Is This Camshaft Reusable? Or Too Pitted?

[jmo2610]

Not necessarily. If yours has VVT, it's probably worth the extra 15 lb ft around town to keep it. In which case, you'll want to keep the factory-style tensioner, though I do recommend replacing it with new. In my case, I was working on a 6.2 and the dyno tests for the cam I used showed no losses down low but nice gains in the midrange and higher, where I need them for towing. So I didn't care about VVT in my application since it's mostly for fuel economy on these anyway.

All of this reminds me - I don't think we ever established which model year and engine you're working with.

Mine is a 2013 Yukon XL Denali. 6.2

 

[West 1]

Unless there is hidden damage not shown in the photo that is what used roller cams look like. With roller lifters they do not wear down. Failed roller cams are caused by a bad lifter. Owners run the broken AFM lifters while they are clacking till the cam gets damaged. Does not look like you did that. The cam would run 300,000 miles or much more. If they could just provide lifters that could do that also............ And it would be nice if they modified the block so we could change these dang lifters without pulling the heads.

 

[Just Fishing]

Mine is a 2013 Yukon XL Denali. 6.2

VVT?

 

[Just Fishing]

Non VVT camshaft: https://www.summitracing.com/parts/nal-12638427
I believe this is the one I'm running in my 6.0, I like it.

ETA: Well that's the 3 bolt version, I have the single bolt... I'm not finding it doing a quick search.

 

[West 1]

The cam looks fine to me, if you don't think it is good have a shop polish it, it will look brand new again. Roller cams last one heck of a long time. The same design goes into the Duramax Diesel, no one tears them down for a cam and they last 300,000+ miles. Not saying it is pretty but I don't see anything on that cam that will make a lifter wheel fail. Roller cams are durable. When I see bad ones it is because the owner had a bad lifter and kept driving it while it was broken till the bad lifter did damage to the cam surface.
Every lobe needs close inspection to make sure you don't have hidden damage. It sounds like you already made a decision to install a new cam. At least the Non AFM lifters cost much less!

 

[jmo2610]

VVT?

Yep. Deleting the VVT, too. I decided to go ahead and replace everything, so 3-bolt cam, new sprocket, new chain damper.

 

[jmo2610]

The cam looks fine to me, if you don't think it is good have a shop polish it, it will look brand new again. Roller cams last one heck of a long time. The same design goes into the Duramax Diesel, no one tears them down for a cam and they last 300,000+ miles. Not saying it is pretty but I don't see anything on that cam that will make a lifter wheel fail. Roller cams are durable. When I see bad ones it is because the owner had a bad lifter and kept driving it while it was broken till the bad lifter did damage to the cam surface.
Every lobe needs close inspection to make sure you don't have hidden damage. It sounds like you already made a decision to install a new cam. At least the Non AFM lifters cost much less!

Jesus I almost wish you wouldn't have said all this. I'm already waayyyy too deep now.

 

[j91z28d1]

Jesus I almost wish you wouldn't have said all this. I'm already waayyyy too deep now.

if it helps. your lifters was toast and you can't run a non afm lifter on a afm cam. so you'd have had to replace the afm lifters with new ones. all the aftermarket ones fail almost instantly, so oem dealership, which I believe are 800$ a set these days. and then if you're like I just put new lifter in it. I may as well leave afm enabled. you'd want to replace the vlom too. that's a few 100 more and then a 100k from now it fails all over again.

 

[Geotrash]

if it helps. your lifters was toast and you can't run a non afm lifter on a afm cam. so you'd have had to replace the afm lifters with new ones. all the aftermarket ones fail almost instantly, so oem dealership, which I believe are 800$ a set these days. and then if you're like I just put new lifter in it. I may as well leave afm enabled. you'd want to replace the vlom too. that's a few 100 more and then a 100k from now it fails all over again.

This. You’re getting rid of the problem system.

 

[jmo2610]

Do you guys know if local stores sell the red pickup tube o-ring? My pump came with two black o-rings... am I supposed to stack those?

 

[Blackcar]

Do you guys know if local stores sell the red pickup tube o-ring? My pump came with two black o-rings... am I supposed to stack those?

If you have gm dealer in your town I would go there they will have one you need.

 

[j91z28d1]

If you have gm dealer in your town I would go there they will have one you need.

this is what I did on my ls3 car when I happened to have the pan off, just buy the dealer one based off the vin.


on a side note. Just curious how did the old one feel you took out?

 

[jmo2610]

this is what I did on my ls3 car when I happened to have the pan off, just buy the dealer one based off the vin.


on a side note. Just curious how did the old one feel you took out?

It didn’t seem to have any cracks in it, but was very flat and left some red rubber on the lift tube where it was seated. Had to spend some time cleaning that off.

 

[Fless]

It didn’t seem to have any cracks in it, but was very flat and left some red rubber on the lift tube where it was seated. Had to spend some time cleaning that off.

Good time to replace it. Although mine was still holding pressure, it was getting flattened and I had it changed when the pan gasket was done.

 

[donjetman]

I have successfully used both of the following o-rings in my 07 6.2L Denali stock pump and pickup tube.
Mahle# B32790 (installed 6/24)
and/or
Felpro# 72401 (installed 12/18)

 

[West 1]

I have never seen a pick up tube with more than 1 Oring. Maybe a previous owner doubled them up?

GM does not make lifters, have not made them in 30 years. Eaton does make Lifters, Top Line USA does make lifters at the HyLift plant, I have used both Eaton and Topline Hylift and they work as well as OEM. I have chosen not to use the Moresa brand from Mexico because 20 years ago they had bad quality, maybe today they are top notch. The China supplied lifters scare me also so I have not used them even though the low price is tempting. Just too much labor to change one if it fails.

BTW: I understand there are two companies using the TOPLine name, make sure you use the USA manufactured brand. Talk to local machine shops that build engines every month. They will have current information on what brands work today.

 

[jmo2610]

Do any of y'all remember how you were able to torque the bottom left front-facing bolt on the timing cover? I can barely even get a tiny wrench on it, much less anything to put some actual torque on it.

 

[West 1]

When you torque the other bolts take a small open end wrench or whatever tool you can get in there with. Test the tool you need to use on the already torqued bolts. Once you know how tight they feel with the wrench you need to use just do the torque on the hard bolt by hand and trust your feel to hit proper torque. Funny, I bet I have done a dozen of those in the past couple years and I do not remember any giving me trouble and no memory of how I did it. When I can't get my torque wrench in place to do the job this is how I do it. You can go back and double check and make sure your bolt done by feel is as tight as those done with the torque wrench.

I am assuming you have the radiator out for room to work?

Do you have swivel sockets? Extensions, short sockets? Most times you can get in there to properly torque the bolts. Sometimes I have to use 1/4" drive sockets as they are smaller and give more access.

 

[jmo2610]

When you torque the other bolts take a small open end wrench or whatever tool you can get in there with. Test the tool you need to use on the already torqued bolts. Once you know how tight they feel with the wrench you need to use just do the torque on the hard bolt by hand and trust your feel to hit proper torque. Funny, I bet I have done a dozen of those in the past couple years and I do not remember any giving me trouble and no memory of how I did it. When I can't get my torque wrench in place to do the job this is how I do it. You can go back and double check and make sure your bolt done by feel is as tight as those done with the torque wrench.

I am assuming you have the radiator out for room to work?

Do you have swivel sockets? Extensions, short sockets? Most times you can get in there to properly torque the bolts. Sometimes I have to use 1/4" drive sockets as they are smaller and give more access.

It was that bolt circled that I had a whale of a time getting to. Just had to do it by feel, once I eventually got an small wrench on it. Not one of my swivels would get in there.

https://imgur.com/a/A8drjM8

 

[jmo2610]

Next question.... how do you hold the harmonic balancer still in order to torque the crankshaft? And 240 ft/lbs on the first pass? I'm gonna have to borrow a heavier duty torque wrench.