cam change question.

[robmog]

how long would/should it take to change cams?
anyone got a link or list of the steps?
I have waynes book and could probably figure it out, after rebuilding my 2.4 E engine.
but it never hurts to ask first.
thanks.

[mreid]

It a one day job if you have all the tools, know how to use them and know you won't have any valve train clearance issues.

[Henry Schmidt]

I remember back in the day, changing the cams in an early 911 without even removing the engine.
We put the car up on jack stands, disconnected the shift linkage and lowered the back of the engine on a floor jack.
Pulled the muffler, rear engine tin, the engine cradle, valve covers and chain box covers.
All told it took 2 guys about 3 hours and a case of beer, IMSM.

[Tippy]

Originally Posted by Henry Schmidt

I remember back in the day, changing the cams in an early 911 without even removing the engine.
We put the car up on jack stands, disconnected the shift linkage and lowered the back of the engine on a floor jack.
Pulled the muffler, rear engine tin, the engine cradle, valve covers and chain box covers.
All told it took 2 guys about 3 hours and a case of beer, IMSM.

I assume the rockers were not changed out?

[Henry Schmidt]

Originally Posted by Tippy

I assume the rockers were not changed out?

I'm not sure why you would assume that, all rockers were removed?
The reason they weren't replaced is that up until recently (last 8-10 years) rockers were never an issue.
The only time a rocker was replaced was when a oil tube got clogged and the rocker/cam lobe would eat each other or when welded cams were used.
Rockers broke during over-rev but rarely failed do to wear.
Major rocker failure is an entirely new phenomenon. I assume the issue is oil quality more than materials used.
We would occasionally see a void (pit) in a rocker pad starting in the early 80s but that was pretty rare as well.

[Tippy]

So the older rockers were no problem to run a new cam without resurfacing?

[robmog]

I have a cam tower oil leak and figure to fix that I have to remove the timing chains.
So while I'm at it, I might want to install a sportier cam.

[Henry Schmidt]

Originally Posted by Tippy

So the older rockers were no problem to run a new cam without resurfacing?

New, reground and used factory cams.

[Henry Schmidt]

Originally Posted by robmog

I have a cam tower oil leak and figure to fix that I have to remove the timing chains.
So while I'm at it, I might want to install a sportier cam.

Cams are the number one factor in determining the character of your engine. If you want to change the character, cams are the best way.

[Tippy]

Originally Posted by Henry Schmidt

New, reground and used factory cams.

Ok, thanks.

Many here recommended to resurface the rockers so the wear pattern of the old rocker wouldn't transfer to the new cam - hence original question as changing out the rockers with the engine in would be pretty tough.

[Henry Schmidt]

Originally Posted by Tippy

Ok, thanks.

Many here recommended to resurface the rockers so the wear pattern of the old rocker wouldn't transfer to the new cam - hence original question as changing out the rockers with the engine in would be pretty tough.

Prior to the oil deficiencies of the past decade and 1/2, cam wear was of minimal concern.

As for changing the rockers in the car, it is doable as my story indicates. You can't change cams without removing the rockers.

[Tippy]

Ah, I thought you could pull the cams without rocker removal with a little patience and rotating the cam lobes back forth.

That's silly quick in 3 hours then!!

[boyt911sc]

Originally Posted by Tippy

Ah, I thought you could pull the cams without rocker removal with a little patience and rotating the cam lobes back forth.

That's silly quick in 3 hours then!!

Tippy,

I was pulling out the cam and left the intake and exhaust rockers for cylinder #3. Expecting that by rotating the cam, I could wiggle the cam out. But I failed to get the cam to slide out after several minutes of trial and error. I still could not figure out why up today. So by removing all the rockers, not only it is convenient to remove and install the cam/s, you save a lot of time and frustration from trying to get the cam out with rockers installed.

Tony

[Tippy]

Right on. Thought I was able to slide a cam out in my 3.2 during rebuild, but I guess not.

[Henry Schmidt]

Originally Posted by Tippy

Right on. Thought I was able to slide a cam out in my 3.2 during rebuild, but I guess not.

The issue is the diameter of the bearing journals, rotating them makes no difference.

[Andy 930]

With the tools required and to dial a new cam in correctly,the engine would be on a stand in my shop.
New rockers too. That way there isnt a oil leak in sight. Slippery slope but new chains would be good too,not a fan of the chains with the joiner in... seen that little clip stuck to a magnetic plug once before... Game over,insert more money..