Cam seals
Correct timing belt, cam gears and back plate must come off. That's why I recommend changing cam and crank seals out when doing timing belt/water pump service. You'll need a cam gear tool to hold cam gear while removing cam gear bolt. Mine was on tighter then the crank bolt. If you need the tool I have one new in box I'll sell cheap. Good luck.
Correct timing belt, cam gears and back plate must come off. That's why I recommend changing cam and crank seals out when doing timing belt/water pump service. You'll need a cam gear tool to hold cam gear while removing cam gear bolt. Mine was on tighter then the crank bolt. If you need the tool I have one new in box I'll sell cheap. Good luck.
Another option is to change the valve cover gaskets too, and use a 32mm wrench on the cam shafts themselves instead of buying the tool.
Here is my list of part numbers from when I did the seals on my 98.
https://www.clublexus.com/forums/per...t-numbers.html
Thread Starter
Driver
Joined: Aug 2014
Posts: 155
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From: Nevada
Thanks guys for the help. I bought the car a couple years ago. The previous owner had paperwork that the timing belt was changed. I'm willing to bet whoever changed the belt didn't change the cam seals. I plan on doing the timing belt job myself in the near future. Will only be my second time doing a timing belt but I think I'll be fine. I had an '01 Nissan Xterra and I did the timing belt on that suv. Looking at videos and how to's I think the Sc timing belt is much more steps but I think if I take my time it'll be fine.
It's not too bad of a job on the SC300 since the belt is right in the front. Once the radiator is out of the way there is plenty of space. Are you sure that its the cam seal leaking and not the vvt-i cam?
For specialty tools:
- You'll need to have a large C clamp or hydraulic press ready to reset the timing belt hydraulic tensioner. The tensioner is a grenade pin style (you reset, put a pin in, install, then pull the pin when you're ready.)
- Timing gear puller to get the harmonic balancer off (if its stuck)
- Harmonic balancer holder (to keep the harmonic balancer from rotating when you break torque and torque to spec)
For specialty tools:
- You'll need to have a large C clamp or hydraulic press ready to reset the timing belt hydraulic tensioner. The tensioner is a grenade pin style (you reset, put a pin in, install, then pull the pin when you're ready.)
- Timing gear puller to get the harmonic balancer off (if its stuck)
- Harmonic balancer holder (to keep the harmonic balancer from rotating when you break torque and torque to spec)
Thread Starter
Driver
Joined: Aug 2014
Posts: 155
Likes: 0
From: Nevada
It's not too bad of a job on the SC300 since the belt is right in the front. Once the radiator is out of the way there is plenty of space. Are you sure that its the cam seal leaking and not the vvt-i cam?
For specialty tools:
- You'll need to have a large C clamp or hydraulic press ready to reset the timing belt hydraulic tensioner. The tensioner is a grenade pin style (you reset, put a pin in, install, then pull the pin when you're ready.)
- Timing gear puller to get the harmonic balancer off (if its stuck)
- Harmonic balancer holder (to keep the harmonic balancer from rotating when you break torque and torque to spec)
For specialty tools:
- You'll need to have a large C clamp or hydraulic press ready to reset the timing belt hydraulic tensioner. The tensioner is a grenade pin style (you reset, put a pin in, install, then pull the pin when you're ready.)
- Timing gear puller to get the harmonic balancer off (if its stuck)
- Harmonic balancer holder (to keep the harmonic balancer from rotating when you break torque and torque to spec)
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There are vvt-i gear rebuilds are available through Jeff Tsai/Power Dynamix. He sells the seals by themselves, offers rebuild service, or sells gears that are already rebuilt.
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Thread Starter
Driver
Joined: Aug 2014
Posts: 155
Likes: 0
From: Nevada
It's more likely that the vvt-i gear is leaking oil (it's the same general area). It's a common leak on the 98-00 SC300. Unfortunately, its more expensive to replace. The entire gear is supposed to be replaced if you go OEM. The cam seals should also be changed since its only a few steps more.
There are vvt-i gear rebuilds are available through Jeff Tsai/Power Dynamix. He sells the seals by themselves, offers rebuild service, or sells gears that are already rebuilt.
There are vvt-i gear rebuilds are available through Jeff Tsai/Power Dynamix. He sells the seals by themselves, offers rebuild service, or sells gears that are already rebuilt.
If I take the car to a shop or have a pro do the timing belt and replace all the seals will they be able to diagnose the vvt-i gear leak if they see it? I might just have someone else do it since I'm lazy and don't want to waste my weekend on it. I have seen videos on youtube where they replaced just the seal on the vvt-i. Just not sure what route to go. Just tired of the oil leaks lol
They should be able to diagnose it. If the leak is large enough, then you'll see it right away when you take off the timing belt cover. It's 6 5mm hex bolts holding the plastic cover on. If you see oil sitting on the lip of the vvt-i gear, then the gear is leaking oil.
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