Classic Triumph Bonneville

[Mr. Dazzle]

Yeah I could. It'll all come down to path of least resistance/lowest cost.

Like I said, it's not the original head so I'm not too wedded to it.

[Mr. Dazzle]

I glued that broken piece back on yesterday, it went together pretty well. I'd never really considered loctites to be an adhesive before, but looking at the figures its actually as strong as certain epoxies....

It takes about 10 minutes to 'set' but up to 7 days to achieve full strength. 24hrs should see it most of the way there though.

While that bit cures I've installed the intake side rockers. Everything rocks about smoothly now. It took me 7 attempts to get the box on with the pushrods in place. Thw rods are only retained by the fact they're wedged between the tappet and the rocker. Two of the cylinder head bolts go through the box and they only just clear the frame, so you have to jiggle the boxes to get the bolts in. That inevitably means the rods fall out of place.

Turns out I had been overly paranoid about backing off the valve clearances. If they're really really slack the rockers flap about while you're jiggling and fall out of place. Taking out a bit of slack worked a treat.

All of my turning over of the engine to see if things were moving (or not) also generated a big oil puddle from the rocker oil feed lines. That does at least prove the rockers are going to get a nice healthy oil supply Triumph oil pumps are not known for their longevity.

[Taipan]

If the bit unglued itself, what could go wrong?

[Mr. Dazzle]

Lots of oil would escape.

Theortically there'd be a big hole, but realistically its wedged between the rocker box and the rest of the head. Looking to my pic, the piece can only come out by going "up" but the rocker box is in the way.

I suspect the bolt hole in the broken off piece is primarily about providing clamp load on the gasket. The main constraints are from the primary head bolts which also go through the boxes.

[JackyJoll]

Triumph oil pumps are not known for their longevity.

Yes they are.

[Mr. Dazzle]

Well I've heard in lots of places that the pumps give all sorts of problems. Not so much the pump failing, but crap getting stuck in them. That's why I didn't drain the oil from the sump, apparently that's a good way to disturb stuff which then gets sucked into the pump.

[JackyJoll]

I just mean they don’t wear out like the gear pumps on some other old wrecks.

Oil reaching the rocker feed means the scavenge side of the pump is working.

[Mr. Dazzle]

Indeed.....and oil pissing out of the exhaust tappet block with the missing plug bolt means the supply side is working. So it's all working Hopefully one thing I don't need to worry about.

[Mr. Dazzle]

Head on and torqued down....



First off I very slowly turned it over with the plugs out and listened carefully for anything untoward. Everything runs around very smoothly, I was a bit worried the valve would clash with the pistons (even though this bike has had the same high compression pistons before - you never know) but all seems well.


I put the plugs in and gave it an explotirory crank over slowly again....much easier than I expected and lots of chuffing noises. After pondering for a sec I realised that id set the valve clearances finger tight before torquing the head down, so even when the valve were 'shut' the rockers were still holding them open a smidge.

Fixed that problem and tried again.

Ooof! She is gonna take some starting!

[Nidge]

Have you got the tool that allows you torque the head bolts inside the rocker covers without removing them? It’s a useful thing to have as you’ll need to re-torque the head a couple of times

[Mr. Dazzle]

The bolts in the what now?

This one has 4 bolts near the edge of each box, 4 that go through the boxes and then have another thread on the outside which is used to attach braces to the frame then 1 smaller one between the cylinders.

Which ones are you referring to?

EDIT: Like this. The long ones go through the rocker boxes. See how their heads aren't at the top. There are an additional set of brackets and nuts which use the upper thread.

[Nidge]

Ahh I think it may be different on the T140 they have some hex head bolts inside the rocker cover

[JackyJoll]

I was a bit worried the valve would clash with the pistons

If you temporarily set the valve clearances to minus one whole turn of the adjuster (so the valves are being held 0.040” off the seats) and the valves still don’t hit the pistons when you turn the crankshaft, then you have a safe valve to piston clearance.

[Taipan]

Lots of oil would escape.

Theortically there'd be a big hole, but realistically its wedged between the rocker box and the rest of the head. Looking to my pic, the piece can only come out by going "up" but the rocker box is in the way.

I suspect the bolt hole in the broken off piece is primarily about providing clamp load on the gasket. The main constraints are from the primary head bolts which also go through the boxes.

So it couldn't fall into the rockers and cause carnage?

[Mr. Dazzle]

No, even if I tried to push it in their I couldn't.

[KungFooBob]

Is it running yet?

This is taking way too long!!!

[Mr. Dazzle]

This is taking way too long!!!

That's deliberate

I'm well busy at work, I do a couple of hours of work a night 3 or 4 times a week on top of my normal 08:00-17:00. I've also got a 3 year old child to look after.

I have a tendency to get fucked off with annoying old rusty bolts and what not. Normally at work I just give the actual hands on work to experts Therefore I'm intentionally only doing an hour or so in the evenings a few times a week.

[Le_Fromage_Grande]

Best way to do it, only do as much as you want when you want, you're not being paid to do it

[Skub]

I've also got a 3 year old child to look after.

See it as an opportunity,get those little hands cleaning all the hard to reach places.

[Mr. Dazzle]

She'll probably inherit it one day, at which point it will be ~100 years old and about as welcome as lead paint, TB and asbestos are today