When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Any help is very much appreciated. Started with what I thought was a crank seal leak, and ended up being cam seals as well. Luckily I bought a timing belt kit which included all three seals. Followed timing belt replacement instruction and started disassembly. Replaced seals and installed new timing belt. Both cam plate grooves matched "I" and crank sprocket groove matched with dot on casing. When I start the car I get rough idle and random misfire code. Checked connections and hoses for any chance of vacuum leak, all checked out good. I decided to take cover back apart just to verify my timing. Once again I line up crank mark and verify that grooves on cam gears are matching as well, checked out good. I rotated crank 360 and timing marks line up on point without belt timing marks lined up, rotate 360 one more time and marks line up on point again with belt marks matching too. Put front end back together again with same outcome, I have to keep foot on gas to keep it running. I did notice after a while cat would start glowing so I shut it off. No noise from engine like knocking or ticking. Not sure on the the next step to take.
Just to add, I did notice the coils are really easy to slip on and slip off the plugs. I just don't see all coils going bad especially when it ran fine before I started oil leak repair. On the other hand I just bought this car and it has over 270k miles.
No problem man. The guy I bought it from had an issue when installing a new timing belt and managed to crack the right side intake camshaft. He found a replacement camshaft at a junk yard, but it was out of a 2000 LS400. He assumed that since the 1z and 3z are nearly identical that the camshaft would work. I re did the timing belt when I bought it just to make sure everything was in time and it was. I called lexus to see if the part numbers for the 2000 ls400 and 2002 gs430 were the same for the camshaft, and sure enough it was not. The problem now is sourcing the correct cam as the dealership is only showing one, but he is trying to make sure that dealer actually has it on the shelf. The newest lexus year at my local junk yards are 2000 and there not the 4.3L.
I stand corrected, Lexus parts guy called back and wanted to verify my vin. According to him the camshaft is the same, part number 13511. Not sure what could be wrong that's causing this.
To replace the cam seals on your motor, the cams need to be removed with a service bolt on the scissors gears of each bank.
Bank 2 is easy, service bolt hole is in the 12 o'clock position, bank 1 service hole is in the 6 o'clock position requiring a 180* rotation of the cams in bank 1 (without the Tbelt on).
There are factory dots to line up before removal and on the reinstall.
All this needs to be done at 50* ATDC cam marks will line up with the “T”.
There is no shortcut to this procedure, sounds like the T belt is on correctly but the cams are off.
First pic shows the service bolt on bank 2 before removal.
Second pic is the timing tube separated from the cam to install the cam seal.
Thanks for the response Frank. When I did the seals I never removed the exhaust side camshaft, I "rolled" out intake cam, disassembled to install new seal, then "rolled" intake cam back in. I did this for both sides and also at top dead center, not 50 degrees after. With me start back from scratch, what do I need to verify when looking at cams? If the scissor gears happened to spin by chance, would it cause the symptoms I am having?
...yes if the scissor did not have a service bolt in place when intake cam was removed the cam timing will be off.
You will need to reclock the scissor gear on the exhaust side.
I have never needed to do this but I assume the exhaust cam needs to be removed and the scissor gear needs to be realigned some how...
To reset the preload on a scissor gear secure the camshaft in a vice on a section that will not damage the lobes or journals. You will need to rotate the scissor gear against spring pressure until the service bolthole lines up with the thread. Normally a large pair of pliers or multi grips will be sufficient to do this. Holding the gear in place with one hand fit the service bolt all the way through the gear. The bolt only needs to hold the preloaded gear in place and does not need to be any more than finger tight.
Got it. This time I will do it at 50 degrees after like you stated. Do you remember size service bolt was? Thanks for you help, I really appreciate it.
10-21-19, 06:32 PM
2002 GS430 Timing Belt Issues
