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View Full Version : *HOW TO* Change a 8v Cam/Lifters WITHOUT removing the head



Adam
14-02-08, 07:21 PM
This was done by Benji quite a few years back, i found a copy i saved at the time, an a file host account. So thought it may be useful to people.


Seeing as so many people always ask how to change a cam without taking the head off i thought i would do a guide.

there are probably better way's of doing this but i don't care, this is the way i have done it a few times now and it works for me.

firstly i marked the dizzy position and removed it, along with the leads and the plugs.

then i removed the cam cover, 8x m8 bolts, i will change the gasket when i refit as it leaks like a bitch, they cost about ?4 from any motorfactors

next thing off was the cam belt cover.

now using a 17mm spanner i turned the engine over to TDC, basically it is when the line at the top of the cam pully is at the top, and the mark on the crank pulley is next to the mark on the cam cover.

using my high tech tdc meter (mig wire) i turned the cam pulley untill all piston's were level.

i then marked the pulley and belt at the top
http://img.photobucket.com/albums/v86/Nova-crew/PNG%20How%20To%20Pics/Image1.jpg

next job was to remove the cam pulley, on a vauxhall cam there is a place to put a 22mm spanner(might be 24mm i can't remember) as mine i a piper cam i don't have one. all i have to work with is a slot in the end of the cam.
http://img.photobucket.com/albums/v86/Nova-crew/PNG%20How%20To%20Pics/Image2.jpg

so i had to make a tool to fit.

a bit of a bodge but it works. once you have your cam braced you can undo the 17mm bolt on the pulley, remove the pulley and the belt, but be sure not ot disturb the belt positon on the crank pulley.

now you can start removing the followers. to do this you need a special tool. mine is made by laser and cost around ?8. i have 2 but it's eaiser to work with 1 at a time.
http://img.photobucket.com/albums/v86/Nova-crew/PNG%20How%20To%20Pics/Image3.jpg

this bolts into the hole that the cam cover bolts to, the curved part sits on the valve spring cap. you then tighten the small nut and the valve is pushed open, this moves the follower off the cam, and you can remove it with your fingers or some long nose pliers.
http://img.photobucket.com/albums/v86/Nova-crew/PNG%20How%20To%20Pics/Image4.jpg

i started by removing all the followers that were on a closed valve

http://img.photobucket.com/albums/v86/Nova-crew/PNG%20How%20To%20Pics/Image5.jpg

once i had reomved all of them i put the 17mm bolt back in the end of the cam and turned it so the remaing followers were on closed valves, this is why i set the piston's to half height, so i could open all the valves as much as possible.

http://img.photobucket.com/albums/v86/Nova-crew/PNG%20How%20To%20Pics/Image6.jpg
http://img.photobucket.com/albums/v86/Nova-crew/PNG%20How%20To%20Pics/Image7.jpg

if you are refitting the followers and not replacing them you must fit them in the same place they came from, i had a spare head in the garage so i could sit them on the same valves they came from.
http://img.photobucket.com/albums/v86/Nova-crew/PNG%20How%20To%20Pics/Image8.jpg

once you have all the followers out you can also remove the followers seat's(thrust pad's i think is their proper name.) these also need replacing in the same place as they came from.

when it looks like this your cam is ready to be removed. you have to remove the 2* 5mm allen bolts at the dizzy end of the cam and remove the locating plate. then tap the cam fro the pulley end out using a nylon mallet, the cam should slide out, but you might have to move the washer bottle to get it out.
http://img.photobucket.com/albums/v86/Nova-crew/PNG%20How%20To%20Pics/Image9.jpg

i hoe this helps with anyone wanting to change a cam.



-Just to add a few points myself, when refitting the new cam make sure its well lubed( ohhh ahh,Lol)
-And if fitting new lifters, compress them a few times in a tub of clean engine oil.
-The tool used to compress the valve spring can be bought off ebay/draper stockist for around ?10, and is called a "Valve play compensator"
-To stop the cam moving whilst trying undo the cambolt, play a socket extension through a hole in the cam sprocket, and wedge it against the cam housing cast screw hole.
-And before removing the cam pully, you will need to take the tension out the cambelt, either by loosening the waterpump and turning it(this will need the coolant system topping up, and maybe a new pump seal)
Or loosening the cambelt tensioner if it has one(late engines only)
It is doable without undoing the tension, but its tricky trying to refit the belt.
-And finally, the part about setting the pistons level and NOT at TDC is very important, as the tool opens the valve, which could hit a piston and bend the valve if you tighten the tool with the pistons at TDC :)