Looks like it - a thicker boss section into the casing - which on it's own would mean a small volume of oil, and crap, would remain in the casing. So slot across, now drains, and still provided enough of a deeper thread to be useful.
- Thread starter RaceDiagnostics
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Usual place to put a thread? Cast sumps, cast gearbox casings, cast diff housings? Perfectly fine for not-often disturbed threads - assuming the right plug/fastener screwed into it with correct torque. Some plugs seal on the taper thread, some seal on the tapers on the base of the plug, some with a washer.Does not help by thread being cut into a casting, some monkey in the past has swung off a ratchet with it having no crush washer to get a seal from the nut face
Do it all the time with our machine design. Would only fit helicoils or similar for repeated tooling changes etc - ie every shift or so. Prevent wear to the aluminium.
We did some tests some years ago - with tapped threads into cast aluminium, 12.9 cap heads would snap before pulling the threads.
Kram
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It looks to have 3 turns of thread left but incomplete turns with the cut through them. What happens if thread fails in action and leaks out?
I think I'd rather helicoil it than simply trust a longer bolt, that sounds like a bodge to me. Coat it in grease before tapping then flush it out well afterwards.
I think I'd rather helicoil it than simply trust a longer bolt, that sounds like a bodge to me. Coat it in grease before tapping then flush it out well afterwards.
That's just a general rule of thumb and while it mostly works, it doesn't always.
You can easily calculate what depth you need for specific threads, sizes and torques in materials - or pick materials to suit the room you've got. Go up in material properties and get good, pretty minimum engagement that is strong enough if needed.
Had issues with a torque arm on a £3m machine slipping where it was clamped with tapped holes into cast iron. Simply couldn't get sufficient clamp with the material thickness, and little room to do much else. Slight re-arrangment of things, some decent steel nut-plates to the rear and some 12.9 cap-head torqued up to full welly, which the cast iron would not take - no more problems.
RaceDiagnostics
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Remember, this has no load, just needs to seal.
RaceDiagnostics
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Well I went for the easy option, I bought a couple of sump plugs from eurocarparts this morning.
The middle one only went in 1 1/2 threads with a washer, the one on the right was too long, but.....not for long.
Trimmed down it went in 3 1/4 turns by hand. Finger test up the hole indicated plenty of clearance. So medium thread locker on the threads and permatex gasket maker on both sides of the washer.
Torqued to 24Nm, gut feel says it will be good.
The middle one only went in 1 1/2 threads with a washer, the one on the right was too long, but.....not for long.
Trimmed down it went in 3 1/4 turns by hand. Finger test up the hole indicated plenty of clearance. So medium thread locker on the threads and permatex gasket maker on both sides of the washer.
Torqued to 24Nm, gut feel says it will be good.
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