Nick Moore

Stripping the tandem master cylinder confirmed what the rust powder in the reservoir had hinted at - the bore has rusted where the rear seal sat for forty years. You can see the rust in the second photo (damned hard to take a photo of this, I ended up using a macro lens and shallow depth of focus). I think the pits are too deep to cure with a honing stone, so it needs resleeving. The front and rear sections are different diameters, making it a tricky and no doubt expensive job. Moral - as much as we bitch about reproduction items being crap, don't assume that NOS parts will be the same quality as brand new after decades on a shelf.

If the wheel alignment hasn't been done since you changed the spring, it will likely have toe-out, making the handling unstable. As for driving it and seeing if the spring will settle - if it's a good spring it shouldn't settle much. If it does, it hasn't been tempered properly. And in the meantime, is the handling safe? I'd throw in a 3/4" or 1" block and get the wheels aligned. If it does settle over the next year then you can substitute a thinner block, and probably sell the old one here. Just checked - my GT6 sits with 57cm from the ground to the tops of the rear wheel arches. That's a good height.

Been fiddling some more. Some have said that the tandem system will never work properly, but I'll persevere a little longer before throwing in the towel. The PDWA's leak seems to be from a poorly made pipe flare. I have a couple of flaring tools but am not very good at making the flared ends. Some are OK, but this one isn't. A professionally re-flared pipe end should cure the leak. Despite the master cylinder being new old stock, a thin layer of rust has formed in its reservoir, suggesting that the bores have been exposed to the air and rusted while in storage. My guess is that the rear piston has been gummed up with rust - the two pistons aren't  connected to each other except then the front one pushes the rear one. Just because the front one returns, doesn't mean the rear one will. I'll strip it down, inspect the seals and bores, and see what's what. Hopefully the bores will only need honing. It needs a 12mm Allen key to dismantle - and of course my set stopped at 10mm - so a 12mm key is on the way from eBay. To be continued... On a happier note, the Teflon spring buttons are in. Some buttons are thicker than standard, making the rear of the car higher, but that's not the case here. She sits as low as before - not so low as to scrape on the ground, but low enough to make getting out amusing for onlookers! The spring leaves were slathered with grease before reassembly - fun job, that.

Not a stupid question at all! It probably isn't centred - I've had a look but can't say I was convinced that the shuttle's depression was visible. And some people have suggested that some PDWAs act as an isolating valve. The cross-sections of mine seem to indicate that it doesn't, but I haven't pulled it apart to be sure. Yet. Consulting Mr Google, it looks as though the master cylinder has two pistons, and just because the front one is free to move it doesn't mean that the rear one isn't stuck. That may be my problem. Even if I fix it though, it doesn't mean that the one-circuit-boosted brake system as I've built it will work well. Maybe I could fit a second booster for the rear brakes... On a happier note, I just fitted a set of teflon leaf spring buttons, made by a guy named Ondrej in the Czech Republic. He's on eBay as 'Oakman-cz'. He sells them in both standard thickness and thicker for saggy springs. I'm happy with them

The discussion in the 'Brake Servo' thread about dual circuit brakes (Sorry , link no longer available) is very relevant to my Green Monster right now. In short, the brakes have been plumbed up as per US-1972 spec, but the rear brake circuit isn't working. Background: US-spec 1972 GT6s, which mine was, had dual circuit brakes. They had a tandem master cylinder and a Pressure Differential Warning Assembly, which lit up a trouble light on the dashboard when one side started to leak. I've replicated this setup and added a servo for the front brakes. That's what Triumph did as well - the back brakes remained unboosted. The front circuit seems to be working. The servo and calipers were easily bled, and there's some resistance in the pedal. The rear circuit isn't working though. There's some fluid in the rear line at the PDWA, but none at the rear of the car. I think the problem is in the master cylinder and the fluid has simply moved through under gravity. Oh, and the PDWA leaks - fortunately two pack paint is more resistant to brake fluid than lacquer 🤔 So I'm at a crossroads. I can persevere with the tandem setup or replace it with a simpler single circuit system. To fix the current setup, I'll have to strip and overhaul the pretty complicated tandem master cylinder and the PDWA. Both were New Old Stock as refurbishment kits are hard to find, especially for the PDWA. Just ask Wim. Even with that done, however, I'm still not sure that a boosted front and unboosted rear is a good idea. I have Canley's alloy 4-pot calipers and large discs up front and strongly suspect that the standard rear drums won't do much compared to boosted uprated front brakes. The alternative is to change to a single circuit system, with the booster operating all the brakes, and no damned PDWA - in other words, change to a UK-spec system. The 'pro' is that it'll be cheaper, will eliminate potentially leaky components and will keep the rear brakes working proportionally to the fronts. The 'con' is that if the system leaks it'll loose all its fluid, just like my Herald (although that's never happened). As a backup, I could fit a low fluid level indicator to the master cylinder cap to warn if the system develops a leak. Something like this: http://www.carbuildersolutions.com/uk/brake-fluid-reservoir-cap So, opinions: rebuild (again) the complicated and possibly poorly designed dual circuit system, or go single? Either way I want to keep the booster, as I like light brakes.

I read somewhere that Lockheed servos tend to have a jerky action - push, push a bit harder, and then bam! In comes the servo! That certainly matched my experience with a Lockheed on my Herald. I rekitted two separate servos and they both had the same off-on character. They were replaced with a Bendix 'Hydromaster' servo, which works perfectly. My GT6 has a brand new VH44.

2003 wrote:Good point, though the link in question is scrap anyway; Sorry , link no longer available And have got two new canleys trunnionless links. Ah, jolly good then. Carry on!

The tapered hole in the early upright will be smaller, so you'll need to get it reamed out before a larger stub axle can be fitted.

Whatever it is for, it is very fugly and should be thrown a long way from the car! If you want to mount extra switches, a more aesthetically pleasing way is to mount them below the dash. Of course, removing it will leave a hole. You could fit an indicator lamp for an electric fan or overdrive. Or you could make the hole bigger and fit another gauge, such as oil pressure.

You're on the right track. A cylinder head shop may want to give it a skim anyway to be sure it's flat. More of a skim will increase the compression ratio, but they should measure the chamber capacities to be sure how much to skim off. A 9.5:1 CR is fine for a road car. Hardened valve seats are a good idea. Check the valve guides for wear. If the guides are worn, they can be reamed and fitted with inserts (eg K Lines) rather than replaced. There are aftermarket valves available that are said (mostly by the sellers) to improve flow, but unless you're going to have the ports smoothed out, the standard valves will be fine. Larger valves make it harder to fit hardened seats, and anyway, the larger a valve is, the nearer it is to the wall of the combustion chamber, which impedes flow. As for 'porting and polishing', it's a black art. Some gurus proclaim they know how to vastly improve flow, but the more you read, the more confused you will get. My impression is that road engines don't need anything more than matching the ports to the manifolds, and cleaning up any rough casting ridges. Get the shop to check the valve springs. If they're all similar rates then chances are that none have softened, and they can be reused. 'Uprated' springs are generally stiffer and will increase strain and wear on the lifters, camshaft lobes and the block journals that the camshaft runs in, for no performance benefit. Also check your rocker shaft and rockers for wear while they're off. If they're worn, they can be replaced.

Another vote for the Carcoon. My Herald has lived in one for ten years, split between two countries and vastly different climates. The outside Carcoon is best on flat, level ground, as the bases of newer versions are double skinned and the top skin will slide over the lower layer on a slope. The silver skin keeps the car shaded and cool, so preventing sun damage to the paintwork and interior. The cover's extremely waterproof - we had a tropical cyclone last week and the Herald stayed dry. The circulating air stops it sweating in humid conditions. It also deflected inch-sized hailstones last year that caused hundreds of broken windscreens and dented cars - they just bounced off! On the other hand, it's not so good in wind as it has a large surface area and gets blown around. Back in New Zealand it was defeated by snow, but even then the car stayed dry. And the cat thinks it's a bouncy castle ::)

Another vote for the Carcoon. My Herald has lived in one for ten years, split between two countries and vastly different climates. The outside Carcoon is best on flat, level ground, as the bases of newer versions are double skinned and the top skin will slide over the lower layer on a slope. The silver skin keeps the car shaded and cool, so preventing sun damage to the paintwork and interior. The cover's extremely waterproof - we had a tropical cyclone last week and the Herald stayed dry. The circulating air stops it sweating in humid conditions. It also deflected inch-sized hailstones last year that caused hundreds of broken windscreens and dented cars - they just bounced off! On the other hand, it's not so good in wind as it has a large surface area and gets blown around. Back in New Zealand it was defeated by snow, but even then the car stayed dry. And the cat thinks it's a bouncy castle ::)

Yeah, I tried the string'n'shove method, to much amusement from the neighbours but no movement from the screen. Even with it firmly engaged at the bottom, it was too tall to fit under the folded over flange at the front of the roof. The fitter said it was a real bugger to force down further so that it could move back into the windscreen frame. When it comes back next week it will be about 6mm smaller top to bottom. If that doesn't work I will buy a pair of Biggles goggles.

Despite three visits by a mobile windscreen fitter, my GT still doesn't have a windscreen. The first fitter found that the windscreen, made here in Australia by PGI, was too large. PGI ground it down slightly to exactly match the dimensions in their catalogue - for free, which was nice. The second fitter took the screen back to the workshop to fit the trim to the rubber. It took them a couple of weeks but they a managed to get the strips in place. Yesterday the fitter came back, got the windscreen in, but found that PGI still hadn't trimmed the screen down far enough. In the process the stainless trim popped out again! So, the windscreen is back at the workshop, where it will get ground down by another 3mm. Then they'll refit the trim again, and come back for Round Four. It seems to be a combination of problems. Firstly, the windscreen has been poorly made. If I had an original Triumph windscreen, it would be the right size. But try shipping a windscreen around the world! You'd get something... Secondly, the rubber is aftermarket and although O'Briens Glass haven't criticised it, it may be causing problems. And thirdly, the design of the trim itself has the professionals almost beat. They've never worked on a Triumph before but as they say, it just doesn't need to be this hard. Stay tuned for the next exciting episode in 'First Glass'!

My Herald's chassis was dip galvanised almost twenty years ago and is still rust-free. Holes were drilled to let the zinc into the cavities, and any trapped air out. It distorted slightly but within tolerances. It was brush-painted in etch primer and Smoothrite (the original recipe which contained toluene). If I'd heard of POR-15 back then I would have used it, as the Smoothrite is petrol-soluble and a few leaks have attacked the finish. Given the success of galvanising my Herald's chassis, I wanted to do the same to my GT6 but there wasn't a dip-galvanising works nearby when I was restoring it. Instead it was shot blasted, painted in an epoxy normally used for mining equipment, then brush-painted with POR-15. The front section has been finished with tie-coat and body coloured enamel, again brushed on because I didn't have spray equipment. I'll inject wax into the chassis rails.

If the earth strap at the base of the steering column has disappeared, consider replacing the joint between the column and steering rack with a UJ. They're all steel, so no need for an earthing strap. But better is that a UJ eliminates the eight small rubber cup washers in the existing linkage. They're why the column isn't earthed, but they also go soft and squishy with age, making the steering less direct. There are a couple of models of UJ on the market. Bill from Rarebits sells the best variety. So, better steering and the ability to toot at anything you can't steer round.

My choice would be for the first option: 88 on, 79 off. The fan draws a large current, so the switch will last much longer if you use a relay.

I'm copying the diff catch tank idea from my friend Rocky, who was one of the Subaru diff conversion pioneers. On his first few drives, he found the back of his Vitesse was getting covered in oil. The problem turned out to be the lack of a diff breather. The original Subaru rear cover had a breather in it, slightly fancier than Triumph's split pin but doing the same job. The cast alloy plates for mounting the diff to a Triumh chassis didn't have a breather, so the diff would pressurise and force oil out past the seals. Live and learn! Rocky's solution was to take a pipe from the top of the diff into the boot, and have it vent into a catch tank so that any oil forced out wouldn't end up on the road or under the car. In theory, very little oil should be pumped out as the breather comes from the top of the diff plate. In practice, we'll see. It will be easy to see how much is being forced out, whether the amount remains constant and it will also make it easy peasy to top the diff up!

As if I haven't heard that before As always, cunning beats excess.

Yes, green light at TDC. I checked mine yesterday in case the distributor's clamp had slipped, and it was still at TDC. Very easy to check! The Spitfire 123 Tune is a replacement for a Delco dizzy, and my car had a Lucas 25D, so I wanted to be sure that the Lucas clamp was holding a Delco-style dizzy. And it is.

Not sure if EFI per se affects octane tolerance in high compression engines, but accurate ignition timing does. In a lot of cases, pinking can be reduced by retarding the ignition, at the expense of power and fuel economy. For example, my Herald has 9.5 compression and runs happily on 95 Octane. I plan to play with the 123 ignition and see if I can develop an advance curve that lets it run on 91. As for the GT6, we can get 98 Octane here if necessary, so it should be OK. Today was spent raising the nose of the diff to try and get it on the same angle as the engine. The reason for this is that a driveshaft's centre section doesn't rotate at a constant velocity, thanks to the UJs. However, if the engine/gearbox and rear axle assemblies are parallel, the effect cancels out and both driveshaft flanges turn at a constant velocity. If they aren't parallel though, the output flange's speed will fluctuate. My cunning tool for measuring the angle of the engine and diff was an iPhone! Also useful for levelling pictures and squaring up doorframes The diff and engine were about 4 degrees from parallel, meaning that the front of the diff had to go up, or the back of the gearbox drop down, or the front of the engine move up. (The engine doesn't really sit in the car at 83.5 degrees, by the way - my garage floor is on a slope, as the garage is dug into the hill under the house. No, I wouldn't have built it that way either 🤔 I trimmed the bushes at the front of the diff and was able to raise it about a centimetre. That was as far as it could go, as the nose is almost touching the handbrake mechanism. It's still about 1.5 degrees from being parallel with the engine, which isn't ideal. i'll have to see if there's any vibration when it's on the road. If there is, it may be possible to raise the engine a few millimetres. There is definitely no room to drop the gearbox any lower.

The fine-tuning will definitely be done on a rolling road. I think I know enough to set up the Megasquirt for the running-in period, but not for the clever stuff. It's 2.6L, 10.8 compression and has a long overlap camshaft, and will have proper 6-3-1 headers and ITB injection. No idea what the horsepower will be - for a road car, my goal is a nice fat mid-range torque curve. Mitch, the hose is a breather. Triumph diffs have a split pin in a hole to release any pressure buildup, but the Subaru diff's breather is in the alloy case that gets thrown away during the conversion. I'll have a little expansion bottle in the boot, so that any oil pumped up can run back into the diff when it cools. It also makes it easy to top up the oil!

I finally got around to a job I'd been dreading - dropping the diff (again). Gave the cat a helluva surprise. The spring mounting plate on the Subaru diff is large and makes it tricky to fit the diff. If you simply jack it into place, it hits and crushes the delicate handbrake cable guides. Guess how I figured that out... So today I dropped the diff, repaired the cable guides and slotted the diff back in...carefully. Actually the whole job wasn't as bad as I'd feared, and took about four hours (including head-scratching). The diff took less than an hour to refit. Maybe I'm actually getting better at it, or more likely the mounting slots in the chassis have been widened by past diff-fitting struggles. Anyway, the handbrake cable now moves freely, and we finally have a functioning handbrake. Tomorrow's job is to raise the diff's nose a few mm so that it is parallel to the engine. I have a special tool to measure the angles...

The tailgate now has a couple of 1/2" drain holes in the lowest point. The bare metal has been painted, but I could see through the holes that the interior of the door is unpainted, covered in surface rust and damp in spots.   Why didn't Triumph drill some drain holes, for heaven's sake? Still, better to catch it now than find rust bubbling through the panel later. I left the back of the car toasting in 30C sunshine this afternoon to try and dry out, and when I'm satisfied that the moisture is gone, I'll pump in some Fisholene or similar. A mobile windscreen fitter came around yesterday, but couldn't fit the stainless trim to the rubber seal. He took it back to the depot to get help and better tools. He'd promised to fit it today, but rang back sheepishly to say that it was a 'difficult' job and he probably won't have it fitted until next week. Actually he didn't use the word difficult, he used a technical term

Thanks guys. It's already had some water in there, so I'll drill some holes in the bottom, leave it in the sun to dry thoroughly - Aussie's summer sun will dry anything - and put grommets in the top holes. Best I find out now how to avoid water and rust traps! And thanks for the stud tip Marcus, it's a good one.