Don't use this truck much but I recall a noise that sounded like a slipping belt. Then realized it was leaking exhaust from a 'missing' manifold bolt/stud at the far front. It's extremely hidden by a bracket so best I could do was reach in with a wire hoping the bolt/stud walked out, not broke. So far, I'd say it's broke. Question is, I would guess I'm not the only one to experience this and wondering if these are usually super stuck, or would a little drilling/extracting work? Pulling that manifold is likely to end in nightmares due to the entire exhaust system coming off, lots will break, etc. Just trying to explore options. Welding a nut won't happen because the break seems flush with the block, and manifold is on there.
Isuzu uses a unique alloy. If you can drill it straight, it should come out. Here, I use Esab Allstate Stud Plus rods, and weld them out. I had a whole fleet of jobsite 300k mile NPR trucks and never had an issue getting manifold bolts out. IIRC, if theyre a stud, they may be different threads on each end.
@heymccall , thanks man! I knew you were all over these NPRs. Because that end bolt/stud is missing, I don't yet know what it was, but the opposite end is a stud, while the rest are bolts. Also has the open slot on manifold, not a hole. Noted on the stud rods! Didn't even know about that! Any chance of a weld recipe without pulling manifold? Honestly hoping gasket is still good and adding some clamping will get this down the road. Probably has 200mi since I noticed the issue. Mostly was noticeable during engine braking so I quit using it for now.
Post some pictures for some comments. Simon C
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