Sump plug thread, Repair of sump thread Options

[Desperado]

Hi.

Has anyone used a thread repair kit which repairs the thread in-situ? If so, which one and how did it work?

I'm trying to avoid having to remove the sump and i'd like to know if I'm better off doing that anyway.

There are a few that I've seen which re-tap the hole without drilling, simply tapping the damaged thread with a larger size and fitting a larger plug. This seems to rely on running a tap into the damaged thread which cleans out the damage and cutting a new thread. All straight forward really and ive repaired them before, just never on the car!

If anyone has any experience of these i'd appreciate your thoughts.


Desperado.

[Cloverleaf76]

Hi.

Has anyone used a thread repair kit which repairs the thread in-situ? If so, which one and how did it work?

I'm trying to avoid having to remove the sump and i'd like to know if I'm better off doing that anyway.

There are a few that I've seen which re-tap the hole without drilling, simply tapping the damaged thread with a larger size and fitting a larger plug. This seems to rely on running a tap into the damaged thread which cleans out the damage and cutting a new thread. All straight forward really and ive repaired them before, just never on the car!

If anyone has any experience of these i'd appreciate your thoughts.
Desperado.

I've used a helicoil (actually VCoil) a few times and it has been fantastic from a repair point of view. Not a drop of leakage, and it will take a sensible torque as opposed to being afraid of doing it up in case it threads.

There are massive downsides though.

Firstly, as a blind hole into a void you have no way of getting any swarf out. Obviously the strainer should filter it out on it's way into the engine, but still.

Second, the new spring if wound in too far acts as a strainer, preventing any solids in the oilpan from ever leaving via the drain hole.

This combination of side effects used to keep me up at night, because then any oil change thereafter is incomplete. If you're clever and can think of a way of doing it you could cut the coil to length first and that would fix it. However, that is a lot easier said than done...

[Desperado]

Agreed Re Heli-coils or vee coils.

I'm tempted towards retapping the hole to see what I'm left with first.
or, making a boss and retapping the hole bigger and threadlocking the boss in so that I can use the original plug. Ive seen some kits for this but only available in the US
I found a tapered plug that is supposed to be a repair method - you just wind it in and it the large end of the taper seals it - doesnt appeal to me really, I'd be dreading the next oil change.
Or the kit i mentioned in the original post but the suppliers dont know anything about it....

[Cloverleaf76]

Agreed Re Heli-coils or vee coils.

I'm tempted towards retapping the hole to see what I'm left with first.
or, making a boss and retapping the hole bigger and threadlocking the boss in so that I can use the original plug. Ive seen some kits for this but only available in the US
I found a tapered plug that is supposed to be a repair method - you just wind it in and it the large end of the taper seals it - doesnt appeal to me really, I'd be dreading the next oil change.
Or the kit i mentioned in the original post but the suppliers dont know anything about it....

If you don't wanna drill, then just an ordinary tap would do as long as it is slightly larger than the hole. You're still gonna have issues with metal getting into the sump, though. You're also going to be back at square one with yet more threads made of super soft aluminum and ready to ruin your weekend.

I'd be careful too with tapered plugs: too tight and you could shatter the sump.

If I ever had to do this again on a twinny I think I'd drill and coil, but make sure I cut the coil to length first without distorting it. Maybe with a disc cutter, because snips inevitably distort it and make it harder to fit.

I'd be sure to use a new crush washer too!

[Desperado]

If you don't wanna drill, then just an ordinary tap would do as long as it is slightly larger than the hole. You're still gonna have issues with metal getting into the sump, though. You're also going to be back at square one with yet more threads made of super soft aluminum and ready to ruin your weekend.

I'd be careful too with tapered plugs: too tight and you could shatter the sump.

If I ever had to do this again on a twinny I think I'd drill and coil, but make sure I cut the coil to length first without distorting it. Maybe with a disc cutter, because snips inevitably distort it and make it harder to fit.

I'd be sure to use a new crush washer too!

I'm going with this. The M22 one, I hope it its what I think it is...

http://www.astatools.tw/product/m13-m15-m17-m20-m22/

The car is leaking both Oil and coolant at the moment, I cant keep up with it New thermostat on order, I've rewired the BBoB, The power steering pump has been replaced and now thats making a noise.