Flat tappet cams have been used for decades without having constant failures so long as they are properly lubricated and not overloaded. So I wouldn't say that roller bearings are a requirement.
I agree with you guys. Cold starts could be a big contributor. Probably why that one oil filter adapter thing (Baxter) would be a good mod
Agree!! I think Jeep needs to hire us.
And get heat, lots of it. My use of 0w20 always had oil temperatures leading coolant temps when above 3000 rpm. Interestingly, using 5w30, oil temps now lag coolant temps above 3000 rpm.
From the picture of failures that I've seen I don't see excessive heat. Typically a high heat failure of lubrication will cause the parts to get a varnish, or the metal to get hot enough to discolor. I don't see that, it just looks like someone slowly ground away at the lobes with abrasive material over time.
Doing the gas + brake trick to turn the engine over and get the oil pump going for 10s before starting it is WAY cheaper than the Baxter. It's free.
Just when I thought the extended cranking trick days were over for me after I replaced cam phasers on my last 3.5 Ecoboost truck I owned
Meh not entirely.
Ok, never heard this one. Just depress both a few times before starting? I'll do any trick needed to get rid of that tick on startup. It's maddening, makes me think of developing cam problems every time I hear it.
Hold gas and brake to the floor, press start button like you were starting it like normal. Keep both depressed and starter will run for ~10 seconds and crank the engine without firing. If you want to run multiple times you can, just release pedals between runs.
I agree, that camshaft looks like a lot of copper is showing, not what I expect a cam to look like, goes back to metallurgy.
Thank you, sir. I will certainly give this a try. My JLR is not a daily driver, and situation is similar to yours but not kiddo-related. My only concern is dry-cranking the engine for 10 seconds or so. But I guess that's the idea; to get the oil moving to the important bits before the rpms skyrocket.
I would guess that it is in a low pressure area for the oiling network. So last to get oil on startup. I do definitely think that it is a heat treating issue contributing to it the more I look at it. The slipper shows very little wear, and the cam surface doesn't exhibit any signs of proper treatment and overloading that is typically present in cam failures with proper hardening. As to why we don't see it on every engine and it's just hit or miss... That's a bigger mystery. Could be that the oven that they put them in to create that tempur during the heat treatment process has a cold spot that only affects some of the cams out of a batch or some other similar anomaly.
Do you know what the conditions are for the VVL system going into high lift? Thought occurred to me that as much wear as was on the pictured cam from earlier would require probably significant time where the roller shoe or whatever you wanna call it is in contact with the cam. Wonder if it's in contact with the cam when it shouldn't be and that's when it's wearing. Stuck partially up or something, due to a peculiarity of the oiling system or even a software fault if the solenoid state is wrong or something.
