Idle stumble when cold...And other stuff

[Rawze]

(03-07-2017 )dhirocz Wrote:  OK so I need a new cam. Rocker was on its way out on #1 exhaust but hadn't scarred up the cam yet. But when I rolled the engine over, I found the same on the #5 intake...Which started to eat the cam.

With 685k on it I need to decide what direction to take. I'm fairly disappointed, seeing as I've made sure to change oil every 15k or less, have done multiple oil analysis done which all came back clean, run a filter mag, and run a bypass filter and this still happened. At least I caught it earlier rather than later. Had the truck since 607k.

Cam lost about .030" off the lobe.

If I decide to replace, I suppose I should plan for a new cam, rocker arms, drop and flush the pan, inspect/ replace the oil pump and replace the oil cooler...? I would also pull a couple caps and check the bearings while the pan was off.

you have 685k on it, it has 605 k you say when you got it. The damage was done long before you purchased it from what it sounds like. The bad lobes are likely due to plugged cross-channels in the rocker arm and worn out bearings, lowering the pressure to the whole rail.

There are solutions like shimming the pump and running a gallon of gear lube to raise hydraulic pressure ratings and protect the cams. Question is do you want to invest in it, get it right again, and own it long term. If so, then don't be shy about it, or you will continue to do nothing but chase your tail. I see too many on this forum that have been there and done that.