Hey y'all, I'm running into what seems like a pretty unique issue in my 2006 Evo 9. The other day I was driving home for thanksgiving and while going down the interstate, driving like a grandma, my engine shuts off and smoke blew up everywhere. I pulled to the side of the road and start checking things out, the smoke was no longer pouring out but I noticed smoke coming out of my air box, I figured it was from PCV so I pop the oil filler cap and a decent amount of smoke came out of it. I tried cranking the engine and it felt like there was no compression (no resistance in cranking). I got it towed and started digging into it yesterday, timing belt wasn't snapped (had less than 10K since I did the belt) so I pulled the valve cover and all of my rocker arms are just laying in the head with one of them being broken. Right now my speculation is that for whatever reason the rocker arms fell off causing all the valves to close which then made combustion pressures push past the rings and then make some crazy crankcase pressures causing the PCV to smoke like nobodies business. That's just a theory but my main question is what could cause ALL of my rocker arms to fall off? Thanks y'all!

 

Is your oil level good?

 

Yepp, right at the top notch and the oil was clean

 

I dont see how they could all fall off. Hmmm got me stumped.

 

You've just given it the "bent valve" mod.


There's only 1 other thing that causes that and that's fitting reground cams without washers under the lash adjusters.

 

I haven't done a leak down test to check for bent valves yet but I don't understand how a bent valve would knock off every single rocker

 

I haven't touched the cams since I've owned it haha although that's about to change because the intake cam got nicked by one of the rockers

 

Valves hitting pistons knocks off rockers. If the timing is okay then it was valve float.

GM trucks have valve deactivation. Since no air is coming in it doesn't pressurize the crankcase.

 

I'll have to check the timing on Monday but there's no way the valves were floating at 3,000 RPM haha

 

It's not the valves hitting the pistons that knocks them off directly. It's that the valves are now bent and won't fully close so there's nothing to hold the rockers in place.

If they've ALL fallen off then ALL the valves are bent.

 

your timing belt slipped, pistons hit the valves and knocked off the rockers... I have had the same happen when my aux belt broke and got pulled under the timing belt..

all your valves are bent, guides broken... you will be lucky if the cams are not damaged.. but I doubt it..

I bet you did not change the cambelt tensioner when you did the belt..

 

Makes sense but why would all of my valves bend at the same time while I'm in grandma mode going down the interstate?

 

The intake cam is damaged but I replaced everything when I did the belt

 

it will look something like this

 

I have had it happen at 3000 rpm or less..

when your timing goes 90 deg off ALL pistons get hit within 2 crank revolutions... doesnt matter if you are racing or driving miss daisy, it is an interference engine and valves will bend..

your guides will break too.. good time to replace them