Xt600 manifold stub broken in head

[Ryder666]

Having a bit of a nightmare trying to remove a broken manifold stub in a mates 1988 xt 600, bike has sat in a lean-to for a number of years and the left hand manifold stub has corrosion welded itself into the head, have tried heat and penetrating oil, cold chisels and welded a pipe to it and tried to knock it free, no joy as yet.

Suggestions please guys

Tom

[Bhud]

Can you remove the head, get it on the table and blast the remains of the exhaust header with more weld?
With a high enough voltage, i.e. doing it wrong, it should blow right through the steel, right? If it blows through in one or 2 places, the molten steel should pool, and when it cools down you'll be able to wedge a screwdriver in there and lever it out.

Of course, you wouldn't try this without being aware you could destroy the head. From my pov, if were mine, then as it's not going anywhere right now anyway, and it's a project bike, I could up the risk of damage. However, your appetite for risk may differ.

Worse comes to the worst, you'll end up either taking the head to a machine shop or searching for a replacement on Ebay. Also, if you do try this act of desperation and it works, check for signs of warping before refitting the head.

There may be other and better ways to approach this problem. I'm only saying what I would do - not suggesting you should do this, etc.

[Pete.]

Several way of attacking that. First things first make sure the valve is shut and stuff some protection down there if you can.

You could do as Bhud says and wind your welder up to 11 and burn the rusty collar out by running a line of weld down one side.

Or you could hit it with a carbide burr in a die grinder or at a push, a dremel.

You could clean up the inside a bit to get the rust off then run a ring of weld around the inside. That will shrink the collar and break the bond

If you have neither an air chisel or even a small sds breaker with a sharp chisel to cave in one side wich should break the bond and loosen the collar.

Once you have the piece out, remove the spark plug and blow compressd air into the chamber then turn the engine over until the exhaust valve opens. That'll blow any debris out instead of letting it fall in.
____________________
a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[steve the grease]

You'll get that out, just keep tapping it , more wd40, more tapping . Eventually the rust seal will crumble and it will pretty much drop out. Patience . Or a burr......
____________________
All the above is my personal opinion, you can see my lips move, but I'm talking out of my arse.
I've been riding, and fixing , bikes for 50 years, in that time the more I learn, the less I am absolutely sure of.....

[stinkwheel]

Looking at the picture, there isn't NEARLY enough penetrating oil floating about to do anything useful. I use ATF mixed 50:50 with paraffin or acetone (the latter if there are no rubber or plastic bits nearby).

As above, If you can burr/saw through it in one point, it should collapse in with the application of some percussive maintainance
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[jeffyjeff]

Use a welder (standard stick electrode, not MIG or TIG). Don't crank up the voltage, don't try to blast through the stub. Run one or two beads along the length of the stub. As the weld cools, it will shrink the stub, reducing its outside diameter. Removal should be relatively easy after that. We used this technique to remove stuck cylinder liners (back in the day when overhauling diesel engines was a cost effective option).
____________________
History shows again and again how nature points out the folly of men - BOC

[sickpup]

[Pete.]

Tig would be the better of the three if you had it. Big heat input and no splatter.
____________________
a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[jeffyjeff]

[Bhud]

If you try to lay a bead down using a stick welder on 1mm- or 1.5mm-thick steel as shown, you'll blow a hole in it. Blowing a hole in it was in fact my initial suggestion, but it doesn't make any sense you would suggest using a stick electrode and an arc welder to lay a bead down the length of that 1mm-thick steel. If you could do that on 1mm-thick steel, I'd love to see it.

[colink98]

seems to be a few used heads for sale on the bay for £100
i suppose it depends how much effort you want to put in to rescuing the current unit ?
____________________
PCX125 (stolen) - CBF600 (current)
Ride it like you stole it.
ride sensible and not like an idiot and you wont get 6 points in one week.

[Ryder666]

Lots of fluid has been used but had been burnt off, biggest problem is the collar is 3.5/4mm thick and the tools available are not big enough/man enough to touch it and I only have a little 125amp hobby welder that just can't get enough heat into it, next attack is going to be a carbide burr to try and relive enough material to then be able to collapse it with a cold chisel. The hope is to not have to remove the head as the engine was rebuilt not long before being laid up ( with receipts to prove). Me and my mate will beat it just slowly trying not to destroy the head on an otherwise tide £400 project bike

Tom

[Pete.]

[stinkwheel]