks

joecal

Sounds like you are deeper than just a timing belt. Over my head but the guys on this site should know. Take your time and Good Luck

R6extreme

Boom! After many websites searching for tips and all data.com I finally got everything I needed to complete my entire top end rebuild. To align the secondary cams there are 2 marks on those cams that align to the primary cam. These can only be seen from the firewall looking forward. There are single dot marks and double dot marks. The single dot marks are at TDC and should be aligned tooth for tooth on the top cam to lower cam. The upper or main cam has a dot at the top of the tooth and the lower cam has the dot in the groove. These have to match. When all lined up and belt installed the double dots should line up at 180deg. To TDC. Hope this helps anyone else that needs it. If you need more info let me know. I know way more about my motor than ever wanted to before.

sebtown

After many worries I finally had the timing belt on my early 2002 SC replaced today due to age (over due by 50 %) not mileage at only 69k. The belt was almost 12 years old. I asked my mechanic to save it so I could take a look. Overall the belt looked pretty good but there were a couple of places where looking at the side of the belt the cord was starting to shred. I will drive and sleep easier now that I have had this service completed.

momssc

Can you get pics of the belt?

kjcole

My 10 year old belt looked great last year. My opinion is that a lot of 'belt' failures often can be traced to failing bearings in the pulleys, and/or the hydraulic tensioner, and/or the water pump bearing. So think about the entire belt path system, and not just whether the belt looks good, when debating if it is time to 'change the timing belt.'

What that said, the algorithm for rubber deterioration is time/distance, and I wouldn't hesitate to start changing belts and hoses after a decade, regardless of mileage. I wouldn't bother with changing pulleys etc on a low mileage older vehicle, however, as the time factor is much less important than the mileage factor on mechanical items like those. Also consider how the car has been driven (lot's of sudden loading on the belt path for an aggressive driving history may cause you to not push the recommended intervals, especially if the car will continue to be driven that way). And in the end the exact time you do the job, and which parts you replace, come down to how much risk you choose to take, rather than some magic formula.

Kelly

sixonemale

This also seems very valid for the predicted life expectancy of a timing belt"

"Life expectancy of the timing belt depends on many factors other than just mileage and age: (1) Weather plays a very important role, rubber tends to get hard and stiff when it's cold, with initial startup under this condition being very hard on the belt. If the vehicle is operated in warmer climate condition the timing belt will last significantly longer than a cold climate. if the vehicle was driven in a cold climate condition but kept indoors when not in use, initial startup will also be less severe, thus belt will last much longer; (2) Driving habits - the timing belt is under greatest stress at initial startup when the belt is cold and stiff. The belt is also under greatest load at the initial crank and initial pick up or acceleration, therefore life expectancy can greatly differ comparing a vehicle that is driven in the city as opposed to vehicle that is operating mostly on highway. The timing belt is under greatest load at initial acceleration and hard acceleration, which will put more tension on the belt causing it to stretch and fatigue thus shorten the belt's life; and (3) Contamination with oil and coolant on the timing belt can greatly affect life expectancy of the timing belt."

With that said, I will be conservative when replacing the timing belt on the SC's interference engine design.

SC43052

+1
Your opinion happens to be fact. I have never heard of, or talked to anyone in the Toyota world who has ever heard of a timing belt breaking on its own. It is always the failure of another component that takes the belt out.

I have heard of some dealers examining the water pump to decide if they should change it or not. Absurd. Toyota does a very good job of designing and sourcing components for longevity, but no water pump will last for ever. If you don't change the pump at 90K miles when are you going to do it? 180K miles when the belt needs to be changed again?

The big dollars (your time or your mechanic's) is getting into the engine. Once you have the timing belt off, the extra work and cost to change the water pump and other belt guide components is insignificant in the big scheme of things.

Replace it all when the engine is open, and for the little extra cost you will sleep better.