jchapura

Wow, that is a pisser. You've had such bad luck with this job. Very sorry for you...

Helicoil versus...

To minimize removing metal, would it be possible to go up a size but English rather than a metric next full size? If you do just drill and tap, be sure you have a regular tap and a "bottom" tap (for blind holes).

Helicoil will definitely work but it removes more metal and then there's seating the coil, etc.

The aluminum should make it easier.

ALEV8

Crapola! I tried one of the better looking fasteners from before but no dice. Hooked up my Schwaben airlift and system won't hold vacuum. Indeed at square one again. Option one tap it. Option two helicoil it. Option 3 send it to the Indie. Option four Porsche to the rescue.

Head scratching!

Petza914

I have AirLift also and couldn't get it to even collapse the rubber hoses on either of my 997s, yet neither leak or use coolant. Maybe there's a hose that has to be clamped off somewhere as part of the overflow reservoir or something, but just because your AirLift won't hold vacuum, I wouldn't say that you're necessarily in trouble.

A helicoil is going to require a fairly large hole in a wall that doesn't look like it has that much material to spare. I would try to tap it to only the next size up whether that's a metric or a standard one so you remove the least amount of material as possible.

ALEV8

****!!!!

Saaboteur

Sorry to hear about your troubles. Could be worse though - you could have broken the whole bolt in the housing itself.

I would try to 'chase' the thread with a tap first, but sounds like you may have done that already? Idea being that it could clean up the threads sufficiently to allow a normal bolt to go in. Otherwise, I like the idea of helicoiling the same metric size.

ALEV8

I did chase the threads with a "cleaner" tap set.
I have tap and dies set to chase threads clean and some taps and T handles.
Need to match the size M6 x 1.?
Use a bottom tap?
Tap and install next size up bolt sounds do-able.

Does anyone know the thread pitch off hand?

ALEV8

6x1.25 helicoil is the go. M6X1.25X20 helicoil helical
Thread insert fine metric. I guess it's time to grab your nuts fellas!

ALEV8

OTOH Jchapura's idea may work without as much collateral damage. I will add that a wise, veteran machinist and former race car builder and Baja 1000 bike racer said HELICOIL without hesitation. I trust his relationship with metal over the years.

Saaboteur

Another vote for helicoiling! Done right I don't think you'll have any issues, and you can keep it all stock bolt sizes.

user 72902

That's weird because I switched to Evan's Waterless Coolant and then back to regular coolant and I've drained my system a bunch of times. I have an AirLift and it for sure collapses the hoses but there was not anything to pinch off. Pete did you pull any vaccumm even though the hoses didn't collapse?

Petza914

Nope, got nothing. On my car I thought it might be because of the 3rd radiator and the pump for it that's part of the RUF kit, but that's still s closed system. But my wife's is stock and nothing on that one either. Maybe my AirLift isn't any good.

jchapura

As I thought more about my "English" suggestion, I came up with another idea - to minimize the amount of "meat" you remove from the block for the enlarged bolt hole, why not just go down in size for the bolt (and still helicoil)? The application only needs 7.5 ft-lbs. I'm sure it could be looked-up whether an M5 or M4 in aluminum can support that. And put a washer under the bolt head...

Or, buy a lifetime warranty tstat and weld the housing cover to the block. Just kidding. Or lots of RTV...

ALEV8

Dropped at Porsche a minute ago. They are going to also put my Michelin Super Sports on and align/balance.......and check the frunk for any ghosts. I did make off with hardback copies of the GT3RS book in the waiting area!

Helical is what they said as well, and hopefully not too long of a stay there BUT so much fun. When I go back they want to trot me back there to the tech working on it.

ALEV8

Word from Porsche is there was no need for an insert! They are calling me back shortly. Cooling system should be serviced plus the wheels and tires mounted and balanced and alignment. I'm having them also adjust pass door and the window that's a hair off. Picking up a Fabspeed CF intake to drop in as well. That should get me back on the road!

Sloppy short shifter dies next!

jchapura

Alex, how can that be? I wonder what could be wrong with the hole?