I want to check my cam lobes (stock cam)

[Dhos1]

Remove valve covers, crank motor, but what am I specificallly looking for? What should the VT be doing?

 

[750H.P.V6]

To do it right you really need to pull the intake manifold. Then you'll need to remove the rockers and pushrods to inspect the contact face of the lifter and cam lobe itself for abnormal wear.

Neal

 

[Dhos1]

Thanks

 

[Turbo6inKY]

Thanks

You can do it without pulling the intake manifold. Pull the valve covers and mount a dial indicator on the top of each rocker's pushrod side. Spin the engine around by hand and watch the lift.

if it's where it's supposed to be, you're good. If a lobe has gone flat, it will be very obvious.

 

[750H.P.V6]

You can do it without pulling the intake manifold. Pull the valve covers and mount a dial indicator on the top of each rocker's pushrod side. Spin the engine around by hand and watch the lift.

if it's where it's supposed to be, you're good. If a lobe has gone flat, it will be very obvious.

You can do this but you won't catch a lobe that is starting to fail. You will only find a cam that is well worn out.

Neal

 

[Turbo6inKY]

You can do this but you won't catch a lobe that is starting to fail. You will only find a cam that is well worn out.

Neal

I don't think this guy is looking for a cam that's still working.

 

[Dhos1]

What i am trying to do is inspect this cam before I install some heads on it, and was hoping to find ways to tell if the cam is wearing. ZDDP was always used by previous owner and I use VR-1 oil. It is a 89k mile unopened motor. I do not want to swap a cam if I do not have to as she seems to be running great...

 

[TURBOELKY]

If you're installing heads, its all coming apart anyways. Do like Neal said. Inspect lifter and lobe just do one at a time and don't mix the lifters up. They have to stay with their respective lobe.

 

[Dhos1]

If you're installing heads, its all coming apart anyways. Do like Neal said. Inspect lifter and lobe just do one at a time and don't mix the lifters up. They have to stay with their respective lobe.

Understood!

 

[earlbrown]

What i am trying to do is inspect this cam before I install some heads on it, and was hoping to find ways to tell if the cam is wearing. ZDDP was always used by previous owner and I use VR-1 oil. It is a 89k mile unopened motor. I do not want to swap a cam if I do not have to as she seems to be running great...

There is NO WAY I would touch that camtrain! You have a cam made out of good material with lifters with hardened feet that have work hardened and married to each other. That setup can not be replicated.

If you want piece of mind, get a magnetic base and a dial indicator as stated above. You'll need to pull the rocker shafts to get an accurate reading. if not the springs will compress the cups and you'll get a false reading to the low side.

If all 6 intakes and all 6 exhausts read the same, you're good.


After 30 years and that many miles, if your cam was bad, you'd know it. They don't slowly go flat. They start to wear a little, then all hell breaks loose with a quickness. Lobes are almost like light switches.

 

[robertf]

With all thats been said here, I'll add my .02. I am in the process of doing a headgasket refresh, {blown pass side}. Once apart, I pulled each lifter out and inspected them. At 74,000 they look absolutely brand new. I'm truely amazed at what ZDDP does to preserve the internals. The timing chain has been replaced a few years back but thats it. I would love to have installed a 206 hydraulic roller but could not find a reason to tear down any further.

 

[Buick Mark]

If theres no noise, and it idleoth, pulls good, leave it