aprotogerellis

Hi there,

Time has come to change the waterpump on my 944 turbo and even the thought of removing those bolts makes me shudder. From what I gather there is a huge chance of at least one of the bolts snapping, if not more.

In preparation for this I'm looking to get a helicoil kit... Never having used one before I've got a bunch of questions I'm hoping some kind soul can help with... specifically:

1) In order to helicoil the waterpump bolts, what size of helicoil kit do I need?
2) If the bolts do snap, is it likely that I will have trouble accessing the holes and helicoiling?
3) How long does the process usually take (i.e. helicoiling one bolt)

Many thanks!
Alex

Techno Duck

1) M6x1.0

2) Plenty of space to work if you remove the radiator fans. A right angle drill will be helpful.

3) Entire process takes about 10 minutes or so. Basically drill out or extract the broken stud. Then drill hole (mind the depth!) using the supplied drill bit, use supplied tap, then using the supplied tool thread the insert in.

PorscheDoc

I have never been a fan of helicoils. Much rather use a time-sert (granted in this application you don't need the extra strength as the torque spec is so low). A 6mmx1.0 kit will have everything you need.

Techno Duck

BTW, be sure to wake up the bolts and use liberal amounts of penetrating oil on the nuts / studs. Ive taken off a few waterpumps and never had problems with broken fasteners (two which looked original). I did have that cringe moment followed by the 'tink' and sigh of relief as they broke loose. I have had many problems with stripped threads due to over torqued fasteners from previous installs.

Yummybud924

I ended up breaking one and pretty much stripping all the other ones when removing the rusted bolt.

I ended up helicoiling all of them, not hard to do. it was a real pain getting the broken off bolt out, I basicly had to drive it out then helicoil it. I was pretty nervous as the aluminum block is soft and you can easily damage it. I'm glad I helicoiled them though no chance of stripping them again and don't think I'll break bolts the next water pump change

aprotogerellis

Thanks guys...

About the "plenty of space" to do the operation... I'm working on a 944turbo... so generally have half the free space. Is there enough space even on a turbo?

Hans

Yes.
I am with Doc on this one.
Ever seen the mess left behind when an helicoil came out??