2004 impreza 2.5rs

[Superman04wrex]

My timing belt wen out on my rs while I was starting it. Any idea weather this engine is an interfierence or a free wheel style engine? If it is interfearence style is ther a way to pull off the heads so I can rebuild them without pulling out the motor?

[Durania]

It is an interference engine and yes you can pull the heads without pulling the motor.

[Superman04wrex]

I'm trying to put in the new timing belt but I don't see the timing marks on the engin block. Do I just need to line up the marks on the pulleys with the marks on the new belts? And if I need to pull out the heads for service how can I do it without pulling the engine?

[Danbob99]

The engine is a single cam motor, under the slow rpm of cranking it is pretty unlikely that you would interfere valve to pistion. A new timing belt install will certainly tell the tale.

 

As far as timing marks, there is a mark on each cam, on the right side of the motor (passenger side) Line up the mark to the crack between the cam case and the head. On the passenger side there is a small tick at the top of the inner timing belt cover.

 

I generally use the marks on the new belt and align them with the cam and crank marks exclusively. If those are lined up right, the belt is on.

 

If you need to pull the heads, it is a bit tougher to do in car, but if you don't have the ability to pull the motor, it is certainly do-able.

Remove the intake manifold

Remove the exhaust manifold.

Undo the engine mount bolts so you can jack up the motor on one side and cock it sideways, to make getting to the headbolts easier. You do not have to do this, but it makes work a lot easier.

Pull the heads, replace damaged valves.

 

While doing your timing belt, be sure to check your timing belt tensioner to be sure that wasn't the source of your broken belt.

 

Dan