Crucifix oil leak + search for exhaust manifold
#12
You don’t need cobalt bits, what you need is a good center punch and a steady hand. You will also need to take the manifolds off of the engine where are you can do this on a bench. Well, you don’t need to but your success rate goes through the roof comparatively. The broken bolts are relatively soft and easy to drill through with a sharp bit. I’m assuming broken bolts are your problem. If there’s anything sticking out then you may be able to soak it and then heat it with a torch to break it free and spin it out with vice-grips. I was lucky and got all my broken ones out this way. If not, the way to achieve the most predictable outcome is to take a grinder with a cut off wheel and remove as much of the broken stud as possible. You want a nice flat surface on which to place the center punch.
Punch it as close to the center as you possibly can and then use a 1/8” drill bit to drill a small hole through the exact center of the broken bolt, using lots of PB blaster or equivalent while you’re doing this. If you’re really lucky, the bolt will spin out the backside of the manifold as you’re drilling through it. Since this is a pretty rare occurrence, the next step is to get a slightly larger drill bit, maybe 3/16ths and enlarge the hole further, again using lots of penetrating fluid.
You can try your luck with a screw extractor and try to reverse out the broken piece but if heat and vice-grips didn’t get it to budge a screw extractor probably won’t either. Next you can drill it out to 17/64ths and try to chase the threads with an M8 x 1.25 tap. At this point the only thing left in the hole will be the little rings of thread from the old bolt. With any luck your tap will chase those and you’ll end up cleaning up the original threads in the manifold. this is where a very steady hand is critical. Or you can skip this and drill it out with a 5/16” drill bit and tap the hole for a 3/8-16 bolt, which is just larger than the original stud that was in there.
Oh, search here for crucifix seals. There are two types and the larger style seem to be the ones you want. It’s been discussed here recently. There are two seals in your engine.
Punch it as close to the center as you possibly can and then use a 1/8” drill bit to drill a small hole through the exact center of the broken bolt, using lots of PB blaster or equivalent while you’re doing this. If you’re really lucky, the bolt will spin out the backside of the manifold as you’re drilling through it. Since this is a pretty rare occurrence, the next step is to get a slightly larger drill bit, maybe 3/16ths and enlarge the hole further, again using lots of penetrating fluid.
You can try your luck with a screw extractor and try to reverse out the broken piece but if heat and vice-grips didn’t get it to budge a screw extractor probably won’t either. Next you can drill it out to 17/64ths and try to chase the threads with an M8 x 1.25 tap. At this point the only thing left in the hole will be the little rings of thread from the old bolt. With any luck your tap will chase those and you’ll end up cleaning up the original threads in the manifold. this is where a very steady hand is critical. Or you can skip this and drill it out with a 5/16” drill bit and tap the hole for a 3/8-16 bolt, which is just larger than the original stud that was in there.
Oh, search here for crucifix seals. There are two types and the larger style seem to be the ones you want. It’s been discussed here recently. There are two seals in your engine.
#13
#14
Awesome write-up! Really appreciate it! Do you have a source for the bearmach parts in the US? Ordering from their website is about $20 in shipping + parts. Looks to be the only one still selling that style so I'll get them worst case, but just curious if they are here already and I can skip the shipping.
Edit: Just saw your post from their website, I'll assume that's the only place to get them. I'll get them on order! Thanks!
Edit: Just saw your post from their website, I'll assume that's the only place to get them. I'll get them on order! Thanks!
Ukar auto sells them on eBay, I've bought from them before, good seller.
Rhys L.
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Sixpack577 (04-03-2020)
#15
I would heat up the manifold(propane torch will do)
and use a big hammer and center punch on it, try hitting at an angle to "unthread" it.
Give the threads a shock under heat, and keep adding penatrating oil.
It sounds like the studs on the other end of the Y pipe to the muffler. No way would it drill out on mine, only they are pressed in, not threaded.
and use a big hammer and center punch on it, try hitting at an angle to "unthread" it.
Give the threads a shock under heat, and keep adding penatrating oil.
It sounds like the studs on the other end of the Y pipe to the muffler. No way would it drill out on mine, only they are pressed in, not threaded.
#16
Okay so I’ve had this on the bench in a vice trying to drill out this one last bolt. Everything else is drilled and tapped except this one. I’ve tried everything from pilot holes and cobalt bits(6 of them). High speed, low speed, oil, no oil, grinders. Nothing will cut through this stud!! Anyone have any ideas? They’re Milwaukee bits and they ain’t cheap. Only other thing I can think of is finding someone with an oxyacetylene torch and blasting out, then filling in with a welder and drilling that
The following users liked this post:
Sixpack577 (04-03-2020)
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