I been having problems with this GS300 since I bought it. It has over 260K miles but it runs fairly good, had a nasty oil leak and needed a little TLC. I decided to do some work to it, we changed out the timing belt, waterpump along with both Camshaft seals and Crank seal. I messed up installing the timing belt, instead of setting the marks the 60*TDC, I had it on TDC and moved the intake cam which lead to 4 bent valves(2 valves on cyl 1 & 2 valves on 6 cyl). I had trouble removing the head, I had stripped two bolts on the intake manifold that I couldn't break loose so I decided to pull the motor out along with the trans, I pulled the motor out of my SC300 with a 5spd trans out several times so I knew what I was getting myself into but I never pulled a motor with an automatic transmission before, I disassembled a few things that were unnecessary.


I got the head back from the machine shop, installed everything back into the car, guess what, the car will not start . Not only Im having problems starting the car, I have an oil leak and I am clueless what it can be. I'd like to fix the oil leak before anything, cause whenever I crank the car for a few seconds there is a good amount of oil coming out of the center of the VVT-I cam gear. When I installed the cams back onto the head, I noticed there was a pretty good gap around the cam itself and the cam seal, isn't the cam seal suppose to sit tight around the CAM like the exhaust side? Is the intake cam seal different from the exhaust cam seal? I bought factory seals from Concord Lexus, both cam seals where identical, im not sure if they are suppose to be.


I must have removed, installed the TB 3 times by now and Im a little frustrated with this oil leak. I read that the VVT-I cam gear is the culprit to these oil leaks. So I contacted Jeff Tsai, bought 2 of his Viton Seal kits, installed that with the new 0-ring seal but the leak still present. I was sure that it was the VVti cam gear so I bought a good used one from Aliga, installed that unit and it still leaking.

Im going to pull the TB off again to take pics of the cam seal around the cam when I get the chance, but Id like to ask Im I missing something between the cam seal and the bolt inside the vvti bolt? This is where the oil is protruding from. and are the both cam seals the same or are they different sizes?

 

I recently did a tb job on my gs300. Yes I do believe both cam seals were the same. Also if I remember correctly, the seals should sit flush in their enclosures.
I would think you possibly installed one of them incorrectly, or maybe did you forget to use a sealer on the little metal piece that holds the cam seal? You would only need to use the sealer if you actually took the metal piece apart to remove the old seal. If you just yanked out the old seal with a hook then you would not have needed to use any sealer at all.

Just trying to give you some ideas.

 

Forgive me if this comes across sounding wrong - but with the abundance of cheap used motors that are good, why would you try to repair a high milage motor? You probably spent the same or more than it would cost to just get a motor with no issues. Swapping a motor is one thing, taking the motor apart and reassembling it is another.

 

Oh shoot! I just realized I RESPONDED TO YOU, in a different thread!!!! LOLOL

What was meant for you:

Hey brother, so check it out, its obviously not the vvti cam pulley, that you've figured out. Your cam seals aren't seated properly 100%. Let me ask you this, did you remove the cam seal caps? Assuming you obviously replaced the valve cover gaskets to right? Answer that one question regarding the caps and we'll go from there. How's the crank seal? Did that one seat properly? Guess you won't know until you get the cam seals dry actually huh. Anyhow I have very detailed video's of the entire process and how I actually do the job as I've done it many times with perfect seals everytime so far, (knock on wood) both Is's and our Gs's, same thing obviously but yea... Let us know.