step-by-step timing belt replacement LS430
06-26-20, 08:46 AM
#136
06-26-20, 12:07 PM
#138
Not necessarily, but you were being very pro-active!
The service manual recommends the TB change at the 90k mile service. Rubber degrades over time especially in extreme temperatures, so doing yours after a decade of wear (even at low miles) could be a good preventative measure for peace of mind if you were concerned.
I haven't really heard any stories of these belts degrading or breaking until well over 100k miles though. Mine still looked brand new after 12 years and 90k miles.
The service manual recommends the TB change at the 90k mile service. Rubber degrades over time especially in extreme temperatures, so doing yours after a decade of wear (even at low miles) could be a good preventative measure for peace of mind if you were concerned.
I haven't really heard any stories of these belts degrading or breaking until well over 100k miles though. Mine still looked brand new after 12 years and 90k miles.
06-26-20, 12:15 PM
#139
Intermediate
Not necessarily, but you were being very pro-active!
The service manual recommends the TB change at the 90k mile service. Rubber degrades over time especially in extreme temperatures, so doing yours after a decade of wear (even at low miles) could be a good preventative measure for peace of mind if you were concerned.
I haven't really heard any stories of these belts degrading or breaking until well over 100k miles though. Mine still looked brand new after 12 years and 90k miles.
The service manual recommends the TB change at the 90k mile service. Rubber degrades over time especially in extreme temperatures, so doing yours after a decade of wear (even at low miles) could be a good preventative measure for peace of mind if you were concerned.
I haven't really heard any stories of these belts degrading or breaking until well over 100k miles though. Mine still looked brand new after 12 years and 90k miles.
06-26-20, 12:44 PM
#141
Intermediate
I got it from here:
https://us.lexusownersclub.com/forum...-age-or-miles/
third post I saw:
Quote:
Changed my original 98 LS400 @ 94k and 12 years. The belt looked tired but not in imminent danger of breaking. I did quiz a Lexus mechanic about when I should change it and he said 90k miles. He did not even consider the time period. My current 02 LS430 is at 36k and nearly 10 years...still on the original belt and I have no intentions of changing it just yet. And I sleep fine at night. Much more critical is the water pump as Jim mentioned. If that part freezes up, its bye-bye belt, instantly. You should have the coolant changed every 3-5 yrs to keep the pump seals happy.
https://us.lexusownersclub.com/forum...-age-or-miles/
third post I saw:
Quote:
Changed my original 98 LS400 @ 94k and 12 years. The belt looked tired but not in imminent danger of breaking. I did quiz a Lexus mechanic about when I should change it and he said 90k miles. He did not even consider the time period. My current 02 LS430 is at 36k and nearly 10 years...still on the original belt and I have no intentions of changing it just yet. And I sleep fine at night. Much more critical is the water pump as Jim mentioned. If that part freezes up, its bye-bye belt, instantly. You should have the coolant changed every 3-5 yrs to keep the pump seals happy.
06-26-20, 12:49 PM
#142
I got it from here:
https://us.lexusownersclub.com/forum...-age-or-miles/
third post I saw:
Quote:
Changed my original 98 LS400 @ 94k and 12 years. The belt looked tired but not in imminent danger of breaking. I did quiz a Lexus mechanic about when I should change it and he said 90k miles. He did not even consider the time period. My current 02 LS430 is at 36k and nearly 10 years...still on the original belt and I have no intentions of changing it just yet. And I sleep fine at night. Much more critical is the water pump as Jim mentioned. If that part freezes up, its bye-bye belt, instantly. You should have the coolant changed every 3-5 yrs to keep the pump seals happy.
https://us.lexusownersclub.com/forum...-age-or-miles/
third post I saw:
Quote:
Changed my original 98 LS400 @ 94k and 12 years. The belt looked tired but not in imminent danger of breaking. I did quiz a Lexus mechanic about when I should change it and he said 90k miles. He did not even consider the time period. My current 02 LS430 is at 36k and nearly 10 years...still on the original belt and I have no intentions of changing it just yet. And I sleep fine at night. Much more critical is the water pump as Jim mentioned. If that part freezes up, its bye-bye belt, instantly. You should have the coolant changed every 3-5 yrs to keep the pump seals happy.
Sounds technically possible but I'm not sure that qualifies as 'stories of water pumps causing belts to snap'... its not something I've personally ever heard of happening, and would not lose sleep over it
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whenagain (06-26-20)
03-20-21, 07:01 AM
#143
Can anyone speak to the longevity of the Aisin kit? Did you get around 100K out of it? I'm at 125K and 8 years on my Toyota components since the last change and I'm about to do the job. I actually ordered both the Toyota parts and the Aisin kit so I will compare quality and then decide. I understand the Aisin components are all the same manufacturer as Toyota but I'm not 100% convinced it's the same quality.
03-20-21, 09:26 AM
#144
Moderator
Can anyone speak to the longevity of the Aisin kit? Did you get around 100K out of it? I'm at 125K and 8 years on my Toyota components since the last change and I'm about to do the job. I actually ordered both the Toyota parts and the Aisin kit so I will compare quality and then decide. I understand the Aisin components are all the same manufacturer as Toyota but I'm not 100% convinced it's the same quality.
The Aisin kit has a solid reputation. It’s the TB kit of choice for a large majority of forum members. The individual parts are very close to OE quality but there is a reason the entire kit can be purchased for under $200. The KOYO bearings are top notch, the belt is made by Mitsuboshi but not exactly the same as a Mitsuboshi belt purchased from a Lexus dealer. I’ve used the kit with no issue whatsoever but always felt a bit leary about the quality of the water pump. That said I used a Toyota WP on my most recent TB service. If your main concern is deciding between Aisin and genuine Toyota parts you’re in a pretty good spot.
03-21-21, 09:34 AM
#145
Compared the Aisin kit to the Toyota parts today. The waterpump is a little different in the back and has a better finish to it. The Toyota belt was made in USA with green markings vs Mitsuboshi made in Japan. Toyota feels more supple and rubbery and the timing markings are printed better. The two Koyo idlers seem identical, same brand and markings for both. The tensioners are both NTN, the Toyota one says NTN 30 and the Aisin kit says NTN 28 but they look the same. I think next time I would order the belt and pump from Toyota and get the Koyo idlers and NTN tensioner somewhere else as those are exactly the same but at least twice as expensive from Toyota.
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NLLex (03-21-21)
03-29-21, 10:55 AM
#146
Finished my TB this week, after about 20 hours of work over several days. This is a doable task, even for a mediocre tech. Here’s what I learned:
a. I bagged and labeled all fasteners by major assemblies (water pump, tensioner, covers, etc.). This makes reassembly so much easier.
b. Ordered the TKT021 kit from RockAuto, probably a bit more expensive than elsewhere but no issues with fakes.
c. Most important part of the job is the actual belt removal and reinstallation, and it’s easy to get confused by all the info out there. Here’s what worked for me:
d. Get engine to TDC first, using marks on both cams and crank. The crank will show as 0 degrees. All three will match up. If not, turn crank clockwise until they do.
e. Mark the installed belt and spots on the cams/crank.
f. THEN, turn crank clockwise to 50 degrees mark. Crank will line up with the “pin”, and cams will line up with the “T” marks.
g. Remove the belt by loosening the tensioner. Since you are at 50 degrees there is no pressure on either of the cams to rotate as the belt is removed.
h. Transfer marks from old belt to new belt. Double check this, and again carefully line up all the belt teeth on the two belts.
i. Install new belt, beginning at crank, moving to left cam, then right cam. You really have to pull on that belt to get the marks to match up but they will.
j. Fit the tensioner and gradually tighten those two bolts holding it to the engine block. You’ll feel the belt gradually tighten. Check your 3 marks to make sure they are still line up, then remove the pin holding the tensioner hydraulic compressed. No drama.
k. You’re home free at this point.
l. Strongly suggest use of a torque wrench…many of the fasteners are at 13 ft lbs going into rather soft aluminum. Easy to overtighten and strip things.
m. I did spark plugs, PCV valve, thermostat at same time, drained both sides of engine block of coolant. Might as well.
n. correct tools are really important--i used hose pliers, clamps, usual sockets/ratchets/extensions. My tired 1/2 inch Husky impact got the crank bolt off easily. No need for a puller on the crank dampener, it just slides right off.
anyway, i wouldn't hesitate to do it again, could probably do in 10 hours next time.
btw, my belt at 118k had zero wear, and the water pump had almost no seepage. I have no doubt this engine could have gone another 50k with no issues.
a. I bagged and labeled all fasteners by major assemblies (water pump, tensioner, covers, etc.). This makes reassembly so much easier.
b. Ordered the TKT021 kit from RockAuto, probably a bit more expensive than elsewhere but no issues with fakes.
c. Most important part of the job is the actual belt removal and reinstallation, and it’s easy to get confused by all the info out there. Here’s what worked for me:
d. Get engine to TDC first, using marks on both cams and crank. The crank will show as 0 degrees. All three will match up. If not, turn crank clockwise until they do.
e. Mark the installed belt and spots on the cams/crank.
f. THEN, turn crank clockwise to 50 degrees mark. Crank will line up with the “pin”, and cams will line up with the “T” marks.
g. Remove the belt by loosening the tensioner. Since you are at 50 degrees there is no pressure on either of the cams to rotate as the belt is removed.
h. Transfer marks from old belt to new belt. Double check this, and again carefully line up all the belt teeth on the two belts.
i. Install new belt, beginning at crank, moving to left cam, then right cam. You really have to pull on that belt to get the marks to match up but they will.
j. Fit the tensioner and gradually tighten those two bolts holding it to the engine block. You’ll feel the belt gradually tighten. Check your 3 marks to make sure they are still line up, then remove the pin holding the tensioner hydraulic compressed. No drama.
k. You’re home free at this point.
l. Strongly suggest use of a torque wrench…many of the fasteners are at 13 ft lbs going into rather soft aluminum. Easy to overtighten and strip things.
m. I did spark plugs, PCV valve, thermostat at same time, drained both sides of engine block of coolant. Might as well.
n. correct tools are really important--i used hose pliers, clamps, usual sockets/ratchets/extensions. My tired 1/2 inch Husky impact got the crank bolt off easily. No need for a puller on the crank dampener, it just slides right off.
anyway, i wouldn't hesitate to do it again, could probably do in 10 hours next time.
btw, my belt at 118k had zero wear, and the water pump had almost no seepage. I have no doubt this engine could have gone another 50k with no issues.
03-29-21, 11:06 AM
#147
Instructor
In step "i", are you using your marks on the new belt and lining them up at the "T" and pin or back at the "I" and zero? This part is a bit confusing. I have a premarked belt. Can't I just rotate to the T and use the factory marks on the belts to line up at the cams' T? And then the CR mark on the belt should be at the dimple on the crank?
03-29-21, 11:41 AM
#148
Great thanks 911LE. All this marking of the belt is confusing, especially the LS430 video where he marks one side at the "I" and the other one at the "T". I just watched a different video for the 4.7 (I know ours is 4.3 but same procedure and parts) where the tech just ripped off the old belt without marking it and used the marks on the new belt. Makes more sense to me.
Last edited by heartygrn; 03-29-21 at 11:44 AM.
03-29-21, 12:25 PM
#149
Instructor
Great thanks 911LE. All this marking of the belt is confusing, especially the LS430 video where he marks one side at the "I" and the other one at the "T". I just watched a different video for the 4.7 (I know ours is 4.3 but same procedure and parts) where the tech just ripped off the old belt without marking it and used the marks on the new belt. Makes more sense to me.
03-30-21, 04:20 AM
#150
It's also confusing that the FSM says to move the crank and cams back to 0 before installing the belt, but it seems like everyone just changes it at 50 degrees. I guess moving back to zero would eliminate the risk of anything having moved while taking off the belt.