You know whats coming.....

Having blown out the already helicoiled plug for the 5th time I decided it was time to replace the head with the spare I had. Of course, the manifold nuts on the gubbed head came off fine, easy peasy.

the other side, the good side looked very suspect, so I took the chisel to the nut, split it then put a socket on it to wind it off and the F*kker sheared .....GGGGGGRRRRRRRRRRRRRRRRRRRRRRR

I've not had a good look yet, but can I drill all the way thro the offending stud and stick a nut on the back? Is there a more traditional solution? Can I do all of this without removing the head?

Cheers
Gerry

Gerry,
if it's the stud at the front, I 'think' it's possible to use a bolt and nut, although you might have to chip away a small piece of cooling fin.

If it's the one at the back, if an extractor doesn't work, drilling out the stub _very_ carefully then helicoiling M7 or tapping for M8 are the choices.

Ken.

Hi Ken,

it is the front one......Just found a pic in the other forum showing the bolt and nut method....I'll see how the "drilling out" goes first. I did the same on an air cooled Fiat 500 that I restored, drilled out and simply retapped the hole that was left, was still good after 20k The back stud does not look great, but I've yet to try a nut on it......

According to Haynes, I can get the gubbed head off by lifiting the manifold a little.....is this right?

The manifold has to be lifted enough to clear all of (the remaining) studs, I usually lift it clear so it's not in the way when installing the head(s).

Don't forget to be _very_ careful with those pushrod tubes.

Ken

helicoil set and tools at the ready

Ok, so thats everything stripped down and the heads are ready to come off. Of course the barrels want to come as well Should I just pull them both together or is there a clever way of separating the barrel from the head insitu....

Suppose I should decoke while I'm this far in.......

Sean has kindly offered to do the clever bit and I'm more than happy for him to do it !

Cheers
Gerry

I've done the front stud before and replaced it with an M8 stud which went well the way through and had a nut on the underside for extra security. I think I had to shave a bit of fin down or off but I cant remember fully.

If the head to barrel joints are reluctant to let go, it's usually best to remove the heads with barrels attached.
Levering with a screwdriver or flat piece of metal runs the risk of losing a fin from the barrel.
A short length of 2"x2" timber inside the barrel and a mallet can be used to persuade them to separate, but Sean will probably have a more elegant method.

Ken

if a bit 2"x1" is more elegant then yes i do!

Parting tool

DSC00062 by Sean602, on Flickr
split!

DSC00063 by Sean602, on Flickr

Gerry Alan should have followed my advice and copper greased the head/barrel joint and it may be a bit sticky but it should part with perhaps a little help from a screwdriver no loss if you have to resort to timber and a mallet Ill bring the ring compressor

while its all stripped then yes a decoke would be the way to go. That spare head needs the valves out and re ground a set of brass nuts (m7x1), some serrated washers, and a n exhaust stud should be on the shopping list -lambretta scooter shop in town should have em otherwise its Ecas

Okdoke, I'll get the bits ordered up and do the decoke, I. Have a valve spring compressor here, first time using

Cheers
Gerry