Copying the contents from Broken clutch master hydraulic fitting - LS1TECH - Camaro and Firebird Forum Discussion

At home
Noise 1

At shop. Sounds like B2 rocker arm. TSP CHE rockers, Manton pushrods, Johnson lifters. Will wait for it to cool and pull cover. No misfires, though.
Noise 2

Removed valve cover. I stuck an endoscope around the valve train area and don't yet see the missing bolt. There is a pool of undrained oil at the rear, but couldn't feel anything in it. Is the bolt small enough to make its way to the oil pan without damage?
Where's the #4 rocker stud?

Witness marks (center left) on underside of valve cover, compared to new spare on right. Jordan at TSP said there's not enough room under the cover for the bolt to come out of the hole with cover installed. All bolts were tight during removal, one ignition wire wasn't pushed on all the way to a coil. No misfire on cluster. I needed to use a pick to separate the cover from the head. Looks like original GM gasket that came with cover. I can't think of any time I've had this cover off since I upgraded covers for better pcv a few years ago, nor from a shop. I didn't hear anything metal bounce down the outside of the engine, nothing on the floor. Felt around inside head couldn't feel any bolt, nor did I locate it with an endoscope. Jordan also said the bolt would have to navigate past a lot of moving parts to reach the oil pan.

Jordan sending me a replacement bolt. I can easily pop on new bolt & cover. But how do I give myself peace of mind on possible hidden damage? How much of that pcv shield metal went elsewhere?

 

I don't think the whole bolt is likely to be able to get through a drainback hole. It's about 1½ - 2" long. Would have to make too many twists and turns to get past everything. Might be possible, but not likely. I'd pull all the rockers, and the stand things, off of that head, and see if the bolt is trapped underneath something somehow.

I'd be more inclined to suspect the bolt broke off, if it's truly missing. Smaller pieces like that would have a better chance of escaping. Is the bolt hole in the head completely free of bolt (not "stud") fragments?

If the whole bolt is missing, then either it backed off, or the threads pulled out. Be sure you figure out what happened and why before just slapping it back together and the same thing happens again. If the threads pulled out you'll have to repair the hole, just putting another bolt in won't work. A Heli-Coil works fine for that. I'd recommend Heli-Coiling them ALL if that one needs it; after all, if someone at some point in the deep past overtightened the bolts and damaged the threads, there could be 15 other possible land mines in there for you to step on.

I wouldn't worry too much about debris from the PCV baffle. Looks like most of it is all still there, if a little worse for wear. No reason to replace the valve cover unless you just want to for whyever.

Be aware that if the heads have had any port work, there's a good chance that the intake rocker bolt holes are now exposed to the ports. This will cause a large mystery embarrassing source of oil smoke. Use thread sealer on the bolts. NOT silicone, as it dissolves in gasoline. Use the Permatex / Loctite stuff with PTFE and let it set up for a day or 2 before running it, if possible.

 

I bought the block & heads back around 2009, I'm not aware that they've ever had any port work, certainly not requested by me, only milling. I stuck the endoscope down the bolt hole but it was blurry, I'll try again. This PS cover has a vertical PCV tube up front, I was thinking that the vertical position might help with gravity trying to keep oil mist where it shouldn't be. I have a new version with the horizontal tube as well. It seems airflow is entering the cover and not exiting, so I'm fine swapping to the new cover to clean up the engine bay.

 

Just pull the covers and do a thorough inspection. If there's no sign of the bolt, and IF it did break off, find the most powerful, small diameter magnet you can, and carefully probe the oil drainbacks. If you have pooling at one of the holes, I'd suspect the bolt to be in that drainback somewhere. Hope this helps.....

 

Boroscope might be helpful here too.

 

Bolt snapped, I believe the head is in the second-from-rear oil drain back next to inside head bolt, and the remainder needs to be extracted from the head. I'm having trouble getting my straight telesoping magnets to grab the bolt head. Do they make a more flexible option for me to try to grab it? Can I safely extract the remaining bolt from the threads without removing the head? The magnet needs to be small enough to reach between the head bolt and edge of drain.

Loose bolt head in top center.

bolt snapped inside head.

 

That's pretty much kinda what I was telling you to expect to find.

Before getting too wound up about the piece of the bolt in the drainback hole, see if you can get the remains out of the bolt hole. If you can't, the head's coming off ANYWAY. No sense dinking around endlessly with something that ultimately might not matter at all.

Priorities.

 

The dedicated GM/LS performance shops have mostly left the area. There are normal shops that can install engines and connect harnesses, one that's good but a very small (preferred if possible) shop and booked out for a long time, and another small shop that's absolutely full of himself. I'm in an apartment so I'll need to search around. We used head studs on the engine stand, how much of a PITA is that to attempt to remove heads over head studs with engine installed? I'm not against starting over on the long block due to excess blowby. Less things for a non-performance shop to screw up with an assembled longblock.

 

Fairly severe.

Most likely if you need to pull it you'll need to back the studs out but leave them sitting in the head, and pull them along with the head. Pay attention to which ones need that so you can do the same putting the head back.

 

Make sure you remove the hardened flat washers on the studs BEFORE pulling the heads. Because if you leave them and tilt the head only slightly when removing it, the washers can slide out and fall wherever. A bad wherever would be into the engine internals!! So I remove them with a couple of small diameter magnets. One magnet MAY work, but it may tilt the washer and bind it on the stud. Better to use 2 magnets, roughly 180° apart on each side of the stud, to evenly pull the washer up and out......

 

Harbor Freight make a bendable magnet reacher thing.

 

The broken bolt is 6mm below the surface, not under the cowl but difficult to get a tall tool in there to attempt to remove it. I picked up the Harbor Freight flex magnet, but the head is too big to fit in the area and the light is spastic. I have to keep digging for which ARP head stud kit I bought, I presume it was 234-4317, but they have other varieties with different torquing sequence. Anything wrong with removing that single stud nut, carefully removing the nut & washer with a magnet, removing broken bolt, then re-installing the nutt with the correct torque sequence? The 234-4317 says three passes (25,50,70) but since all the other studs are installed, can I go straight to 70, following the remainder of the clean/lube instructions of course?

Assuming I have space, how about this option? Relevant portion starting at 1:48.

 

If you have head studs, then you don't have "bolts" there. You have studs threaded into the block, then nuts & washers holding the head down. Not like the rockers which of course are bolts regardless.

Yes you can remove one nut and re-tighten, if that gets you clearance to reach the loose piece of rocker bolt. Yes you would go straight to the full torque if only doing one whie the others are still fully tight. The reason for the gradual torquing is so that all the hardwares get tightened evenly, rather than one all the way tight and the others not, which would risk warping the head. The exact numbers aren't as important, as simply assuring that all of them compress the gasket about the same as they tighten up. But with just one being loosened and re-tightened, that's not an issue.

 

Man, that bolt must've been defective. Sorry to hear this happened. IIRC, and I think I do, aren't the OEM rocker bolts all 12.9 bolts? You'd think the 12.9 bolt (or even a 10.9!) would strip the aluminum or break off a chunk of the head casting before the elastic limit was exceeded......

 

Engine assembled in 2019, and suddenly breaks bolt? Very weird. These are not oem bolts, they are allen-head bolts TSP provides with their CHE/OEM rockers. I don't know if I still have the oem bolts.

 

They should have a strength code/number up on the bolt heads, usually stamped radially around the head. Hopefully they're at minimum 10.9, and probably are 12.9. Those usually are some mighty strong bolts.....

 

New vs removed bolt, length difference ~11mm. These metal 'threads' came out of the top of the bolt boss, could these be part of a helicoil repair? Remainder of bolt is ~4.7mm down the hole. Both bolts are 12.9 grade. Should I install the new replacements, or look for OEM bolts?

 

Doesn't look like a HeliCoil to me. Doesn't look anywhere near thick enough.

HCs are a type of stainless. What's that made out of?

 

Not sure, it's like a tiny slinky, you can gently expand it and upon release it returns to normal shape. 25lb magnet just barely picks it up before it falls off.

 

If you drill it out - go get one of the drill bits that are in reverse to cut/drill stuff. You might get lucky and it snags it / or loosens it when you are drilling it. I would also check all the other bolts to see if you have other mismatch of parts there. The one with the longer shoulder could have been bottoming out on the threads.