SilverES06

I have a 97 ES300 with 146,000 miles, purchased about 2 years ago with 125,000. Does this look like the original timing belt? The woman I bought it from said she had it replaced at 90K, but she didn't have any paperwork, and there is no sticker on the cover. It's in good shape, no cracks/glazing. It says UNITTA, I thought Mitsubishi supplied the Toyota belts.

I'm probably going to replace it before 180K as I have a very slow oil drip coming from the timing belt tensioner area that I think is the rear cam seal...

Oro

It is my understanding both Gates (Unitta in Japan) and Mitsuboshi (not mitsubishi, diff. company) BOTH supply Toyota OE belts. So that could be OE, or dealer-purchased part later.

IME, the cam seals rarely start leaking and it is not SOP to change them on most cars. I believe the advice to do them here is over-cautious. A leak like that is more likely a valve cover gasket. You can try running your hand around the areas of the rear belt you can access and see if any comes up wet and oily.

A few thoughts:

a) I don't know if that's original or a dealer part later so I have no recommendation about that.
b) if you DO change your timing belt, consider these things:
- mark the reference points with a sharpie on your belt before removing it, so you can count teeth and verify the marks on the replacement belt.
- replace the tensioner and all pulleys regardless of what a manual says.
- consider valve cover gaskets and plugs at the same time.

mooseboy84

Cam seals do leak especially if the car is old and its never been changed. I had a bad rear cam seal leak for years I thought was the power steering, but was actually the seal dripping down onto the pump. FYI, the rear cam seal is challenging to get installed. I destroyed 2 seals trying to get that damn thing in given the limited space, then had to order a cam seal installer tool. I got an Aven cam seal installer. Schley makes one for toyota, but the Aven is a knock off for $15 or less and makes the cam install a 3 minute job.

Oro

And this is precisely why I recommend verifying it is leaking before ripping out the old one. They do not often fail (mine are still fine at 255k miles), and for most amateur mechanics a non-leaking seal is a much better bet than ripping it out and putting in a new one and hoping it works out ok.

808mcv20l

I just got through this job this weekend.

Changed the T-Belt on my mom's 99 Camry 1MZ-FE (same as ES300).

to Note, the belt I removed was a Mitsuboshi (I think) was the original belt, car has 84k miles but leaky cam seals forced the replacement.

The T-Belt was in excellent shape, no cracks noticed and no teeth missing. The original drive belts didn't squeak but did have cracks on the undersides, they were also stretched out quite a bit compared to the new ones.

I used the Lisle seal removal tool, put some masking tape over the cam shaft to prevent scratches, seals came out pretty easily using the tool.

I installed the seals using 1.5" PVC piece of pipe and a small hammer (per speedkar9's video). I used the smallest hammer I could find as there's not a lot of space in there and it doesn't require a lot of force to get them in.

I replaced everything with OEM parts, Aisin Timing belt kit, Mitsuboshi T-Belt, Bando Drive belts, KP/Stone Cam and Crank seals, Aisin water pump and gasket, Koyo Pulleys, NTN tensioner, and Kuzeh Thermostat with Stone thermostat gasket. Refilled with Aisin pre-diluted coolant.

The biggest trouble I had was removing the crank bolt, forced me to buy a big honking Impact gun.

When re-installing the rear Cam would move out of TDC due to spring tension and made it hard to get all the timing marks lined up with the new belt. I used a cam holding tool to position the cam while installing the belt.

Also, next time I would recommend removing the power steering hose, from reservoir to pump as it hampered my install quite a bit.

In my experience it's not the timing belt that goes bad, but the other components, leaky cam seals can get oil on the belt and cause it to slip. seized idler pulleys or seized water pump...

There's a reason why they call it preventative maintenance.

mooseboy84

Depending on the severity of the leak I would say its pretty easy to diagnose. I did have a slightly old leaky power steering line, however, looking at the pump and back side of the rear valve cover instantly alerted me to the fact it was more than the pump and coming from a higher source.

I saw the speedkar99 video of him tapping in the new seals, but at least on my 96 es300, it was just to small an area for the pvc pipe and to get solid wacks to drive it in squarely. Thats how I ended up tearing them up by trying to get them straight and they would just go in angled on the backside and then destroying the seal bottom trying to force it in. The Aven seal installer (Aven 058-62232) put it in so easily.

mooseboy84

The first time I ever changed my crank I used the engine crank method to brake the bolt, but when I had to do the cam seals, that didnt work and ended up messing up my socket.
Having a big impact gun can do it, but another way is to use a cheater bar and something to hold the crank. Schley (yes, they make a lot of toyota SST) makes this giant crank bolt tool that fits around the socket that with a 1/2drive breaker bar. You can use that with the tool under the lower control arm, then I used a 20" 1/2drive extension on a jackstand, connected to a breaker bar and a giant piece of pipe to crack the bolt. This is a safer way than the cranking of the engine.

Having the tool to hold the crank pulley in place also makes it alot easier to tighten down the bolt. It sucks because its kind of a $60 1 off tool you dont use frequently, but it makes life easier if you plan to do service on a 1mz engine.

SilverES06

I'm planning on taking the top timing cover off completely this weekend to see what's going on in there. When I first got the car in 2014 I replaced both valve cover gaskets, the leak seems to be coming from somewhere lower. It could be from the power steering pump/hose, I haven't gotten under the car to look.

I'll probably end up doing the belt anyway just because I doubt that the water pump was replaced the first time around (if the belt was ever replaced). I know the picture I posted wasn't great, it was more to show the numbers/markings on the belt.

You'd think if it were original, after almost 20 years and 146K it would show some signs of wear?

808mcv20l

I think it will be hard to see the oil leak even if you remove the upper timing cover.

Timing cover #3 (behind the cam gears) does a pretty good job of deflecting the oil from getting onto the belt.

In my case, everything around the lower timing cover was wet and dirty.

Most people will opt not to change the cam/crank seals because they are such a PITA.

But I can tell you with 84k miles on a '99 those seals were shot, they were hard as a rock and separated into 2 pieces when I took them out.

I replaced my High pressure Powersteering hose, re-sealed the pump and changed all rubber lines. I used ATF fluid in the pump (red) the pump area was still wet with oil I know it wasn't leaking ATF cause it wasn't red and the reservoir was always full. The leak was likely coming from the cam seals.

Yes, and go ahead and change the water pump at 146k on the original pump it's time for it to go.

I also changed out the thermostat but that in itself was another PITA job, I had to remove the Airbox and the bolts to the inlet housing are deep in there with hoses and cables blocking your direct access.

It wasn't a fun job but it was worth saving $1000-1200 at a shop. I also had to make a significant investment in specialty tools:
Crank Holding tool
Crank Puller
Cam Gear Holder
Lisle seal puller
Inch pound Torque wrench
1/2" Ft pound Torque wrench
Impact gun
22mm impact socket

that in addition to the basic mechanics set everyone should own.

808mcv20l

So I took a look again at the T-Belt I took out of the car this past weekend before I dumped it.

It looks exactly like the picture you posted, Toyota with the part# and Unitta on the side, this was from a 99 Camry V6 1MZ-FE.

Also the Waterpump was stamped on the right 98 then an 8, probably denoting an Aug 1998 manufacture, this makes sense as the car is a '99. My New AISIN waterpump I installed was stamped 13 for 2013 most likely I bought it at the end of 2014 (yes I didn't install it till last weekend)

When you have the upper timing cover off take a look at the waterpump to see if it's stamped '96 since your car is a 97, you might need a mirror to see it, not sure if the engine mount bracket obscures it.

speedkar9

Most used timing belts don't show any signs of wear. Rubber breaks down internally and can rupture from within. If you really aren't sure, the best bet is to replace the belt.

A lot of times people can get confused as to which "belt" was replaced. Perhaps the seller thought the timing belt was replaced, when it was only the alternator/ PS belts.

I remember tapping that seal in. It was a real pain and took a good 1 hour out of that timing belt job. Next time I will look into buying a seal installer, especially for the rear cam seal.

LeX2K

I'm always surprised when people say this I've seen many timing belts showing extreme wear, cracks everywhere. As for a seal installer you already have everything needed, use one or both of the old seals against the new one, use the cam gear turned backwards and press in the seal using the cam bolt.

808mcv20l

Hmm that is a great idea, only except my old seals broke apart when taking them out.

The tool looks like it's 14 bucks, I'll invest in the installer tool for when I do the belt on my 2000 ES, My mom's Camry was the practice car lol

My 2000 ES has only 46,900 miles on it but it is almost 16 years old, I want it to go for at least another 16 years!

speedkar9

Genius, I wished I thought of this when doing the TB job!
I'll have to make sure that rear cam doesn't move too much when tightening it back in by holding it with a cam holding tool.

I think my rear seal broke into pieces too, but the front and crank seals came out intact which I could use to press in the new one.

The belt I took off my ES was definitely the original belt at 180,000km. There was a lot of dust under the timing cover but the belt itself seemed pretty intact. The belt on my Solara was roughly 6 years old when I changed it, and the original timing marks were still clearly visible.

SilverES06

Just an update for anyone interested - I ended up tackling the timing belt/water pump job last weekend. The water pump was original, had a date stamp of 11/96. Given the amount of dust and crap inside of the timing cover (and the Toyota stamp on the belt), I'm sure that it was the original timing belt. Pretty impressive that it lasted almost 20 years and 147,000 miles.

My rear cam seal was definitely leaking, so I replaced both cam seals and crank seal. I used the Lisle shaft-type puller, it worked really well. It was a pain getting it in the right position to remove the crank seal. I got the kit from Rock Auto which also had the idler pully and tensioner.

While the coolant was drained, I decided to replace the bypass hose under the lower intake manifold - I was surprised to see that something built a nest under my intake manifold where the bypass hose is. Looks like the nest had been there for awhile, whatever it was must have had a bad day when the engine started...