Can cylinder block metal be welded in situ?

[ram_doom]

Havent had my CBR600fk long, and the other day decided to change the oil and filter etc. Whilst doing this I noticed that on the right side of the engine (when viewed from a seated position), where the stud goes into the block, the metal had broken away with the stud screwed into it

Hmm, its sealing up alright with one stud holding that downpipe in, but its bugging me. Can it be welded without dismantling the engine, or removing it from the bike? I dont want to replace the cylinder head
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TL1000s, KDX200

[Gradog]

To be honest if it is not blowing I would leave well alone. Trying to weld cast alloy is a pain at any time. The fact that the stud is out means that you would not get any strength out of it without re tapping, and that you would struggle to do in situ.
Keep an eye out for a 2nd hand head going cheap on ebay and hold on to it just in case.
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Grey haired bikers don't get that way from pure luck. Only a biker knows why a dog sticks his head out of the car window.

[Paddy Blake]

I`m not sure where you are talking about but i have a head of a
hornet if that is the same.

[Jubal]

Sounds to risky to me, way too much heat involved with plenty of things around that could be damaged.

You could clean it up well with degreaser and repair the damage with some JB weld, after painting if you do a good job you won't see the repair and it will hold the stud sufficiently to be used.

[ram_doom]

Thanks for advice, I've been a bit concerned about it, but your right, if it isnt causing problems, then its best left alone for now

I'll try and get a pic to show what I mean.

Paddy, I think the motor from the hornet is pretty much the same as the mid 90's CBR6, but mine will be too old (1989). Thanks anyway
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TL1000s, KDX200

[Whosthedaddy]

This happened to me when I tried to remove the headers my exhaust headers. The nut was unsrewing then to my amazement the stud also started coming out as the nut had seized tight .

The nut and stud seemed to screw in nice and tight, so if its not blowing then leave it alone.

It just goes to prove that the old girls dont like being touched too much
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Current : MSX 125 Past : CBR 900RR Monkeybike : c50 LAC : ZXR750 H2 : FZR600 : ZX7R P3 : YW100 : TRX850: Trophy 900 T309 : GSXR 600 L0: Monkeybike : XJ6S Whosthedaddy

[cheekythomas]

It is possible to do it in-situ if careful, they also need to be very good with a TIG set as like has been said, the alloy melts very fast indeed!

The option of JB weld is good, especially on something that age.

[stinkwheel]

JB weld is amazing stuff but I wonder if the heat involved with an exhaust stud is asking a bit much of it.

[Jubal]

500f according to their web site-

https://jbweld.net/products/jbweld.php

[stinkwheel]

[GearboxGeezer]

As a welder ( not very experienced but ive done it for 2 years ) its not really a good idea to weld engine parts whilst still on the bike.. Petrol fumes, oil traces, and all the fancy plastic work is a hazzard for a pretty dangerous situation.

If it ant causeing anything bad to go wrong, then id leave it.

[edd]

JB weld definitely melts on exhaust studs, i stripped a thread on one a while back and tried to secure it with JB weld, it melted with 30 seconds of the bike being fired up.
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Bluespark Automotive - Diesel Tuning for Performance and Economy

[Jubal]

[flame220]

The great motorcycling bodges.
You could get the lug welded in situ if you can find someone willing to MIG alloy (make sure you disconnect the battery first though, I would unplug the igniter, regularor / rectifier & any ECU's before they start though), it could then be ground to shape / drilled & tapped.
Good as new
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What a bunch of cunts on BCF

[Big Pete]

the lug will need to be TIG welded, MIG will just blow it away. the high silicon content in casting alloys makes them run like water when they melt, which is great for casting but tricky to weld. The lump will need to be drained and the pipes removed, along with the stud. Weld up a blob then drill and retap.
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Trust me, I`m an engineer
GarageOfPower.co.uk

[ram_doom]

Some fantastic advice in here, thanks a lot everyone who posted will give everybody karma when I get some. I'm going to leave it be until I have major engine work done. I'm going to print this page for when the time comes
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TL1000s, KDX200

[Jebus]

Hiya, i am a sorta welder, only at college at the moment but i go with GearboxGeezer on this one, you would have to take the engine out or at least strip a lot of the bike away and spend a lot of time degreaseing and cleaning all around the bike, all the electrics would have to be removed and and thing that wont like heat needs to be out of the way. It would have to be tig welded and even then you will need a good welder to do it ally is horriable stuff to weld. Another option you have is to have it brazed on that should be ok reguards to the heat, and far less risk of damage to the engine.

Not sure if this a sutiable solution but it worth a go.

I may of missed the point but cant you drill it out rethread and fit a slighty bigger stud?
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2nd time around CBT: 8/9/11
125 Varadero

[sickpup]

[flame220]

The surface of the ally needs to be ground back to virgin metal before attempting to build it up because ally oxidises almost immediately it comes into contact with air.
I would be prepared to have a go at MIG'ing it ... come to that I have gas welded ally in the dim & distant past ( am I really that old? )
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What a bunch of cunts on BCF