Exhaust manifold stud?

[Cali_bay]

Having replaced the fuel lines on my bus whilst underneath I found that one of the exhaust manifold studs was missing :shock: (might explain the popping in the heat exchanger on overrun that I have had for a while).

I fitted a new M8 stud, but pulls straight out when tightened. Not sure exactly what I need to do with it now :? . Is is best to re-tap with a larger thread size, helicoil or is it a head off job to fix?

Thanks,

Si

 

[Milky]

Hi, careful on this as my type 4 engine Bay has studs that are M8 at one end and M9 at the other.I am unsure whats a type 1 engine has fitted .I have some type 4 studs if you get stuck.Difficult to get and expensive new [£4.50]

 

[Cali_bay]

Ah, my engine is a type 4 1700, so that could well explain it :roll: . I'll drop you a PM if I can't get hold of the bit.

M9 is not a standard common thread size though :shock: :?:

Thanks,

Si

 

[HairyYeti]

The last 1700 I had had M8 studs (both ends). Chances are yours were M8 too but the Aluminium has stripped in the head.

Helicoiling is a good option - or if there is eough meat lef in the stud-holes threads tap out to M9.

My 1800 heads have M9 into the head and M8 for the nut to hold the heat-exchanger/downpipes on.

Stateside tuning sell M9/M8 studs. So do VW Heritage. Both are 8:8 regular steel.

We may commission a batch to be made in Stainless Steel if we can find a thread-rolling company that can do M9..!

 

[noddy]

Just watch out for swarf in the cylinder head one you have re-tapped to M9.

Hellicoil kit are pricey, contain a unique tap to over size the old thread to take the coil, a kit with about 10 coils cost around £35.

A cheep tap kit should only set you back about £20.

 

[67 BAY]

Have got some bolts which fasten rocker gear on type 1 engine.Gave a mate some to repair his 1800 engine and said they worked. Got some more if you want some.Will try and get a pic tomorrow.


Steve

 

[Cali_bay]

Thanks for your help guys.....manged to track an M9/M8 stud down (not one for the local motor factors :? ), just need to get some time to give it a go.