Topic: TRIBSA

[Terry in Australia]

I don't know, you look pretty handsome with your helmet on Simon? (just don't take it off........... )

[simon#42]

this is why i always buy expensive full face helmets terry !

[Terry in Australia]

Classy!

[martin99]

You too should get a room   

[Terry in Australia]

Hey we're only keeping this thread warm while we wait for the next exciting chapter of "Martin saves another Pommy sh1tbox", ha ha!

[martin99]

You baarstard, you made me spit my toast out

[vfourfreak]

Perhaps the PO was also using the "kitchen utensil" method to do some work on the head Martin. An egg whisk to redo the valve seats possibly ?

Kev

[martin99]

Perhaps the PO was also using the "kitchen utensil" method to do some work on the head Martin. An egg whisk to redo the valve seats possibly ?

Kev

Hey Kev
Not sure about the kitchen utensils, looks more like he used garden utensils to me!

[Terry in Australia]

Well I think it's terrible that you keep blaming a PO Martin, when in fact, it's probably just the way they came out of the factory..........

[martin99]

Well if that's the case, then the bloke responsible is probably six feet under or in a nursing home, which is where I might be by the time this is finished 

Anyways, drew a blank at the weekend auto jumble, today I've ordered some more bits which should be here Friday, so you won't have long to wait for the next thrilling instalment. I know it's hard mate, but please try and be patient and keep an eye on the old blood pressure 

[martin99]

It's all in the preparation right? Well, not exactly. All the preparation in the world won't save you from impatience and a lack of common sense.

Tappet blocks. I read up a lot on fitting Triumph tappet blocks, the more I researched the more worried I got. Not as easy as whacking them out and whacking them back in. You have to get them aligned - exactly. Not just so the nub on the end of the retaining bolt enters the hole in the block, it's slightly smaller than the locating hole. Enough for the block to twist substantially and skew the followers out of square to the camshaft lobes. So some precision is necessary. At the very least, you must have the correct tool - a two-pronged drift that fits in the follower tunnels in the block - to avoid damage and to be able, with the help of a wrench, to 'twist' the block as you drift it in to correct any misalignment.

The 'proper' tool is not particularly expensive, but expensive enough for me to decide to make my own rather than invest in a tool I'm only likely to use once....

I found that an old Norton conrod bolt was a snug fit in the follower tunnels in the block. I removed the threaded portions and cut a piece of 10mm plate to attach them to...



Half a CB750 rear wheel spindle later and a trip to the father-in-law for a bit of welding, and I had my own 'proper' tappet block insertion tool...



Next I had to figure out how to hold the cylinder block secure while I drifted the block in. I had read a tip on one of the Triumph forums about using a piece of 7x2 timber with holes cut to accept the cylinder sleeves and 'ears' of the blocks, thereby keeping the base fully supported...



I had also been warned about the possibility of the sleeves moving once the cylinders were heated up, so I made sure they would be held in place securely...



The new block for the exhaust side and correct locating bolts. I would be re-using the original (inlet side) block...



Both blocks and their corresponding homes in the cylinder base got a dressing with 1000 wet and dry, to remove any ridges and nubs that might pick up as they were driven home. Then the cylinder block went into the oven for twenty minutes at 200* C. She was not happy. I forgot I had given the sleeves a copious coating of WD40 after honing them, and as it evaporated it stunk the kitchen out. I actually quite liked it  ...



I don't have a picture of the blocks being drifted in - it was a two handed job. I did it on concrete rather than the bench, to prevent any 'bounce' that may cause damage. I started with the new block, a few light taps with the club hammer, really using only the weight of it, saw it go in to within an eighth of it's seat. I stopped after every couple of taps, checking alignment as I went. At an eighth out though, it tightened up, which is where I should have stopped, knocked it out again, and investigated. But not me, oh no, I was close, a couple more, significantly heavier 'taps' with the hammer saw it seated home. I lifted it up to inspect my precision work, and my heart sunk. Fck!...



Impatient, stupid. I couldn't bring myself to look at it for the rest of the day, and went into a sulk that would put a little girl to shame. Well, important things matter right?

Anyway, now I've had time to reflect upon my back-street balls-up, and sought a bit of advice, I don't think it's quite the end of the world. The cylinder base distorted slightly and I have managed to dress it flat again....



But oh sh1t that crack 

So I need some ideas fellas. The tappet block is not going anywhere (incidentally, the inlet side 'fell' in and nipped up tightly as the cylinder cooled down). A welded repair would be the ultimate fix, but just not financially viable. It may also warp the base of the block and turn it into scrap. I can fit the cylinder block as it is but I am concerned that once things get hot I may see an oil leak there (not that I predict no oil leaks - it is a Triumph after all). The pictures might make it look worse than it is, the crack can best be described as 'hairline', but I would be happier if I could seal it up. Does anyone know of a 'liquid metal' type product with the right viscosity to leach in there? I thought about 'V-eeing' it slightly and using some JB Weld (still might) but as always would welcome your comments. Just please don't tell me what a prat I've been - already know that!

 

[Bankerdanny]

Can it be welded?

[martin99]

Yes, it could be welded, but that would necessitate removal of the tappet block and re-machining of the hole it sits in. Both cylinder block and tappet block are aluminium, and I've been led to believe the room for error here is large, with the potential for warping the base or hole or both. Removing the tappet block might make things a whole lot worse (it's almost friction-welded in there I reckon, would probably have to grind it out), and to hand it to a professional machine shop is going to be expensive. I'm open to all suggestions though, so if people here think it can be done, I'm willing to listen.

My first thought was to try and find another set of barrels, but having spoken to my mate, who's been restoring Triumphs as his livelihood for thirty-plus years, it is very unlikely that I'll find a set in better condition than these, even taking into account the damage I have inflicted upon them.

[grcamna2]

I like the idea you mentioned of the liquid epoxy.

[jgger]

I think that I read something on this site about a guy that was using a product called alumaweld. You use a propane torch and it looked pretty strong. The only bad part is that he got it at Harbor Freight, I don't think they are on your side of the pond.

I may have read it on the 305 forum. I will see if I can find it and post a link if my limited computer skills allow that.

Good luck with it, just remember round hole/round peg square hole/square peg. (I feel your pain, but couldn't resist.)

[754]

Get some epoxy or similar that is liquid, let it run in the crack, wipe off xcess..
Make sure its filled, then cleanup and paint.....

[martin99]

I think that I read something on this site about a guy that was using a product called alumaweld. You use a propane torch and it looked pretty strong. The only bad part is that he got it at Harbor Freight, I don't think they are on your side of the pond.

I may have read it on the 305 forum. I will see if I can find it and post a link if my limited computer skills allow that.

Good luck with it, just remember round hole/round peg square hole/square peg. (I feel your pain, but couldn't resist.)

If you can find a link I'd appreciate it. I Googled 'alumaweld' and got a bunch of answers about boats!

[martin99]

Get some epoxy or similar that is liquid, let it run in the crack, wipe off xcess..
Make sure its filled, then cleanup and paint.....

Thanks for the suggestion Frank, I'm tending to think along those lines. What I really need to know though is which product to use, and if there is one thin enough to get into the crack 

[martin99]

And also, should I grind a vee into that crack a little to present a larger surface area for the epoxy to take hold?

[Retro Rocket]

And also, should I grind a vee into that crack a little to present a larger surface area for the epoxy to take hold?

The one thing that would concern me when it comes to using epoxy on an old Triumph engine, is the porosity of the aluminium, there would be plenty of oil and contaminants soaked into it, if it were me,  I would be getting that block tigged up properly... You shouldn't have too much trouble finding someone to do it for you..

[Terry in Australia]

Don't worry about it Martin, it probably came out of the factory like that! JB Weld (or Devcon if you're feeling wealthy) will fill that void in your life, and it is certainly thin enough to run into just about any crack when it's first applied.

Don't worry about it melting when it gets hot, I used "Araldite" to glue a broken fin together on my Suzuki GS1000's cylinder block and it was still holding it together 12 years afterwards when I sold the bike. Just make sure the crack is clean, oil free, and "V" it with a dremel tool to allow a decent pool of it into the damaged area, which will give it (the epoxy) more strength. 

I used plasticine to make a "dam" around several repairs I've done with epoxy, it just allows you to fill the repair area, and you can just file down the excess material sitting "proud" of the repaired area.

And lastly, remember that one day when you eventually sell it, someone's gonna start a thread somewhere telling the world what a butcher the PO was! Talk about cruel irony............

[jgger]

I think that I read something on this site about a guy that was using a product called alumaweld. You use a propane torch and it looked pretty strong. The only bad part is that he got it at Harbor Freight, I don't think they are on your side of the pond.

I may have read it on the 305 forum. I will see if I can find it and post a link if my limited computer skills allow that.

Good luck with it, just remember round hole/round peg square hole/square peg. (I feel your pain, but couldn't resist.)

See if this works http://www.alumiweld.com/index.html

If you can find a link I'd appreciate it. I Googled 'alumaweld' and got a bunch of answers about boats!

[jgger]

http://www.alumiweld.com/index.html

Stupid me, it's alumiweld. I wish I could I could remember where I saw the write up on this stuff, I was impressed. That link should get you in the door.

[Terry in Australia]

Yep, that Alumiweld stuff is fantastic, I always watch the dudes demonstrating it with envy, then I buy the rods, take them home, try it myself, give up, and use my mig instead. If you're gonna take any heat to it though Martin, I'd take Mick's advice and get it TIG'd, only a small amount of localised heat required to fill that puppy.  

[jgger]

Yea, but he could tell the Mrs. he is making cookies and heat it in the oven again then fix it on the kitchen table.........I'm sure she wouldn't mind.