Add 3x Type 't' Oil Seals To Your Timing Belt Job

[wandawoods]

Hi all,

in the thick of timing belt/water pump job (by my personal mechanic with me watching from his back) for my 97 LS400. we spotted some signs of oil leaks at CAM/Crank shaft. my mech suggested the bad oil seals behind both CAM shafts and crank shaft.

sure enough, after removal of CAM/crank shafts pulleys, the origianl o-ring type seals were indeed in pretty rough shape and engine oil are leaking from the seals. the inner rubber insert have lost all it's elastic and becomes so frail that it can be easily cracked just by pushing it with finger:

the location of the seals are right behind 2x CAM shaft pulleys and the crank shaft pulley down there:

(thanks to lexls.com for the picture)

and you must remove the 3x pulleys (and of course the timing belt) in order to change out the 3 seals.

so the next time when you're ready to do timing belt job, you have better to add them to the list of required parts for TB job. you don't really want to change just these 3 seals alone because you will have to remove the timing belt and the whole 9 yards again....even if the job is to be done by dealer or independent shop, ask the mechanic to change the seals at the same time. the seals are inexpensive but the labor to get there will kill your wallet.

qty2 - lexus part # 90311-38036: seal, type T oil $11.34 (behind CAM pulley)

qty1 - lexus part # 90311-A0001: seal, type T oil $13.62 (behind crank pulley)

[simontaylor]

When these cam pulleys are OFF, are they keyed so that they can ONLY go back on in the correct place, and the same question for the crank pulley?

[blake918]

Simon, you are so awesome!!! That email you sent was just superb!!!!

At 233,000 miles we changed the timing belt on my '95. It's not a complicated task (nothing like that egr pipe), but it is time consuming. I didn't take the cam pulleys off when we did the belt, but the crankshaft pulley is notched allowing it only to go on one way. I'll send a photo so you can see the little groove. We didn't change the cam and crank seals (I'm not sure why) when we did the t-belt and have been kicking ourselves since. A leaky crank seal is brutal; the cooling fan is blowing the oil all the way back to the transmission. Once I start having to add oil between lube jobs, I'll start thinking about changing those seals...I'm hoping it will hold out until 330,000 miles so that I can replace all of the timing belt componetry at the same time.