The original KA24DE engine is based on a composite head gasket that mades from composite components. These are great at wrapping up imperfections on the engine head and block surfaces. However, the composite component often degrades with time, eventually leading to a broken head gasket. When properly constructed, the KA24DE engine head gasket is able of containing higher cylinder pressures within boosted condition.
There are also MLS (Multi Layer Steel) option for KA24DE engine head. The MLS version head gasket was made from stamped or laser-cut sheets of steel thinly layered in Nitrile component. The MLS gaskets tend not to weaken like their OEM composite version.
The only problem with MLS head gasket usually the surface finish on both the cylinder head and block needs to be fixed and consistent to work properly. Surface imperfections often leads to cooling system leaks or combustion chamber gasses getting out under pressure.
How to Change Head Gasket on ka24de engine?
So, you want to rebuilt your Nissan KA24DE engine. Here are the step-by-step to change KA24DE engine head:
First of all, drain coolant from the engine. Remove spark plugs then turn the motor over so that #1 piston is at TDC on the compression stroke. Make sure the crank pulley ‘0’ mark lines up with the pointer. Remove valve cover. Make note of timing marks on sprocket and chain. What ever you do, make sure the engine is NOT turned from this point on or your cam timing can get screwed up.
At this point you need to install a wedge down between the two sides of the chain so that the chain doesn’t drop down and disengage from the bottom crank sprocket or it will lose it’s timing position. The wedge should have a wire attached to it which will hang over the edge of the timing cover so that it can be pulled easily; you can use nylon ties instead to hold each side of the chain up. Remove cam sprocket.
Disconnect intake manifold at KA24DE engine head. Disconnect exhaust manifold at engine head. Disconnect all remaining electrical connectors/wires going to head and mark them. Disconnect all vacuum lines attached to head and mark them.
Remove head bolts in the correct order as follows:
2 8 10 5 3 <== front of motor 4 6 9 7 1
Head bolts should be loosened in two to three steps.
While you have the head off, this would be a good time to regrind the valves/seats and to install new valve stem seals if you’ve got a lot of miles on car. Check engine head surface for straightness.
Tighten head bolts in the correct order as follows:
9 3 1 6 8 <== front of motor 7 5 2 4 10
To tighten follow these steps:
- First time around tighten to 22 lbs/ft
- Second time to 59 lbs/ft
- Loose all bolts completely
- Tighten to 25 lbs/ft
- Tighten to 65 lbs/ft (80 lbs/ft for ARP studs #202-4206)
Before removing the cam sprocket, use nylon ties to run them through a chain link on each side; now run each nylon tie through a top hole in the timing cover, then snug up. This will hold the chain up.
If you have any questions for your KA24DE engine head rebuild, please email us and we can better assist you with parts recommendations based on your current KA24DE Setup.