304 How hard is it to change a 5lt Cam?

[Deneo]

As title states -

How hard is it to change the cam on a 5 litre? first thing i want to do to mine, but don't want to have to pay when i can probably do it myself. The cars a VS Statesman
Thanks guys
Deneo.

 

[greenfoam]

It's not too hard, the biggest problem is cleaning all the old slime and dirt off things before you put it back together, but the actual putting the cam in isn't hard (changing the valve springs is harder really)

 

[Deneo]

Thanks mate.
Can it be done while the engine is in the car? What needs to come off to change it?

Cheers.

 

[greenfoam]

Well for most cams you will need to change the springs, you can do that with the heads on and turning the motor by hand with rope fed into the spark plug holes (that's how I did it). For the cam in a Commodore you need to pull the radiator out, I pulled the front bar off also since I had other things to do. The intake manifold needs to come off, the belts, the crank pulley, the balancer. Then the water pump and timing over (don't forget the bolts under the timing cover that bolt it to the sump), it's best to leave the water pump attached to the timing cover since that's one less thing to re seal. Then you need to undo all the rockers. At this stage you can slide the balancer back on and get a bar on the crank bolt and turn it over untill the dot on the crank pulley is at 3 oclock(ish will be abit lower than that I think) and the dot on the cam pulley is also at 3 oclock (put this exactly at 3), there will be 9 links between them and the piston with be at TDC on cylinder 1. The rotor on the dizzy will be pointing at Cylinder 5, mark where the rotor is in relation to the dizzy body and where the dizzy body is in relation to the block. Then you may as well pull the dizzy out and clean all the sludge off it so it's easier next time. Then without turning the motor remove the timing gears and chain. Then the cam retaining bolt.

Pull all the lifters out (they will most likely be stuck in with carbon around the base) but you can scratch the carbon off them with a screwdriver and then pull them out which makes it easy, then pull the cam out. Slide the new cam in, put the retaining bolt and nut back on, put your gears and chain back on (or new gears and chain) in the same spot, cam dot at 3 o clock etc.

Then if you have a dial indicator you can check the lift on the intake lobe of the cam at TDC vs the spec sheet that cam with the cam, most mild cams are in the .050 ish of an inch lift at this point but it says on sheet what it needs to be. Oh before you put the cam in, spray all the lobes and base of the new set of lifters with Molly spray lube (there's a picture of it in my thread) and you can use some nulon high pressure grease on the lobes and lifter bases also. Use a oil with zinc additive and some crane cam run in additive also if you want to be triple sure of things. Then reassemble everything.

Once it's run in (20 minutes at 1500-2500 rpm) you can set your timing to be spot on again and that's complete

 

[vyjess]

if ya car has a/c will u need to pull condenser out as well to fit cam or is there enough room once radiator is out?

 

[Deneo]

Well for most cams you will need to change the springs, you can do that with the heads on and turning the motor by hand with rope fed into the spark plug holes (that's how I did it). For the cam in a Commodore you need to pull the radiator out, I pulled the front bar off also since I had other things to do. The intake manifold needs to come off, the belts, the crank pulley, the balancer. Then the water pump and timing over (don't forget the bolts under the timing cover that bolt it to the sump), it's best to leave the water pump attached to the timing cover since that's one less thing to re seal. Then you need to undo all the rockers. At this stage you can slide the balancer back on and get a bar on the crank bolt and turn it over untill the dot on the crank pulley is at 3 oclock and the dot on the cam pulley is also at 3 oclock, there will be 9 links between them and the piston with be at TDC on cylinder 1. The rotor on the dizzy will be pointing at Cylinder 5, mark were the rotor is in relation to the dizzy body and where the dizzy body is in relation to the block. Then you may as well pull the dizzy out and clean all the sludge off it so it's easier next time. Then without turning the motor remove the timing gears and chain. Then the cam retaining bolt.

Pull all the lifters out (they will most likely be stuck in with carbon around the base) but you can scratch the carbon off them with a screwdriver and then pull them out which makes it easy, then pull the cam out. Slide the new cam in, put the retaining bolt and nut back on, put your gears and chain back on (or new gears and chain) in the same spot, cam dot at 3 o clock etc.

Then if you have a dial indicator you can check the lift on the intake lobe of the cam at TDC vs the spec sheet that cam with the cam, most mild cams are in the .050 ish of an inch lift at this point but it says on sheet what it needs to be. Oh before you put the cam in, spray all the lobes and base of the new set of lifters with Molly spray lube (there's a picture of it in my thread) and you can use some nulon high pressure grease on the lobes and lifter bases also. Use a oil with zinc additive and some crane cam run in additive also if you want to be triple sure of things. Then reassemble everything.

Once it's run in (20 minutes at 1500-2500 rpm) you can set your timing to be spot on again and that's complete

Thanks mate! very valuble infromation i'll let you's know when i do it. i have to pick a cam first =D

 

[Troy5L]

well done greenfoam....u should of done a how-to writeup when you did ur's.

 

[Warranty Void]

Just drill a cam sized hole thru front of car.

 

[greenfoam]

For a big stato you want to be looking at cams that will concentrate the power in the 1500-4000 rpm range, something small on the duration around 213 with agressive lobes and a tight LSA 110 or maybe even a bit less will be about what you want. Just something that can make it move off the line

 

[greenfoam]

well done greenfoam....u should of done a how-to writeup when you did ur's.

Should have but grease, slime and SLR cameras don't really mix and going in and out of the shed wasn't seeming like much fun at the time but I do remember everything and can answer questions about it