Lexus IS300 timing belt and water pump change

The Lexus was due for a new timing belt and water pump so I decided to tackle it on my own and save the $400 or so that I would have paid for labor at one of the local independent shops. (I’m a total DIY’er geek too.) There was a pretty good post about how to do it over at and I just wanted to add a couple comments based on my experiences here.

1. The crank bolt is hard to get off, but all you need is a 22mm deep socket and a big cheater bar if you have a manual transmission. Just put it in 5th gear, pull the emergency brake, and pull really hard. One tip is to wrap a pillow in a garbage bag and put it where your cheater bar might hit the fender in case you aren’t able to stop pulling in time.

2. The timing belt tensioner can be compressed with a bench vise, but make sure you put the pin and rubber seal on the right way. I had it backwards the first time which isn’t apparent until you try to put it back in the car.

3. I marked the old timing belt so I knew how many teeth were between the camshaft gears and the crankshaft gear. That helped me put the new one on correctly the first time. (The second time I wasn’t so lucky… see number nine below.)
timing belt

4. A standard harmonic balancer puller works great to pull the crankshaft pulley. Just make sure you have metric bolts.
crankpulley puller

5. The PCV valve in my car is threaded on. The replacement one I bought has a grommet instead. Make sure you get the right one for your car.

6. You don’t need to pull the power steering pump like it says in the service manual. You just need to remove the power steering pump bracket out of the way so you can access one of the timing belt cover bolts.
pspump bracket

7. I bought the Toyota Extra Long Life coolant. It was friggin’ $23 compared to the Prestone universal kind at $12. I didn’t think it was going to be that much more but oh well… I guess it’s not a big deal if you just change it once every 100,000 miles. (Tip: the parts guys said the “super” long life coolant is the same as the long life, just pre-mixed with water so you don’t have to dilute it yourself.)

8. Make sure you engage the number 2 water bypass pipe when you install the water pump. I missed it the first time and didn’t realize it until I was almost done buttoning it up and realized I had 2 extra nuts that didn’t have a home. Doh! That really sucked as I had to tear everything apart to fix the problem.
water bypass

9. Make sure your timing belt position stays true after you release the tensioner. (I would release the tensioner before you put anything back on and count the teeth between pulleys again.) I had thought everything was fine until I put the crank pulley back on and found out that I was off by a tooth. Doh! Had to take a few steps back (again) as a result.

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19 Responses to Lexus IS300 timing belt and water pump change

  1. Pingback: my.IS - Lexus IS Forum - DIY: TIMING BELT & WATER PUMP also includes Serpentine Belt

  2. Charles says:

    i know this entry is over a year old, but can you please post up the part numbers for all the parts that were necessary for this job. that would be REALLY helpful for me and anybody else who may stumble upon this page in the future.

  3. jason says:

    Here’s a post that has the part numbers:

    I didn’t order my stuff from Toyota, I got mine from but I can’t find the receipt right now. If I find it, I’ll post it here.

    – 5-6 HRS

    – 10mm Socket Wrench
    – Breaker Bar
    – Chain Wrench
    – Modified 10mm Wrench

    – Timing Belt: Part No. 13568-49036
    – Tentioner: Part No. 13540-46030
    – Idler: Part No. 13505-46041
    – Drive Belt: Part No. 99366-D1930
    – Water Pump: Part No. 16100-49876-83
    – T/Stat: Part No. 90916-03093
    – T/Stat Gasket: Part No. 16325-62010
    – PCV 5/2000-5/2001: Part No. 12204-46030
    – PCV 5/2001 and up: Part No. 12204-46031
    – PCV Grommet: Part No. 90480-18001
    – O-Rings Bypass Pipe: Part No. 96761-24022 (Qty=2)
    – O-Ring Bypass Outlet: Part No. 96761-24028

  4. Bustercherry86 says:

    Is changing the IS300 belt the same as the Altezza ? cant find a walk through for the Altezza.

  5. jason says:

    I think the Altezza is just the JDM IS300 except that the US didn’t get the 2 liter version. So if you have a 3.0 liter Altezza, I think it’s the same.

  6. Jessie says:

    My 2003 IS300 is just hitting the 60,000 Miles Marker and the dealership is advising that I change my timing belt. Is that too soon?

  7. jason says:

    Unless there’s some special reason (prematurely frayed belt, bad pulley/bearing or something like that), I don’t see why you would do it prior to the factory manual recommendation. My feeling is that the dealer just wants your money. My belt still looked great after I took it off with 100,000 miles. Of course, it wouldn’t hurt to do it early, but it’s a significant expense to take on for no good reason. Whenever you do it, make sure you replace the water pump as well since all the labor to take the timing belt off needs to be done to remove the water pump anyway.

  8. Phuong Le says:

    Thanks for posting the detailed instruction to change a is300 timing belt…..think I will do it…maybe save myself some $$$.

  9. Mike says:

    Where I can find the cranckshaft pulley tool??

  10. jason says:

    You actually don’t need the tool. Just a big cheater bar and the appropriate sized deep socket will do. What you will need to do though, is set the car in low gear and crank on the e-brake so the wheels-tranny can keep the engine from turning as you try to loosen the bolt. Also, keep a pillow on the fender in case it comes loose suddenly so you don’t dent anything.

    EDIT: If you were referring to the tool to pull the crankshaft pulley off, you can go to a Kragen or any parts store and borrow theirs.

  11. toots says:

    Where is the timing belt found in a altezza manual, which I assume is the same as the IS300

  12. jason says:

    Assuming you have the six cylinder and not the four cylinder, I would imagine it’s exactly the same.

  13. jose says:

    you only needed a 10mm wrench to remove all the components in front of the timing belt??

  14. jose says:

    I am pretty handy as I’ve worked on cars before as a mechanic but I have never done a timing belt on this car. my problem is all the tools I own are at my job location and I want to do the belt at home. so I have no idea what tools to take home. I don’t want to start the job with limited tools and then get stuck because a tool I need is at my job. so could you make a complete list of tools I need if that’s possible?

  15. jason says:

    It’s been too long, sorry. I would not recommend it anyway. Hard to say what tool you may “need” last minute if you get in a bind.

  16. jason says:

    I don’t remember for sure. I think you probably need a screwdriver too. But as in the previous comment, would be risky to try to limit yourself on the tools available.

  17. Sam says:

    I’m only changing the water pump do I have to mess with any of the timing belt components???

  18. jason says:

    you don’t have to. but you might as well since you’re there. it’s easy and the parts are cheap. it’s kinda auto rule #1. when you change either the water pump or the timing belt, do the other one too.

  19. joemama says:

    easy way to loosen crank bolt , put breaker bar on bolt spin starter be sure to cover radiator with piece of plywood.. been doin that way for 4o years 80 percent sucess exept on hondas

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