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The car is a 2014 Z51 mt with 14k on the clock. While driving the car through the gears, shifting from 2nd to 3rd ,the car started running rich and rough. I pulled over and heard noise from the passenger cylinder area. Shut it down and had it towed home, (only three miles.) Read code and got P0106. Decided to pull the valve cover from the passenger cylinder thinking that I may have a broken spring, but I had a completely broken #2 exhaust valve.
Is there issues with these valve, should I upgrade?
Slight grove on the piston but was able to clean it up with 400grit sand paper
I think at the very least it would be worthwhile to have a machine shop check them as well as the head and valve guides. I'm no expert with machining and things with this nature but some kind of stress I would think caused that particular break. Hopefully someone can chime in here with a possible explanation.
I think at the very least it would be worthwhile to have a machine shop check them as well as the head and valve guides. I'm no expert with machining and things with this nature but some kind of stress I would think caused that particular break. Hopefully someone can chime in here with a possible explanation.
Know so far that the effected valve, valve guide is worn. Probably replace them all, go with new springs and locks and upgrade push rods. Not much available when your trying to stay close to stock.
I bent an exhaust valve on my 16 Camaro which was a Magnuson SC Lt1 and it stuck open. So I pulled the head to check it nicked the piston just a little so I ordered just one GM exhaust valve and reshimmed the valve spring. I put it back together and was good to go. I did clean up the piston with a little sand paper and never had any issues again. The motor made over 850 rwhp so I punished it plenty after the replacement.
Last edited by 99vetteran; May 8, 2021 at 11:35 AM.
I bent an exhaust valve on my 16 Camaro which was a Magnuson SC Lt1 and it stuck open. So I pulled the head to check it nicked the piston just a little so I ordered just one GM exhaust valve and reshimmed the valve spring. I put it back together and was good to go. I did clean up the piston with a little sand paper and never had any issues again. The motor made over 850 rwhp so I punished it plenty after the replacement.
How were the spring re- shimmed went using hat type guide valve seal? Did you use different seals? None of the springs on my heads have any shims.
How were the spring re- shimmed went using hat type guide valve seal? Did you use different seals? None of the springs on my heads have any shims.
When the machine shop checked the valve springs that one was not the correct height and spring pressure needed to be shimmed to correct the issue. It happened because I was roll racing back to back to back and the Camaro was spinning the drag radial pretty hard in second on the launch and was over revving and think that caused the valve to hit the top of the piston and bent the valve. No other damage except it did nick the piston and bent the valve. Still enough to cost me a few bucks to fix it.
Another way to look at this problem is to ask the question is it cheaper to have both heads removed, inspected and repaired than it is to replace the engine? Next time you may not be so fortunate.
We run into bent valves from time to time when we do cam swaps. But to see when crack in half is very rare. I would say have the head inspected and rebuilt but you can probably find a used replacement if you look around.
Thats what I'd do, have them look at that head and make sure the spring have the correct height and pressure as the rest of the springs. As long as there is not other damage you can probably get away with just the one exhaust valve. If for some reason there are other issues where the head needs to be resurfaced pull the other head and have it inspected and resurfaced also. Its a lot of work and getting it done right is the most important thing. Because if it damaged the chamber or a guide that head will need some work.
Last edited by 99vetteran; May 10, 2021 at 10:40 AM.
Another way to look at this problem is to ask the question is it cheaper to have both heads removed, inspected and repaired than it is to replace the engine? Next time you may not be so fortunate.
I also broke an Exhaust Valve...I would definitely replace ALL the hollow exhaust valves with a good strong inkodel valves on Both cylinder heads....!!! Also upgrade the valve seals to the CHE bronze valve guides, they are much better than stock, and many people believe that the valve guides wear which is causing the valve stem to not sit properly in the head which is causing it to bend and break.... Of course you should change the valve springs and also upgrade the lifters to a good set of Johnson ( part # 2116, the ones with the t-bar, You also have to remeasure for push rod length), while you're in there for a trouble-free valve train for years to come..!
I also broke an Exhaust Valve...I would definitely replace ALL the hollow exhaust valves with a good strong inkodel valves on Both cylinder heads....!!! Also upgrade the valve seals to the CHE bronze valve guides, they are much better than stock, and many people believe that the valve guides wear which is causing the valve stem to not sit properly in the head which is causing it to bend and break.... Of course you should change the valve springs and also upgrade the lifters to a good set of Johnson ( part # 2116, the ones with the t-bar, You also have to remeasure for push rod length), while you're in there for a trouble-free valve train for years to come..!
That was two years ago. I replaced both heads with new oem ones not rebuilt. They came with the the new blue springs. So far, all is good.