Camshaft replacement questions

[coronan]

Are 3y and 4y camshafts the same?

Can the cam be changed with out removing the head?

Or will the lifters fall down???

I want to see if i can get one custom ground with out taking my van out of service.

Thanks!

[timsrv]

I've not tried to remove a cam from a 3y/4y installed in a van yet, but you will need at least 2 feet clearance in front of the block. Removal of the radiator and/or condenser will be mandatory, but can't say for sure if that would be enough (I'm guessing it would). As for removing the head, it's not required, but all the lifters would need to be removed 1st or they could/would fall down into the block. In order to remove them you'd need to 1st remove the valve cover, rocker assembly, all the push rods, the spark plugs and the spark plug tubes. Pulling the spark plug tubes helps with access and also helps you see what's going on. As you might already know, some lifters can become hopelessly stuck in their bores but some will slide right out. Hopefully yours will come out easily. Tim

[coronan]

Thanks tim!

I expected to remove the radiator. The Cam comes out with a slide hammer right? Cam Bearings?

As you remember from another thread my block uses Roller Lifters. They are retained by some plates that keep the roller from rotating in the bore.
Those plates also keep the lifters from being removed with the head on. (This stumped me for a while. Several hours trying to remove the lifters through the head. Once i did a head gasket it was obvious.)

So My head will have to come off.

What special tools do i need?

[timsrv]

Oh yes, I recall that now. Even so, the lifters will need to be removed or they will hit on the cam lobes/bearings and not allow camshaft removal. With the lifters out of the way (and in your case perhaps the head) the cam will slide right out. Of course there's the timing cover and cam gear/thrust bearing that will need to come off, but that's all pretty self explanatory. When I do this with the engine out, I always put the engine up on end (front of engine facing up). This way gravity helps keep the cam straight to the block and lessens the chance of damaging cam bearings. With the engine installed, you should find a big bolt to use as a handle. This should help prevent the lobes from dragging on the bearings until it's far enough out to handle (then you can take off the bolt). Tim