Welding broken engine mounts

[Rocinante]

My bike´s been running for ten years with cracks in the rear lower engine mounts, repaired in Chile by a Austrian tool mechanic who used brackets and a magic two component whatever to strengthen the mounts.

However, a close inspection reveals a new crack since the last inspection. The crack is on the lower side of the mounts and with the old cracks on the upper side, I suspect I´m running out of hold.

So today I contacted a aluminum specialist in the area who claims he can weld them, but said it needed to be stripped as far as possible, because the more heat he can use the better the weld. I´m visiting him tomorrow for an inspection. If I go ahead, I will need, obviously, to remove the engine from the frame.

Anyone who can share some light on this? I know it´s not a common problem, but for Rocinante it has happened twice. The first time was in San Diego on our way south and Triumph replaced the upper and lower crank case under warranty.

Should I be skeptical to welding, or is it a piece of cake for an expert (this guy has a very good reputation for being just that)?

[BruKen]

Engine case mounts or frame mounts?  Welding is not an issue, but if its the engine case the age and oil contaminants that will have leeched into the magnesium alloy will result in a poorer weld. There is no real way round that no matter how thoroughly its chemically cleaned. That's not to say the weld won't be strong enough, but it takes a bloody good welder. I can weld ali, its a cinch, provided I've thoroughly cleaned the joints, and I do mean thoroughly. Otherwise I'm crap. Think silicon and spray paint, you get the idea.

[Mustang]

I assume it's the mounting lugs on the engine ?

why not just get a replacement engine there are lots of them out there ......
tridents, sprints ,tigers ,early speed triples , trophys

[Rocinante]

It´s the engine case mounts. Otherwise it would be straight forward as you say, Bruken. He is a bloody good welder, so there´s hope.

Why not a replacement engine, Mustang? Well, here I am back at that same old question:). Last time was when I bought a used cylinder head, and so far the reasons are the same, price and nostalgia. Sensible? Not, I guess... :? The engine burns oil now and has covered about 150Kkm.

If it´s going to be too difficult/expensive/labour extensive to fix or if I just feel stupid repairing that dying engine again and again, I´ll order a rebuilt engine from Triumph-Ant in the UK. They can deliver in three weeks for the moment (guess the short delivery time could have to do with the current recession) for about 1200 UKP plus 25%VAT, delivered on my door. I´ll consider it over the weekend after seeing the welder.

On the picture you see the right hand side mount, seen from behind. The yellow spring belongs to the shock absorber.

The rust colored bracket and the green stuff is the repair we did 11 years ago(the green compound may actually have helped keep the fracture clean, Bruken). The bracket has been clamped around the flat frame leg and point welded to the frame to keep it from being shaken downwards, but with as little impact on the frame as possible.

The red arrows point to where the cracks are. The old one are the one on top, while the new is below. It´s not actually on the image because the new crack is on the left side (harder to photograph due to the drive chain. But it´s visible and about 1-1,5mm wide, just about where the arrow is.

[Rocinante]

Btw, how much work is it to remove the engine? From what I´ve read in the handbook, it seems relatively straight forward.

[BruKen]

Getting it out is easy enough, getting it back in is really a two man job because its not a straight lift, though it can be done if you have a second jack reasonably safely on your own. It's a bit a a wiggle though, I only crunched my fingers 3 times  :lol:


edit:  I cant say I'm familiar with every tiger model out there ... just my own 98, but that repair job looks suspect and that engine mounting system on the frame.... is positively a heathrobinson affair (so it may very well be an original hinkley job, but I doubt it) and could well be why your casing mounts keep cracking. If you are going in for repairs, dont repair an emergency RTW  "get me back on the road asap" botch job, return it to original or you could be facing the same problem in the future.
And not wanting to pour salt into the wound but the engine is integral to the frame rigidity and as the engine here is not firmly attached to the frame where it should be, and hasnt been for quite some time, I'd be looking for stress fractures along the spine and subframe too. Hopefully Mustang comes and corrects me, but that's bloody awful.

[BruKen]

BTW, it's a whole lot easier attatching the frame to the engine than lifting the engine into the frame. But you'd need a complete strip then.

[Mustang]

Myself .................drop that lump and put it on a shelf for nostalgia purposes .

New lump from Triumph-ant in its place .

All of your problems solved , bike is like new again.

It's not like they came with matching #'s like in days of old .

remove carbs remove exhaust unplug electrical connectors remove foot peg brackets ,pull out the other 4 engine bolts . don't be suprised if the lump is still hanging in the frame at this point ! loosen the swingarm pivot bolt and the lump will fall to the ground .

Like bruce says it's harder to get the new one back in and lined up with the mounts , carriage jack makes it easier

[BruKen]

..... don't be suprised if the lump is still hanging in the frame at this point ! loosen the swingarm pivot bolt and the lump will fall to the ground .

Yea dont forget the last when trying to put it back in either. That squeezes the frame some. For the love of God, Allah, Bhuda (take your pick) I could NOT figure out why I was unable to get the lump back in when doing my rebuild. It just wouldn't fit .... !!!    !!!  :oops:  :oops: Took me a whole hour to figure that one out too  :roll:

[Rocinante]

Heath Robinson!:) Yeah, I guess. It was done in a toolshop in a one-horse town in the middle of nowhere. But it has held up through the years.

Thanks for the advices guys. But again, it seems, I´ll go against it. A part of me wants to buy new, but a strangely stubborn part of me says no way, you just replaced the head and blah blah. And I just visited the welder who thinks he can make the mounts stronger than original, and at a fraction of the price of a rebuilt engine, so I´ll go for it. Still crazy after all those years...

That is, first I will take the lump out of the frame, then I will inspect the frame and the other mounts. Then I will make a decision. The lump´s got to go out whether I´ll buy a new engine or not, so might as well get started.

I´ll start this tomorrow me think, if time allows.

[BruKen]

eh, you'll probably be fine, what do I care, I already ate my last and only hat. I just get more impressed by the ability of the tigger to stand up to abuse each and every day  :P  I'm keeping mine for sure :D

[Rocinante]

eh, you'll probably be fine, what do I care, I already ate my last and only hat. I just get more impressed by the ability of the tigger to stand up to abuse each and every day  :P  I'm keeping mine for sure :D

:)

I´ll never sell mine either. Then again, who would buy it?

[Mustang]

:)

I´ll never sell mine either. Then again, who would buy it?

There's a sucker ,,,erm I mean buyer born every minute , just look in my garage there are 4 of the black bastards in there  :shock:
hehehe

[Rocinante]

...that repair job looks suspect and that engine mounting system on the frame.... is positively a heathrobinson affair (so it may very well be an original hinkley job, but I doubt it) and could well be why your casing mounts keep cracking. If you are going in for repairs, dont repair an emergency RTW  "get me back on the road asap" botch job, return it to original or you could be facing the same problem in the future.

I´m not sure what you mean here Bruken, but I suspect you misunderstood something. The brackets you see is that last repair we did ourselves while on the road, not something out of Hinckley. We won´t be fixing a repair done on the road, all that will be removed and the original mount will have material removed around the cracks and refilled/welded. In addition the mounts will be increased in size to strengthen them further.

[Rocinante]

:)

I´ll never sell mine either. Then again, who would buy it?

There's a sucker ,,,erm I mean buyer born every minute , just look in my garage there are 4 of the black bastards in there  :shock:
hehehe

You want a green one? Just broken in and only ridden to church on Sundays..