john.r.davies
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Posts posted by john.r.davies
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Wyn,
You may not need a vernier sprocket.
The standard Triumph (!) cam sprocket has the bolt holes that are equally spaced, but offset from the tooth centre:
Rotate it by 90 - timing is changed by half a tooth.
Turn it over - ditto by a quarter tooth
Turn over AND rotate - three quarters of a tooth.
So you can adjust the original wheel to +/-2 degrees
Easy!
John
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Rob,
When I start mine, it usually catches on three or four, and I can count the extra cylinders coming in.
Rather endearing as the old engine staggers into life!
I note that Richard blips the throttle to promote 'all hands on deck' - I find that kills the engine unless at least five are firing. Horses for courses, as it were.
John
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Wyn,
No basic arguement with marvmul's words, though brake fluid??? I recommend 'liquid paraffin', obtainable from your local pharmacist as a remedy for constipation! It is a water soluble oil, that doesn't foam or bubble, wets all the metal surfaces, and is easily washed away, from work piece and bench and is not corrosive or inflammable.
And rather than offer to supplement those words here, may I also recommend my own article on just this subject, over on the Totally Triumph Net? See: http://www.totallytriumph.net/spitfire/ski...your_head.shtml
John
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I agree, though I still believe that the battery stores the smoke that gets out of the wires at times.
Just make sure that it's connected the correct way around.
"Vintage style" batteries are available - can't point you to a vendor - but they just have an old-fashioned shape to the top, and you get a very limited range of sizes. A battery that has two dead cells is a dead battery, not pining, it has passed on. Your battery is no more! It has ceased to be! It has expired and gone to meet its' maker! It is a stiff, bereft of life, it rests in peace! If you hadn't nailed 'im to the perch........
Enough parrot sketch, but this is definitely an ex-battery. Please dispose of it carefully.
Suggest you pop around to your Halfords, who sell an amazing range of batteries at all sizes and prices, and operate a remarkable no-quibble replacement service (unlike a parrot shop) for three years after purchase. I know, they replaced one for me after the one I had bought was completely shagged out after a prolonged squawk - sorry - after trying to start an engine that was pining for the fjords - Stop! Stop!
John
Note to self - Try to get out more
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No, the powder is attracted to the part by charging it electrostaticly. When heated the powder melts and covers the part. No carrier coat. See: http://www.finishing.com/Library/pennisi/powder.html (the first on the list when I Googled for this)
John
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Villa,
It is, IMHO, a mistake to assume anything about a cylinder head, especially the amount already skimmed from it, unless it is a guaranteed new item. Measurement is always the best plan.
May I humbly refer you to my article about compression ratios and skimming your head, over on the Totally Triumph Net? See: http://www.totallytriumph.net/spitfire/ski...your_head.shtml
John
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Simon, Scuff,
Disc brakes are not like drums, in that there is no retractor spring to pull the pads off the disc when the pedal is released. Normally, the pads 'ride' on the disc when the brakes are not on, a very small distance from it. The pads should not be 'loose in the caliper'.
If the disc is unevenly worn, or the wheel bearing is loose, then the rotation of the disc will push the pads and the pistons back, off the disc to a position such as you describe. This so-called 'knock-back' can lead to inferior brake response and increased pedal travel, as the pads must move much further to clamp the disc.
I suggest that you check the tightness of the hub nut and wheel bearing, and that the disc rotates without any wobble (run-out).
JOhn
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Lee,
Agree with Andy about Pi - contrary to historical repute, it is also far more reliable than carbs, needs far less fiddling and no re-tuning every weekend. Set up by an expert, such as Malcolm Jones at Prestige, it's a fit-and-forget mod.
And if your brother would like, I know a man who wants to sell him a complete Pi kit.
John
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"Major expense is in cleaning the tank of petrol vapour"?
While this is an absolute before any welding, let alone brazing repair, it shouldn't cost a lot.
Anywhere that uses steam cleaners can do it - not wallpaper or carpets, but for lorries etc.
Couple of drinks?
It's just a flameless way of heating the tank to drive out the residual fuel.
John
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Tom,
"Learn something every day" - Aristotle (I think - I forget!)
Thank you - the A-type has O/d on 2nd gear?! What about later car or O/ds?
The 'small chassis' Triumphs only have O/d on 3rd & 4th, and the inhibitor keeps O/d engaged when changing between these gears. I now understand your concern if O/d disengages through neutral.
John
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David,
The Herald/Spitfire/GT6 overdrive boxes all have inhibitor switches that prevent use of overdrive in reverse. Is this not true of the TR3a/4?
And does the logic device really disengage O/d when you move through neutral from 4th with O/d to 3rd? How irritating, and how risky of over-revving!
There was a long thread over on the TSSC board about this, with object of switching O/d off automatically if you change down to 2nd. With the standard (and Standard!) set up, this means that the O/d disengages for 2nd, but re-engages when you go back to 3rd or 4th, which you probably would not want. The posters there developed a complex system of relays, but were rather squashed to learn that a chip could do it!
Is this what the 'logic device' does, rather than switch the O/d off when the lever goes through neutral?
JOhn
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Hogie,
A sudden increase in a low oil pressure couldn't be due to the release of a blockage downstream from the oil pressure take-off, clearing that would reduce the pressure.
The take-off is on the main oil gallery, just below the dizzy. Upstream from there are the oilways to the rear crank main journal, the rear camshaft bearing and thence the rocker shaft, the oil filter, the pressure releif valve and the pump. A blockage release in the bearing oilways would also reduce pressure, so in your case, the problem is isolated to the oil filter or the relief valve, presuming the pump is good.
Oil filter. I don't know if a filter problem could partly block flow. I wonder if a non-drain valve, just a rubber flap, in an aftermarket disposable filter, could be faulty?
Relief valve. The valve is not a needle valve, but a 'pin' with a half inch (?) wide face that bears on a machined face in the block. I've seen valves whose removeable 'pin' face is extremely and assymetrically worn. This might be okay, if the block face has worn in concert with it, but in renovation the pin will be removed. Assembly with the faces now out of register would lead to a permanent leak, a by-pass through the valve back into the sump. If, eventually, the pin rotated back into register, the pressure would suddenly rise, as the by-pass ceased.
Such a worn valve really needs the block face to be remachined, not something that can be done without a complete strip down. Examination of the 'pin' face, and with a probe the block face, might tell you if you have a problem.
Hope that helps!
John
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Brian,
IMHO, lightening the flywheel is something you do only on a full-race car, to extract the last fraction of a percent of acceleration.
It will ruin your slow running and tickover and if carried to the extreme, risks weakening the flywheel.
I don't believe that you will ever find a real use for it in even a fast road car.
I did this to my race car, and couldn't tell the difference.
But maybe that's me.
John
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You sold it three years ago, and you are still worrying?
Is it keeping you awake at night?
Has the buyer called in that guarantee you joked about?
If you checked the valves and rockers, how about the distributor?
Nothing else goes twice as fast as crank speed.
John
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Hang on, Cinnie.
Hodgie hasn't told us how big his M/c is.
It's hydraulics, remember those?
A smaller master demands longer travel, but exerts a greater pressure at the slave.
Force1/Area1=Force2/Area2 so F1xA2/A1=F2.
See for example: http://www.grc.nasa.gov/WWW/K-12/WindTunne..._principle.html and lots of other educational sites.
In practice, of course you are right that too small a master will demand to great a travel.
But until Hodgie tells us the size of his M/c, my advice still stands.
Physics, the theory of everything!
John
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Hodgie,
"Uprated" master cylinder? How?
If you change now to a smaller diameter cylinder, you will get more pedal travel, but the force at the calipers will be greater. That should help.
And which Mintex C-Tech compound are you on? 1155 and 1166 need too high a temperature to work well on a road car. If you have these, go for 1144.
John
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Eli,
Is the glare seen in the area of the screen swept by the wipers? Could it be that 'X' years of use have covered that in micro scratches? It may be possible to polish them out - Frost do a wind screen polishing kit, that I used for just this purpsoe with some success. It won't deal with scratches that are so deep as to be felt with the fingernail, but for microscratches it does well. Long winded process though.
And; do you see glare when not looking through the wind screen? Does the light 'flare' around the source?
If so, you would do well to ask for an opticians opinion - your glasses, if any, or your eyes may need attention.
Hope not!
John
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Don't know about South Wales, but Malcolm Jones of Prestige is in North Wales, well the Marches any way 77 Box lane, Wrexham, LL12 8DA, Tel \ Fax 01978 263449.
If advice here can't ehlp than he is most helpful, and his metering unit set-up rig is remarkably accurate, even when you and your car aren't there!
John
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My mistake has been pointed out elsewhere - this was rebuilt 15, not 42 years ago, so certainly from a complete car, and as certainly either a crashed or terminally corroded one. No qquestion of a coachbuilt body on an original chassis, so no 'historicity'
But a 'hideous waste of a decent chassis'! That's a bit cruel, Rob!
It has to be a judgement if you have a seriously damaged body.
Restore it at great expence or start again with something simpler.
I think this is a refreshingly different car, that doesn't purport to be something it isn't - compare those TR7s made into Ferrari copies. I hope the owner sells it. It would be a shame to scrap it, especially just to obtain parts.
John
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Anyone noticed this?
http://cgi.ebay.co.uk/TRIUMPH-TR4-SPECIAL-...1QQcmdZViewItem
I can't comment on the authenticity.
Were TR4 chassis sold to coachbuilders, as Bentley chassis were?
Or would this have been rebodied after a crash?
I'm tempted, but other projects prevent!
John
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Okay,
Just back from the FISC race at the Nurburgring. Anyone who has been 'Ringing will know that I still have that smile on my face, even though I rubbished the diff in the race. Thirteen laps of the Nordschleife and I'm a 'Ring junkie.
There were a number of TRs as well as TSSC cars there, including Keith Files' TR6 and Hugh Maund's TR7/8.
Most of my pics were of the Spitfires, GT6s. Heralds and Vitesses, but Hugh's car, that lost it's bonnet on the fastest straight of the 'Ring was the only TR I took. Nice TR ?4 behind though.
Happy now?
John
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My apologies for not posting to thank Chris and his friends. Since getting back I have been only able to sleep after work. It was one Hell of a weekend!
I managed to get in thirteen and three quarter laps of the 'Ring, four in my road car, so I'm a 'Ring expert now! Not! Though that practice did help a lot in the little of the race that I did manage before the diff exploded - the Midget I was behind celarly didn't know the turnin points that I did, and I was past him by Bergwerk before grinding to a halt at Klostertal.
You were rather kind to the weather, Chris! Despite, possibly because of intensely hot sunshine in the mornings, most afternoons (not Saturday) were marked by some frightening overhead thunderstorms, with simultaneous flash and bang. The Friday free practice was very wet,but I'm proud to say that I survived, and that the Porsche drivers weren't that agressive, mostly.
Like General MacArthur and Arnie, "I'll be back!"
And the opportunities are there. Not only is there the FISC series that we attended, the Wynn's GT Cup goes to the 'Ring. It has a meeting there in October and the FISC series is at Zandvoort in September. See: http://www.tr-competition.de/doc/2006/wynnscup.php and http://www.fisc-europe.org/calendar.php
John
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Tony,
If you have a bolt that you know is the correct size, but dirt/corrosion/powder coating makes it too tight in the hole, AND you have another bolt the same, adapt one bolt to be a DiY tap. Cut three or four slots across the threads parallel to the length as for a true tap. Run it into the hole threads with lots of to and fro and withdrawals for cleaning. The slot edges will act like the lands in a tap and take out the powder coat.
I KNOW it's a bodge and the cut bolt will be useless after, but useful if you have no tap of the correct size. You can do the same with a nut, as long as it is large enough to get a hacksaw blade into the hole (grind down the thickness of the blade!)
John
Fuel, compression
in TR6 Forum
Posted · Edited by john.r.davies
Roger,
What an interesting site - thank you!
MON and RON do not necessarily correlate, MON is considered the more severe test, as mixture temperature and spark advance are greater. Premium unleaded 995 octane RON is equavalent to 85 MON
Strictly, and by chance as the apparent matching of numbers is a coincidence, a CR of 10 needs 100 octane fuel. But the volumetric inefficiency of most engines also means that a calculated CR of 10.5 can survive and thrive with fuel of 97-98 octane (RON). For a Triumph engine, the possibilities of increasing that efficiency are limited, so I'm happy to use that.
John