Replacement motor questions but hopefully fixable

[rockdogz]

Can we back up a minute?

I understand you swapped coils, but did you verify spark was actually going across the strap at the spark plug?

Other than a collapsed lifter, you have ruled out pretty much everything else. So now it's a matter of verifying the result.

How would you verify the spark?

 

[Tonyrodz]

How would you verify the spark?

Probably as easy as sticking a screwdriver in the spark plug wire and grounding it against metal, then cranking it.

 

[TollKeeper]

Probably as easy as sticking a screwdriver in the spark plug wire and grounding it against metal, then cranking it.

Correction, grounding it near metal, and having someone crank the engine while you watch for spark. If it's on the metal, you won't see the spark. You want to see a bright blue spark.

 

[wsteele]

Can we back up a minute?

I understand you swapped coils, but did you verify spark was actually going across the strap at the spark plug?

Other than a collapsed lifter, you have ruled out pretty much everything else. So now it's a matter of verifying the result.

He pulled the valve cover and verified the rockers are operating properly.

 

[Tonyrodz]

Correction, grounding it near metal, and having someone crank the engine while you watch for spark. If it's on the metal, you won't see the spark. You want to see a bright blue spark.

Yes. I'm terrible at explaining things in detail.

 

[rockdogz]

#2 exhaust lifter. Think this is it?

 

[wsteele]

View attachment 347780#2 exhaust lifter. Think this is it?

You mean #4?

#2 isn't an AFM lifter, like you have in your hand.

Is it collapsed?

Edit: and, yes, it IS a problem, if not THE problem...

 

[89Suburban]

Ouch.

 

[rockdogz]

You mean #4?

#2 isn't an AFM lifter, like you have in your hand.

Is it collapsed?

Edit: and, yes, it IS a problem, if not THE problem...

Yes sorry I meant 4. It’s not collapsed so I’m suspecting it ate the cam lobe since I can’t think of another explanation. Going to inspect it next.

 

[wsteele]

Yes sorry I meant 4. It’s not collapsed so I’m suspecting it ate the cam lobe since I can’t think of another explanation. Going to inspect it next.

It definitely made the cam NG. Bummer, sorry for the bad news.

 

[wsteele]

You are going to get a lot of advice to do an AFM delete, Black Bear Tune, etc. Just be aware, CA is really starting to turn the screw on emissions compliance (and not just that your Truck doesn't produce any more smog than a stock one), they are really starting to look at any mods very tough.

If you decide to go down that road (versus fixing what you have with stock parts), get to know some of the more technically capable members (like @Doubeleive) who also happen to live in CA.

 

[rockdogz]

You are going to get a lot of advice to do an AFM delete, Black Bear Tune, etc. Just be aware, CA is really starting to turn the screw on emissions compliance (and not just that your Truck doesn't produce any more smog than a stock one), they are really starting to look at any mods very tough.

If you decide to go down that road (versus fixing what you have with stock parts), get to know some of the more technically capable members (like @Doubeleive) who also happen to live in CA.

Thanks I’m planning to keep it stock

 

[rockdogz]

Doesn’t look good, I suspect the lobe is gone. Think I can get away with just replacing the cam?

 

[Rocket Man]

Doesn’t look good, I suspect the lobe is gone. Think I can get away with just replacing the cam?

I would think you’d be ok with a cam and lifters. You did get a bit of metal in the oil but it’s not much and the filter should have caught it or the pickup tube screen. I’m no expert though so hopefully someone with more know how will chime in soon.

 

[wsteele]

I am no expert as well, but if it were me (likely will be one of these days), I would budget an OE cam, all new OE lifters (updated AFM lifters), OE VLOM (updated version). I would also put a new Melling oil pump in (which would mean dropping the pan, so I would install the AFM relief valve deflector), new pickup tube O ring, new pan gasket. At that mileage, if you have a trusted machine shop that isn't slammed (unlikely), I would have them freshen the heads as well, but that just a nicety. I would also seriously consider a new timing chain and tensioner, depending on how much service they have already seen, again, just pay me now stuff.

I am not sure if they make 3 bolt stock AFM cams, but if they do, I would go that way (easier to install), which would mean a new cam sprocket (which I would probably do anyway with the new chain).

 

[Tonyrodz]

I am no expert as well, but if it were me (likely will be one of these days), I would budget an OE cam, all new OE lifters (updated AFM lifters), OE VLOM (updated version). I would also put a new Melling oil pump in (which would mean dropping the pan, so I would install the AFM relief valve deflector), new pickup tube O ring, new pan gasket. At that mileage, if you have a trusted machine shop that isn't slammed (unlikely), I would have them freshen the heads as well, but that just a nicety. I would also seriously consider a new timing chain and tensioner, depending on how much service they have already seen, again, just pay me now stuff.

I am not sure if they make 3 bolt stock AFM cams, but if they do, I would go that way (easier to install), which would mean a new cam sprocket (which I would probably do anyway with the new chain).

Don't forget replacing the trays too. Might as well.

 

[wsteele]

Don't forget replacing the trays too. Might as well.

Definitely, hence the I am no expert qualification.

 

[Rocket Man]

Definitely, hence the I am no expert qualification.

You definitely know more about the AFM engines than I do. I’ve never owned one so I’ve never had the need to learn. I don’t live in Cali though and I’d remove all of it myself. My neighbor just bought a ‘12 Yukon Denali from a private party and his engine is exhibiting signs of imminent lifter failure.

 

[wsteele]

You definitely know more about the AFM engines than I do. I’ve never owned one so I’ve never had the need to learn. I don’t live in Cali though and I’d remove all of it myself. My neighbor just bought a ‘12 Yukon Denali from a private party and his engine is exhibiting signs of imminent lifter failure.

I understand that point of view for sure.

I have been pondering this stuff for a while and I think the choices people make probably are driven as much by which set of fears dominate their thinking, as anything else.

Having lived a big chunk of my life off and on in CA and watched the state evolve, I can say with great certainty, the fear of the bureaucrat's jackboot on my windpipe is far greater than the fear of a collapsed AFM lifter. Any choice I made on this front would have to include a non-invasive way back to stock, just knowing that the CARB folks never sleep in their quest to get that jackboot squarely planted on the neck of every citizen in the state (and beyond).

For me here in Idaho, the picture is a little less clear cut for certain, but still, when I ponder the valve train future of my bone stock 2007 Yukon (first get AFM), I do know one option for me when that P0301, 4, 6, 7 pops up is just to install all new OE stuff with all appropriate updates and drive on. I will have gotten 150K+ miles out of the first set of down rev lifters and VLOM. With the same or better maintenance along the way, another 150K+ miles out of the next gen set of AFM lifters might take me all the way to a brand spanking new reman from none other than GM themselves, pretty far down the road...

 

[Rocket Man]

I understand that point of view for sure.

I have been pondering this stuff for a while and I think the choices people make probably are driven as much by which set of fears dominate their thinking, as anything else.

Having lived a big chunk of my life off and on in CA and watched the state evolve, I can say with great certainty, the fear of the bureaucrat's jackboot on my windpipe is far greater than the fear of a collapsed AFM lifter. Any choice I made on this front would have to include a non-invasive way back to stock, just knowing that the CARB folks never sleep in their quest to get that jackboot squarely planted on the neck of every citizen in the state (and beyond).

For me here in Idaho, the picture is a little less clear cut for certain, but still, when I ponder the valve train future of my bone stock 2007 Yukon (first get AFM), I do know one option for me when that P0301, 4, 6, 7 pops up is just to install all new OE stuff with all appropriate updates and drive on. I will have gotten 150K+ miles out of the first set of down rev lifters and VLOM. With the same or better maintenance along the way, another 150K+ miles out of the next gen set of AFM lifters might take me all the way to a brand spanking new reman from none other than GM themselves, pretty far down the road...

I can’t help but to compare the prior generation of LS engines before they introduced AFM that run 400-500,000 miles with basic maintenance. So in my mind, I would have to delete all that unnecessary and complicated crap that’s only there to bring GM’s overall fuel mileage into the EPA’s guidelines. The fuel savings aren’t worth it IMO. I’d rather have a solid design that lasts pretty much forever. I wouldn’t even wait for failure either- I’d delete it immediately. I did go through that decision phase when I was looking for a bagged NNBS Silverado and had come to the conclusion that if the truck I ended up with had AFM, a full delete was one of the first things that I would do, and while I was in there I’d do a nice cam to add more power. Luckily the truck ended up without AFM but I still did the cam. As far as California…the more I’m reading about their ability to read the ECM tune and compare it to a stock one and reject emissions if it has been altered means to me that any engine that isn’t stock in that state is not going to be on their highways for much longer. I’ll never live in a state that does that.