Head welding

[cribbs74]

All,

Since I aquired my 66 CL77 I have had a problem with a broken exhaust stud. The PO of the bike broke off a head stud flush with the head and decided to drill around the stud to remove it. I went ahead and drilled the stud out properly re threaded and installed a new stud. The problem is since the area around the stud is galled out and useless I was unable to create more than just a few threads for the new stud to thread in to.

I used an expensive high temp exhaust repair compond around the stud once I threaded it in, but it only lasted one season before the stud fell out while riding.

My question is... Is it possible to have the head aluminum welded to fill in the stud hole and the re drill and install a new stud. I assume the head is cast aluminum. I know you can weld cast iron with decent results just not sure about aluminum. I know I could replace the head, but I really don't have a reason to at this time. Thanks for any info you can provide.

[67305dream]

Hi:
The best thing to do is to buy a heilicoil kit. It comes with a drill to enlarge the hole plus a tap to tap it out, an ensersion tool and a coil of threads that screw into the new hole then you can put an excact same size exhaust stud as the original. These are used on aircraft so you know the quality and strength will be sufficient.
Surf around on the web, you'll find them.
This is not only the easiest way to do it but also the best.

[305]

yes, try the heli-coil . i don't know what size the stud is , but i'm sure it's metric . heli-coils are available in metric. if that doesn't work you can have it welded. you will need a tig welder , so it would be best to take it to a pro.

[LOUD MOUSE]

The answers given are right on about the coil repair.
The coil set you need is for a 6X???mm standard metric thread available at most fastener/bolt/screw suppliers.
As you stated the area was drilled around the stud there may not be a lot of aluminum surface for the coil to thread into.
If that is fact and I've had some which had JUST A LITTLE of contact surface and with those I insert the coil, apply J.B. Weld in the threads of the coil and stud and install the stud.
So far never a problem with this sort of repair. ...............lm

All,

Since I aquired my 66 CL77 I have had a problem with a broken exhaust stud. The PO of the bike broke off a head stud flush with the head and decided to drill around the stud to remove it. I went ahead and drilled the stud out properly re threaded and installed a new stud. The problem is since the area around the stud is galled out and useless I was unable to create more than just a few threads for the new stud to thread in to.

I used an expensive high temp exhaust repair compond around the stud once I threaded it in, but it only lasted one season before the stud fell out while riding.

My question is... Is it possible to have the head aluminum welded to fill in the stud hole and the re drill and install a new stud. I assume the head is cast aluminum. I know you can weld cast iron with decent results just not sure about aluminum. I know I could replace the head, but I really don't have a reason to at this time. Thanks for any info you can provide.

[cribbs74]

The answers given are right on about the coil repair.
The coil set you need is for a 6X???mm standard metric thread available at most fastener/bolt/screw suppliers.
As you stated the area was drilled around the stud there may not be a lot of aluminum surface for the coil to thread into.
If that is fact and I've had some which had JUST A LITTLE of contact surface and with those I insert the coil, apply J.B. Weld in the threads of the coil and stud and install the stud.
So far never a problem with this sort of repair. ...............lm


Thanks Guys,

Hey Loud Mouse you are correct in that there was a good bit of material removed from around the stud. I will go ahead and attempt a helicoil. When I initially put the stud in I used JB weld and it didn't hold so I went ahead and bought a more expensive compound that lasted about 6 months. Perhaps with a helicoil the JB weld will hold up better.

On a side note I am headed your way as I received orders to Randolph AFB TX so now I won't have an excuse to not drop by and visit. Thanks for the reply.

Ron

[LOUD MOUSE]

I expect that with the coil the JB will get a good grip.
If not I can put 8mm coil and special stud along with the JB.
Ya are welcome to visit and if ya can bring the head and I'll work on it.
Hopeing to see ya here. .................lm

quote="cribbs74"]

The answers given are right on about the coil repair.
The coil set you need is for a 6X???mm standard metric thread available at most fastener/bolt/screw suppliers.
As you stated the area was drilled around the stud there may not be a lot of aluminum surface for the coil to thread into.
If that is fact and I've had some which had JUST A LITTLE of contact surface and with those I insert the coil, apply J.B. Weld in the threads of the coil and stud and install the stud.
So far never a problem with this sort of repair. ...............lm


Thanks Guys,

Hey Loud Mouse you are correct in that there was a good bit of material removed from around the stud. I will go ahead and attempt a helicoil. When I initially put the stud in I used JB weld and it didn't hold so I went ahead and bought a more expensive compound that lasted about 6 months. Perhaps with a helicoil the JB weld will hold up better.

On a side note I am headed your way as I received orders to Randolph AFB TX so now I won't have an excuse to not drop by and visit. Thanks for the reply.

Ron

[cribbs74]

Thanks for the help Loud Mouse, I will give it a shot on my own first. If that fails I will be sure to swing by your place. I'll be down there in March to sign in to Randolph. I'll be on my own for a bit until my house sells here so I'll be a bachelor for a while......i'll take advantage of that time to get a few things done.