Sunday 5 June 2011

How to change a head gasket on a 1994 chevy k1500 ?

If possible, I need step by step instructions on how to change a head gasket on my husband%26#039;s truck. Please, if your advice is %26quot;take it to a mechanic%26quot; or %26quot;buy a manual,%26quot; don%26#039;t answer.|||Thorough step-by-step procedures with pictures can be found here;


http://www.autozone.com/az/cds/en_us/090鈥?/a>


Click on pictures to enlarge, and links in box to right for procedures on Intake Manifold and such.|||Actually a manual will help a lot, but anyway (assuming this is a 350 5.7 tbi) you need to remove the intake manifold, to do this remove the throttle body unit then the distributor (remember to mark it for timing) then undo all the bolts on the manifold and remove. Then take off the valve cover, then loosen all the rocker arms once those are loose remove the head bolts then pop off the head. When you put it back together the timing on that side of the engine will be off and you will need to adjust the rocker arm bolts with it running, do that once you put the intake and tbi unit back on and everything else all back together. Thats about all i can think of but go to autozone or somthing and get a good repair manual it will have step by step instructions and all the torque specs..|||1. Drain the coolant


2. Remove the air filter ducting


3. Disconnect all vacuum/fuel hoses %26amp; mark them with masking tape


4. Heat the bolts that hold the header pipe to the exhaust manifold %26amp; remove


5. Remove the exhaust manifold from the head


6. Remove the valve covers


7. Loosen all rocker arms


8. Drill (8) 鈪?quot; holes in a piece of 2X4. Mark then 1-4 I/E [intake/ exhaust] so you do not mix up the push rods once they are removed.


9. Remove the push rods %26amp; place them in the corresponding holes in the 2X4


10. Remove the distributor cap %26amp; wires. Turn engine to TDC; rotor facing #1 spark plug lead


11. Remove the distributor


12. Remove all accessories from the front of the engine such as A/C Alternator, ect


13. Remove all the bolts from the intake manifold %26amp; remove


14. Remove the bolts from the corresponding head


15. Remove the head





禄禄禄|||Put the k1500 into a place where you have good light and a good place to work. Don%26#039;t try to do it out here it can get rained on etc.


Look at the engine. Notice there is a lot of stuff in the way of taking the heads off.


Drain the cooling system, and save the coolant in bottles so you can pour it back into the engine


Disconnect the battery and hook it up to a %26quot;float%26quot; charger.


Start at the left rear of the top of the engine and remove and disconnect everything that is in the way of the heads.


Mark everything you take off with a sharpie (permenant balck majic marker) as you take them apart so you can get them back together right. I use adhesive lable tags masking tape is also ok. the long narrow white ones work good. Also get some zip seal sandwich bags and put the nuts and bolts for each thing that comes off in a nice neat bag and label it as to what it was for.


Work your way around the engine to the right.


When everything is our of the way and disconnected take off the valve covers.


Manually crank the engine around until it is at TDC on #1 Cylinder on the firing phnase. This will allow getting the distributor back in the fight place. Mark where the distributor rotor is and remove the distributor. It should be pointing to the #1 plug wire. Take all the plug wires off the plugs and keep the wires all together with the cap.


Next the intake manifold comes off bag the bolts and lable them what they were from.


Cover the area where the intake manifold was with clean cloths to protect the engine from getting any foreign material down there.


Remove the pushrods (label each one so you can put them back exactly where you took them out so you can get them back exactly where each one was. An old cardboard box with holes punched in the flaps makes a good/cheap way to keep them in order (the how is up to you). The cardboard box can also be used to keep the bolt bags and parts together.


Disconnect the exhaust manifold from the exhaust pipes. The nuts will likely be very tight and may strip if you don%26#039;t use penetrating oil or heat to break the rust.


Back off each of the cap screws that hold the heads on one turn and then crank over the engine with the starter (you must reconnect the battery to do this and disconnect it after you do this step.). This should pop the heads loose from the block so you won%26#039;t have to pry it/them off.


Finish taking the head cap screws off and remove the heads


Take the heads to a machine shop to pressure test them for cracks and for flatness of surface. I would recommend having them do a valve job on the heads while they have them if you can afford it.


Clean the surface of the block where the head seals of all crud and old gasket material. Acquire a new gasket set called a %26quot;head set%26quot; for your engine by VIN of the truck if it is the stock engine if it is not the stock engine id the engine


Always use the best grade gasket set like the Fel Pro to reinstall. Get the head gasket type which is laminated.


Put everything back on the engine in the reverse order you took it off. Putting the heads back on requires the surfaces to be completely clean of all dirt and crud.


Vacuum all the dirt and crud that may have gotten into the pistons.


You will have to get the manual to get the torque specifications for the proper torque setting for all the bolts that hold everything together. You can probaably check one out of your local library to keep the costs down. The pattern and torque of the bolts is crucial.


Get a good quality torque wrench (Craftsman for example) to set these it%26#039;s the only way it can be done right. And with this stuff it is either do it right or don%26#039;t do it.


Once your have the heads on and torqued up you can put the push rods back into the engine. Make sure they are in the little sockets in the top of the lifters-make sure you get each one back where it came out. They each have a wear in pattern that is matched to where ther were. If you put them in the wrong spots there may be premature failure of the push rod or rocker arms.


Take the cloth out of the valley area below where the intake manifold goes, and make sure no dirt has gotten in there. If any has it must be removed. A Vacuum wand works good or a magnet for nuts and bolts.


Put on the intake manifold and make sure the little end gaskets are in the proper place or the engine will leak oil there.


Torque up the intake gasket with the proper torque and pattern by the manual.


Manually turn the engine back to TDC on the #1 cylinder at firing phase. Reinstall the distributor.


reconnect the exhaust manifolds to the exhaust pipes. Use new nuts and hightemperature anti seize compound and it will be easier next time to take them off.


reconnect all the stuff you disconnected around the engine from your tags and the bagged bolts from right to left.in an orderly manner to no miss anything making sure you get it all back together by the numbers or letters.


When everything is back together put the coolant back into the engine and check for leaks.


Reconnect the battery to the cables,


Check the oil level


Spray a very small burst of starting fulid into the air intake of the engine.


Start the engine; It should start just fine.


Do a normal lube change within the first 100 miles after you finish to get ride of any crud that fell into the engine..


Good luck|||you will need the manual if for nothing else for the toque sequence of the head bolts and what to torque them down at the same with the intake and exhaust manifolds|||if you are that stuburn, that is fine but allot of useful information is found in that book like the torque specification and order along with all of the little steps to get the job done correctly the first time. i haver been working on cars for 25 years and i believe that the book should be looked at like the mechanics bible.

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