I don't have much experience with this engine (yet)...and don't want to, to be honest. But, other DOHC engines I've worked on are as you describe - rockers sit "loose" between cam and lifter. I think you're fine.
Replacing timing chain, discovered rocker arms came off
I'm many, many, many hours into replacing the timing chain on my 2011 Enclave. I was starting to replace the timing components when I happened to notice that 3 of the rocker arms had come completely loose and were at the bottom of the head. This was on the same side of the engine that the looser of the two chains were.
I'm wondering how bad this might be, particularly if this means potential valve or piston damage. I've never done this type of engine work before and am not sure how loose those rocker arms should be, but they don't appear to be bolted on or anything. I took off the camshaft and noticed they all fit pretty loose.
My assumption is that those arms are supposed to be loose and as long as the car is in time, the cams are positioned in a way where there is enough force on them to prevent them from coming out. If that's they case, it ought to be good enough to just reposition the arms, get the camshaft back in place, do the timing chain work, and call it a day.
I don't know if this is wishful thinking though. Has anyone doing the dreaded timing chain replacement ran into these arms coming off? Is there any good way to know if there is valve damage without removing the whole head?
I'm wondering how bad this might be, particularly if this means potential valve or piston damage. I've never done this type of engine work before and am not sure how loose those rocker arms should be, but they don't appear to be bolted on or anything. I took off the camshaft and noticed they all fit pretty loose.
My assumption is that those arms are supposed to be loose and as long as the car is in time, the cams are positioned in a way where there is enough force on them to prevent them from coming out. If that's they case, it ought to be good enough to just reposition the arms, get the camshaft back in place, do the timing chain work, and call it a day.
I don't know if this is wishful thinking though. Has anyone doing the dreaded timing chain replacement ran into these arms coming off? Is there any good way to know if there is valve damage without removing the whole head?
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I have the same problem except all the rockers fell out on one camshaft. I searched you tube to no avail. I am under the same assumption that these being non-interference motors and the timing chain very loose caused the rockers to fall. I assume but cannot find any verification that you can replace the rockers. New timing chains and everything's good. Yes, no? I dont know. Any help would be appreciated
I played it more cautious than I needed to and replaced the whole head. In my case, once I had the old head off, I saw it was perfectly fine. All the valves were in good shape, sealed nicely, etc. I still went ahead and put the new one on just to be sure since the job is such a pain in the ass that I didn't want to do it over again, haha!
Do you have a camera scope you could use. You could probably inspect the pistons through the spark plug holes and you could probably inspect the valves through the intake ports. You could also just remove the head and inspect that way. I know it could be risky taking the head off but I think you could get away with it and would then just need to get a new head gasket and head bolts.
I replaced the right head, which was somewhat of a pain. Getting it back in is difficult since I kept the exhaust manifold and cat on the head. It's just an awkward weight distribution trying to angle it in so the head sits on the block guides correctly as well as the cat studs getting in the y pipe holes.
Do you have a camera scope you could use. You could probably inspect the pistons through the spark plug holes and you could probably inspect the valves through the intake ports. You could also just remove the head and inspect that way. I know it could be risky taking the head off but I think you could get away with it and would then just need to get a new head gasket and head bolts.
I replaced the right head, which was somewhat of a pain. Getting it back in is difficult since I kept the exhaust manifold and cat on the head. It's just an awkward weight distribution trying to angle it in so the head sits on the block guides correctly as well as the cat studs getting in the y pipe holes.
Your reply is very helpful. Today I took off the intake and could inspect the valves. They are all open. Metal shavings can be seen on the valve seat. Next step head removal, fingers crossed no scoring or damage to the pistons
Unfortunately I dont know the provenance of this motor. I bought this motor from a salvage yard that said It did leak down tests. Obviously not if the valves are open. So it's been fun. Nothing is worse than getting taken advantage of by a shady "salvage yard". Except having to tear down a motor you paid good money for.
Damm was looking for an answer why the cams shaft side where rockers arm fall off and broke when timming slipped … why they still loose once replaced and there is no ajustements nuts … what I need to do to get them tight?
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