harryliu

When changing timing belt for 2001 GS 300, do I need to change the water pump, timing belt tensioner, timing belt pulley, thermostate, crakshaft seal, cramshaft seal in the same time? The onwer's manual suggested to changing timing belt at 90,000 miles, but does not mention to change any of the above. You advise is greatly appreciated.

gserep1

Those items are recommended to be changed because if they were to go bad after replacing the timing belt, one would have to go back in again to fix it . If the antifreeze were changed on a regular basis, I am sure the water pump and thermostat would last longer, but HOW much longer has not been determined. It is better to be safe than to be sorry. I DO wonder how much longer these parts CAN last, but no one I know is willing to go all out and test it. I know I won't be the first to try it.

The factory service manual does not say anything about replacing the crankshaft and camshaft seals, but they DO talk about removing the pulleys themselves to inspect them. When I do my own timing belt next week, I will be able to tell if my seals are leaking, and I will only remove the pulleys if the seals need to be replaced or the teeth look worn.

GSEREP1

JPI Racing

When you are doing t-belt, I would suggest that you replace cam seals, water pump and o-rings with it. These are VTT-i motor so You could bend the valves if you don't do it right. I would set the timing at 10 degree. Good luck.
JPI-

disc108

i will be changing my timing belt over christmas and want to verify a few things:

1) i will be ordering a thermostat, water pump, upper and lower radiator hoses, the 3 o-rings for the water bypass outlet, and the gasket and o-ring for the water pump.

also replacing timing belt tensioner and idler pulley. what is the "timing belt pulley" mentioned above?

should i replace the crankshaft seal and camshaft seal and if so, where are these pieces located? I can't find them labeled as such on my repair manual.


2) in my repair manual, page EM-17, step 10. it says to "always turn crankshaft clockwise." but then it says to turn the crankshaft pulley 60 degrees COUNTERCLOCKWISE to place the sub timing mark (60 degree mark BTDC) on the crankshaft pulley at the timing mark "0" position.

i am confused on how to align the cams and crankshaft pulley. i should align the cams TDC on the timing marks but how should i align the crankshft pulley? should i turn it clockwise or counterclockwise?

3) are there any other things i'm forgetting or is there any helpful advice?


Thanks in advance,

Ted

melarainc

It is recomended to do the water pump and seals at the same time and also you will be saving some cash if it is beeing done by a shop.
I have asked the dealer and a independet shop and the answer was the same if you want peace of mind this would be the way to go.

JPI Racing

Ted,
This job is not for DIY. Take my advise and have a qualify Lexus Tech do this job. So you don't have to spend $4000 for a new head and valves.
JPI

disc108

No worries. My very experienced uncle will be helping me and I just want to confirm that I will be ordering the right parts.

JPI Racing

Good luck
JPI