Help me with how to replace a head gasket and starter
Replacing a head gasket is not a DIY job, unless the person has plenty
of experience, knowledge, and the proper tools. The fact that a person
would even ask, "How to replace a head gasket", would indicate to some
that they should not trying to do that repair.
To replace a head gasket you must remove the intake manifold,
exhaust manifold, valve train, and then the head. This is very involved
and requires disconnecting lots of sensors and the ignition system. The
head must then be checked to see if it is warped, or cracked, and
repaired if necessary. You must then know how to put all this back
together and torque all the bolts in the proper sequence. This takes
training and skill which the average shade tree mechanic does not have.
There is a difference between say a over head cam (OHC) engine
and a internal cam engine. And then if it is a V6 or V8 then both head
gaskets must be replaced even if only one blew. And last but not least,
you have to find out if there is other engine damage and what caused it
to blow the gasket in the first place. Definitely not for an amateur.
The best answer to this question: Take it to a professional.
The second-best answer: Get a repair manual and follow
directions. A repair manual does not provide the training necessary to
do this repair correctly, and not near enough information, but it can
provide more info than can be written out in an answer like this.
Below is the best answer we can provide in this format.
* Make sure you have a torque wrench and the correct torque specs for your vehicle
Exhaust flange nuts and bolts
Head Gasket (preferably OEM)
Ten head bolts
Two valve cover end seals
Tube of RTV silicone
1. Disconnect the battery negative terminal
2. Drain the cooling system
3. Raise the front of the vehicle and support it with jack stands .
4. Remove the two 13mm exhaust bolts holding the exhaust pipe to the exhaust manifold, lower the vehicle
5. Remove the air cleaner assembly
6. Remove the upper radiator hose
7. Loosen the 13mm nut holding the dipstick tube bracket to the
thermostat housing and remove the coil (if it is attached to the
thermostat housing) and unplug the coolant temperature sensor
8. Remove the spark plug wires from the plugs, remove the
distributor water shield and the distributor cap (this step is so you
don't damage the distributor cap).
9. Remove the two uppermost 15mm-head bolts from the top of the
a/c , alternator bracket where it attaches to the head and unplug the
single wire temperature sending unit
10. Remove the upper half of the timing belt cover
11. Remove the valve cover
12. Disconnect the wiring harness connector that is just to the right of the throttle body
13. Disconnect the throttle cables from the throttle body and remove the two 10mm head bolts holding the bracket
14. Disconnect the vacuum lines from the throttle body
15. Disconnect the fuel lines - NOTE : The fuel lines may be under pressure , use extreme care when removing them
16. Disconnect the throttle position sensor connector and the EGR valve connector (if equipped)
17. Carefully lift up the throttle body wiring harness , the
fuel lines , and the vacuum lines together and use a bungee cord to
hold them out of the way
18. Remove the ground strap that is attached to the intake manifold from the fire wall
19. Remove the 15mm-head bolt holding the battery ground cable to the engine
20. Disconnect the vacuum hose from the power brake booster and the heater hose from the intake manifold left side
21. Use two plastic tie straps to secure the timing belt to the
camshaft pulley and remove the pulley . Hold upward tension on the
pulley and secure it with a bungee cord to the right hood hinge - NOTE:
be sure to hold the upward tension with the bungee cord so the timing
belt doesn't jump a tooth on the lower pulleys
22. Remove the head bolts and lift the head off the engine
block . (I suggest having an assistant help to lift off the head) With
the head removed , carefully check the head casting for signs of
cracks. Also use a straight edge to check the head casting for warpage
(maximum allowable warpage is .00
23. Clean all the head gasket mating surfaces and wipe clean
with a little brake cleaner on a rag. Use a round plastic bristled
brush to clean out the head bolt holes in the engine block and blow
them out with compressed air .
1. After the gasket surfaces are prepared, set the new head
gasket in place and CAREFULLY place the head into position, take
extreme care not to place the head on the head gasket until it is in
the proper position.
2. With the head in place, install the head bolts. You will
need to tighten the head bolts in a circular pattern starting from the
center and working your way out. I recommend hand tightening all the
bolts before beginning the torque sequence. Head bolt torque: For older
style 10mm head bolts : 35 - 45 - 45 - and a 1/4 turn; For newer style
11mm head bolts : 45 - 65 - 65 - and a 1/4 turn
3. Use the two rubber valve cover end seals and a bead of RTV silicone to reseal the valve cover.
4. Do Not let the silicone skin-over before setting the valve
cover into place and tightening the bolts, also be sure that both
mating surfaces of the valve cover are clean and oil free .
5. After the head is reassembled you will need to reset the
base timing to specs. You will also want to double check the timing
belt position . Use a variable timing light and set the timing mark on
zero degrees . Save the setting on the timing light and shine it
through the inspection hole in the top of the upper timing belt cover .
If the belt timing is correct , you will see the oblong hole in the
camshaft sprocket centered in the inspection hole .
Hope my info solves your problem,
Thanx for using fixya......
Oct 02, 2008 |
1998 Saturn SL