It was all going so well

[Dan Gurney]

So I've been attempting the replacement of the top-mounts on my 85AET Yam 2 troke... And until today it was all going quite well. Got the powerhead off with only one sheared bolt, and since it was already pretty much out of the threaded part when it sheared that seemed to be reasonably good going.

Today I tried to get the clamp at the top of the leg which hold the mounts in place off, and all three bolts sheared like they were made of creamcheese:


I've also managed to shear one of the bolts of the lower mounting clamp:


So I'm looking for an engineering shop or someone with a pillar drill, in West Yorkshire, or at least 'the North' who can drill these out and fix the threads for me. Any ideas? The leg is off the boat right now so I can take it to wherever it needs to go.

Cheers.

[mick]

Might sound strange but Ripon farm services or wharfdale tractors have some handy engineers

[Barrowboy]

Originally Posted by Clamchowder

So I've been attempting the replacement of the top-mounts on my 85AET Yam 2 troke... And until today it was all going quite well. Got the powerhead off with only one sheared bolt, and since it was already pretty much out of the threaded part when it sheared that seemed to be reasonably good going.

Today I tried to get the clamp at the top of the leg which hold the mounts in place off, and all three bolts sheared like they were made of creamcheese:
Attachment 101275

I've also managed to shear one of the bolts of the lower mounting clamp:
Attachment 101276

So I'm looking for an engineering shop or someone with a pillar drill, in West Yorkshire, or at least 'the North' who can drill these out and fix the threads for me. Any ideas? The leg is off the boat right now so I can take it to wherever it needs to go.

Cheers.

I feel your pain...

[camelgas]

If theres no "stub" of bolt left poking up to weld a nut to......... I would be looking for someone with a bridgeport or similar large milling machine. Machine shop job I suspect.

[Festinghouse]

try welding first - great big nut, very carefully make sure the weld gets onto whats left of the bolt then completely fill with weld, allow to cool - this allows heat to travel down to where its seized which then frees it off. i personally have around a 80% success rate with this method. i do this first as the threads dont get damaged, i just clean them out with a tap.

[A1an]

I don't think I've ever managed to get those top clamp bolts out without shearing one or several of them.

I would definitely try pool welding a nut on top first.

[Dan Gurney]

Okey doke, but I'm going to need someone to do that for me too, since I don't know how to weld. The ones on either end have a bit sticking up, but the centre one is recessed.

[mick]

There is a chap in Elland that's Sh!!! hot at that sort of thing

[Ribochet]

Originally Posted by Clamchowder

Okey doke, but I'm going to need someone to do that for me too, since I don't know how to weld. The ones on either end have a bit sticking up, but the centre one is recessed.

Originally Posted by mick

There is a chap in Elland that's Sh!!! hot at that sort of thing

Listen to Mick

[Dan Gurney]

Originally Posted by mick

There is a chap in Elland that's Sh!!! hot at that sort of thing

Got any contact details?

[mick]

Originally Posted by clamchowder

got any contact details?

[Dan Gurney]

Originally Posted by mick

Attachment 101279

Bonzah! I'll call him tomorrow. Cheers Mick.

[mick]

Originally Posted by Clamchowder

Bonzah! I'll call him tomorrow. Cheers Mick.

Pm sent

[jeffstevens763@g]

Dan

any descent engine over haulers will be able to sort that out the threads will be helli coils tapped into the Ali cast i suspect. i spent a lot of time years ago working on Coventry climax engines all Ali block and head [hillman imp] threads went regular.

good luck

regards jeff

[Peter_C]

Looks like one has enough of a head on it to get a pair of locking pliers on it. Smack it with a hammer a bunch, soaking it with a penetrating oil, and you might be able to get it out without heat. The smacking with a hammer "can" break the corrosion up enough to free it.

For the future, now that you know the feeling of when a bolt is going to break, stop and try smacking it, penetrating oil for a couple of days if needed, and heat before breaking them. It is far easy to deal with.

FWIW a good cobalt drill bit will drill stainless. Start small and work up bigger to stay on center.

[paintman]

If you're going to have to get some done by an engineering workshop I'd suggest you let them do them all. Not worth risking more damage.

[Dan Gurney]

Originally Posted by paintman

If you're going to have to get some done by an engineering workshop I'd suggest you let them do them all. Not worth risking more damage.

My thoughts exactly.

[beamishken]

Totally agree if your getting one bolt out at a machine shop might as well let them do them all

Lots of people think they know what to do but this is totally the wrong way to drill stainless:-

Originally Posted by Peter_C

FWIW a good cobalt drill bit will drill stainless. Start small and work up bigger to stay on center.

Drilling stainless you go for a small pilot drill then straight to the core dia of the thread.slow rpm & plenty pressure & lube ,doing it in stages you are asking for trouble either work hardening the bolt or snapping a drill in the hole
A good normal hss drill bit is perfectly adequate for stainless

[Peter_C]

Originally Posted by beamishken

Drilling stainless you go for a small pilot drill then straight to the core dia of the thread.

Since we said the same thing in different wording that means we agree on something

[beamishken]

Originally Posted by Peter_C

Since we said the same thing in different wording that means we agree on something

Your post read as if you work up in small steps but that is not the way when drilling stainless quite a common misconception