Performance & Maintenance Engine, forced induction, intakes, exhausts, torque converters, transmissions, etc.

HELP on replacing the headgasket

Thread Tools
 
Search this Thread
 
Old 06-24-09, 07:16 PM
  #1  
iduntnoega
Driver
Thread Starter
iTrader: (4)
 
iduntnoega's Avatar
 
Join Date: Jun 2009
Location: CA
Posts: 109
Likes: 0
Received 0 Likes on 0 Posts
Default HELP on replacing the headgasket

hey guys, can you guys give me steps or any tips on how to replace a headgasket. I'm trying to take off the timming belt but not sure on what to do from there. Is there a tensioner or something?
thanks
Old 06-24-09, 07:46 PM
  #2  
slappy96
Lead Lap
 
slappy96's Avatar
 
Join Date: Oct 2006
Location: Nebraska
Posts: 468
Likes: 0
Received 1 Like on 1 Post
Default

Sc300? or 400? for starters.

Yes, there is a tensioner pulley and it takes a 10mm Allen wrench. Tensioner itself is lower left of the pulley. Thread in my sig has pictures.

There is also quite a bit more that you can find in the factory manual and searching.
Old 06-24-09, 08:07 PM
  #3  
lemmiewink
Lead Lap
 
lemmiewink's Avatar
 
Join Date: Oct 2006
Location: texas
Posts: 581
Likes: 0
Received 0 Likes on 0 Posts
Default

If you are planning to do the headgasket without the manual, I would stop and rethink this. It will tell you pretty much all you need to know. From the torque values of your head bolts , to your cam bolts. Also they show in which order you should torque them. Especially the cams. If you do not torque the cams down as per manual, you will risk damaging components.

I would change the waterpump also if it has not been changed, since and easy to do at this point.
Replace some seals that you shouldn't reuse, such as your cam seals. Valve cover gaskets.

It is also a good opportunity to change your timing belt, but this (along with replacing the water pump) requires removing your crank pulley.

Either way you have your work cut out for you.

Good luck.
Old 06-24-09, 08:22 PM
  #4  
al4nek
Driver
 
al4nek's Avatar
 
Join Date: Apr 2007
Location: IL
Posts: 184
Likes: 0
Received 0 Likes on 0 Posts
Default

question about water pump....when i tried to order one for my car (95 sc300) i found out there is two different, 10 and 11 fastener design. How do i check which one i got before removing anything?
Old 06-24-09, 10:27 PM
  #5  
iduntnoega
Driver
Thread Starter
iTrader: (4)
 
iduntnoega's Avatar
 
Join Date: Jun 2009
Location: CA
Posts: 109
Likes: 0
Received 0 Likes on 0 Posts
Default

the car is a sc300
Old 06-25-09, 04:30 AM
  #6  
mteele
Lexus Champion

iTrader: (5)
 
mteele's Avatar
 
Join Date: Jul 2004
Location: North Carolina
Posts: 2,113
Received 3 Likes on 3 Posts
Default

Get a factory repair manual, only way to do this job yourself. The head has to be torques back down in a certain order, the cam caps have to be reinstalled in a certain order, then loosened and reinstalled in a certain order while rotating the camshafts 120 degrees...Its pretty exact.

How far into tearing apart the motor are you? Its a very challenging job, especially with the intake manifold design. I just completed my headgasket and it took me 10 days from start to finish. (2 weekends and working every night on it during the week). You'll want to replace your timing belt, front crank oil seal, water pump (depending on your mileage), camshaft seals, valve cover gaskets, timing belt cover gaskets, fuel injector o-rings....

Its also a good time to do a few mods. I deleted my EGR system, removed the vacuum tank under the intake manifold, the charcoal canister, and a bunch of other misc. vacuum tubing and switching valves.
Old 06-30-09, 01:06 PM
  #7  
gdc5ind
Pole Position
 
gdc5ind's Avatar
 
Join Date: Jul 2007
Location: CA
Posts: 247
Likes: 0
Received 0 Likes on 0 Posts
Default

WOW

Sometimes when you blow a head gasket you damage your head....Its never good to replace the head gasket without having the block and head decks checked. If the decks aren't right your new head gasket will leak. Like i said before there might be damage to the head, but most of the time the damage is to small for the naked eye.
Old 06-30-09, 03:15 PM
  #8  
Enigma8246
Lead Lap
 
Enigma8246's Avatar
 
Join Date: Sep 2007
Location: 501
Posts: 481
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by al4nek
question about water pump....when i tried to order one for my car (95 sc300) i found out there is two different, 10 and 11 fastener design. How do i check which one i got before removing anything?
The best way is to call the dealership and give them your VIN. They told me the wrong one. I didn't realize it until I had the front of my engine taken apart. My car is a daily driver and i couldn't wait for another so i wasn't able to do my water pump.
Old 07-05-09, 12:16 AM
  #9  
gdc5ind
Pole Position
 
gdc5ind's Avatar
 
Join Date: Jul 2007
Location: CA
Posts: 247
Likes: 0
Received 0 Likes on 0 Posts
Default

There are some useful links in this thread.
https://www.clublexus.com/forums/per...ml#post4652680
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Htle83
GS - 3rd Gen (2006-2011)
3
11-13-23 02:58 PM
Lexinky
LS - 1st and 2nd Gen (1990-2000)
14
09-05-12 05:23 PM
OG Dada
Performance & Maintenance
2
07-27-12 07:49 PM
rcgo88
Performance & Maintenance
7
06-12-12 10:56 PM
sahtt
Maintenance
3
02-27-06 09:19 AM



Quick Reply: HELP on replacing the headgasket



All times are GMT -7. The time now is 08:56 PM.