Baker Bootleg

Okay i have a 91LS, and i took out the radiator and the drive belt. Now how do i go about removing the timing belt and replacing it? Anyone done this before or is that any guides on the net? thx

VVT-i

Baker..that's a lot of works man. You have to remove all the engine covers just like when you change your spark plups. Then the L and R timing cover, the thermostat housing, the A/C compressor, the Alternator, the fan, the fan pulley...etc..You name it. I rather go to Lexus dealer and pay a little bit more for them to do all these.
I see a lot of problems after somebody replacing the timing belt and they put the Cam Sensor's wire in the wrong spot. Then the wires are rubbing with the drive belt and cut it. So, you got a check engine light..

Baker Bootleg

have you done this yourself? i'm just wondering

Pilot

Changing the timing belt is not for the back yard mechanic. I watched while mine was done, and I was shocked at how far the engine comes apart. There is also a special way to release the spring tension on the belt, that is not easy to figure out, without expericence or a manual.
I changed all front engine seals at the same time, for only a few bucks extra. They were all exposed, and only took a few minutes to replace. (Both cam seals, and the crankshaft)

Pilot

91 LS400

LexJunkie

I changed mine about 5-6 years ago, so my memory of the experience is a little hazy. I remember being very impressed with how easily everything went back together.
The biggest problem I had was taking off the crank pully. Went thought several rented impact guns and compressors (not strong enough), finally a neigbour came over and held the flywheel with a big screw driver while I broke the bolt loose with a breaker bar.

As far as the tensioner goes, I compressed the plunger into the housing and stuck a small alen (sp?) wrench through the hole in the housing and the plunger to keep it compressed. Pulled out the alen wrench when the new timming belt was installed, and it expanded.

Did not have to completely remove the A/C compressor or the alternator, removed the front bolts, loosened the back ones, and pushed the units out of the way.

All that being said, I also don't recommend doing this unless you've got some automotive experience.

I know that the '90 LS400s had a weak water pump (prone to leaking) and I suspect that the '91s had the same problem (if I remember correctly the problem was fixed in '92), so if your waterpump has not be replaced before, this would be a good time to replace it.

Hope this helps,
Darek

Baker Bootleg

i got everything off the front, except i cant get that pully off. When i try to turn it, it just turns the timing belt to.

Supra94Red

you probably need something like this to hold the pulley
in place while you bust the crankshaft bolt loose

http://store.yahoo.com/autotoolexpress/chainwrench.html

just make sure you wrap the pulley with an old belt or some
peice of rubber to prevent the chain from damaging the pulley.
also rest the chain wrench on the waterpump or something
nearby since you won't be holding onto it.

LVgs400

If you put that belt 1 tooth off of the check points, it could cause huge damage to your engine at start up. I would have a tech finish putting the timing belt on for you, and just put the rest of it together from there.

hyperopt

Why pay a pro to put on a timing belt when it is much easier to put on the belt correctly than it is to remove the crankpulley?

Putting on the timing belt one tooth off on a non-interference engine won't hurt the engine except to change the timing which results in rough running engine if it runs at all. Make sure to turn the crankshaft by hands (eg. via rachet) at least two revolutions after puting on a new belt to check for bindings, belt meshing, and any abnormalities.

goldz

Hi,

Say, does anyone know if the crankshaft bolt on a '99 SC 400 is normal right-hand thread, or left hand?

Thanks,
goldz

buttons

tutorial:
http://www.lextreme.com/timing.htm

hotmachine

If you want to do it yourself make sure you have the right tools and a manual. I've changed a belt on a 2JZ but never on a 1UZ though.

Do you live in Socal? If so, PM me. I know a place that would do a much better job and better pricing than a dealer.

goldz

Thanks for the replies. I called a couple of Lexus shops (and got a couple of different answers) but eventually got the info I needed. The belt is in, along with a new water pump and timing belt idler pulleys. I did come up with a nifty tool to keep the crankshaft pulley from turning, and would be happy to share the info. I don't check my messages often, though. Oh, I put in a starter, too. Talk about a headache, but with a little patience (and some wrenches that have been heated and bent) you can remove the bolts that hold the starter in, from on top, rather than using a long extension underneath the car.

Thanks again,
goldz

gserep1

They are standard right hand threads. On my 99 GS4, the bolt head is a 22mm. I used a LONG 1/2 inch drive breaker bar and a 22 mm socket. I removed the E1 fuse to prevent starting, placed the bar on the ground on the driver's side of the engine, and BUMPED the starter, and the bolt broke free. That is easier that trying to hold the flywheel or something.

I changed m belt last week. it took 3 tries to get the belt just right, bu there was NO way I was going to start the engine unless the timing was right, I changed the bearings, tensioner, water pump, thermostat at the same time as the belt.

Runs sweet!

GSEREP1

saber

gserep1, near the end of your timing belt job, how did you keep the engine from turning when you went to tighten the crankshaft pulley bolt?