JohnC
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Posts posted by JohnC
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Out of interest, what manifold are you using? I used to have a TT1200 6:2 manifold which gave a horrible loss of torque in the mid range but came on song around 5000rpm. Apparently that was caused by pulses interfering with extraction at mid-range rpm. The manifold was designed for high-end power, so it was working as designed, just not as I wanted it! I changed back to the original cast iron manifold and things got better straight away.
Cheers,
JC -
TBH the engine (and heater) are hardly an issue compared to the body and chassis. If the body and chassis are good then maybe have a haggle for the fun of it. After all, how many hours will it take you to replace the heater? And how much to have the engine fully reconditioned? With the price of TR5s it's getting close to a drop in the ocean. A body resto though, that's a different story.
My 2¢ worth. And I can't afford a TR5 so I'm just jealous
Cheers,
JC -
1 hour ago, Mike C said:
I fitted an original Pertronix Igniter back in Oct 2006, I've never had any problem with it.
Likewise. Jan 2006. What is now known as an Ignitor 1. I still carry a spare set of points etc in the glovebox but never had to use it in 18yrs. I have always tried to heed the warning to not leave the ignition on with the engine not running, but not religiously.
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Ummm. Just because it's not fossil fuel based doesn't mean it has no carbon! Take ethanol. Sourced (mainly) from plants, but formula CH3CH2OH. If you heat up "no smoke oil" enough, it will burn! Maybe its secret is a very high smoke point. Like rice bran oil.
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Hi @John McCormack,
I've experienced a very similar/identical problem - cranking time increasing - a couple of times. Even though you may have found a work-around for your starting problem, these may provide food for thought.
The first was a tired battery which led to low fuel pressure when cranking. I diagnosed that with a pressure gauge in the fuel line. Interestingly, letting the pump run for a little while before starting somewhat alleviated the problem. The cranking speed was not noticeably slower BTW. Like you, I have a Bosch pump. At the time, it was fed by the old wiring, which I suspect magnified the problem. Since then I have upgraded to nice fat wires, using the original ones to switch a relay.
The second time was leaky injectors. The symptom was that the car took a *lot* more cranking after being left for only a few days. I diagnosed the problem by replacing the black injector lines with translucent white ones. I could see the size of the air bubble increasing daily. Not equally across all injectors BTW. I tested the injectors using an airline and a bucket of water, and could see bubbles well before the 50psi point. Crude, I know (air vs petrol). Changing the O rings didn't fix the problem so I sent the injectors off to Peter Bower for re-seating. Problem solved (pity he's no longer in business).
Incidentally, even with reconditioned injectors, there is always a small air bubble in each injector line after the car has sat for a while. So I figure that the poppet valve isn't a perfect seal, and that when the car is hot a bit of fuel vapour makes its way out, being replaced by air. And before anyone jumps in, yes, I do know all the non-return valves are working fine. I had them tested when I got the injectors reconditioned.
Hope this helps,
JC -
Interesting info that there is more than one design of s/c out there. It explains a mystery I've had with my car. When I got the car nearly 40yrs ago the s/c was inserted into the mounting plate from the rear of the car, and the s/c had a machined face against the plate (i.e., the face of the mounting flange closest to the bleed nipple was machined).
When I got a replacement s/c many years ago the front-facing side was not machined but the rear-facing was. So without thinking I mounted it from the front so that the machined face was against the mounting plate. The result was that the clutch periodically dumped its fluid as the piston popped out of the s/c. Not every time (that would have been too obvious). It took me months of head-scratching and wear elimination before I realised what I'd done. Fortunately I have plenty of photos so I eventually spotted the change.
I now have the s/c mounted from the rear again, although with a non-machined flange face against the mounting plate. Looks inelegant but does the job. I like the idea of the adjustable pushrod though. That allows one to choose where the piston ends up in the s/c bore. It seems pretty clear from the measurements Marco has posted that we don't need anywhere near the full length of the bore to accommodate full travel (even with a .75" m/c), so no problem there.
BTW I'm a fan of the self-adjusting clutch. If we didn't have it then the pushrod would have to be adjusted to compensate for clutch wear, rather than a simple fluid top-up. I suspect that excessive linkage wear and incorrect s/c being supplied/fitted may be behind the need many of us have had for an adjustable pushrod.
Cheers,
JC -
10 hours ago, Tim D. said:
You are correct, reducing the diameter of the master reduces the amount of fluid displaced by the master and hence reduces the distance the slave moves. In my hands a 0.625" does not move enough fluid to disengage my Saab 900 clutch. The way to solve this (which I did) is to increase the distance the clutch pedal pushes the Master cylinder. This is where the adjustable push rod on the pedal works. In a TR6 if you lengthen the pedal push rod the pedal itself moves back towards the driver. This has the effect of increasing the "throw" of the pedal and hence the distance the pedal moves the pushrod and in turn the clutch master cylinder. This displaces more fluid and moves the slave more disengaging the clutch. It is one of those things you have to work through in your mind.
Lengthening the slave pushrod could in principle produce similar effect by preloading the throw-out bearing against the clutch cover so less movement is needed to release it. But it is a bit too much like riding the clutch and to me would increase the wear on the throw-out bearing and the engine thrust bearings.
Thanks Tim (and Marco). That all makes perfect sense. I hadn't thought through what the effect would be of the pedal-m/c pushrod. And it sounds like it may well be worth experimenting with a smaller m/c anyway. I have already gone through all the normal wear points to reduce play so I may have travel to spare.
Cheers,
JC -
On 12/29/2023 at 1:29 AM, Z320 said:
And the adjustable push rod is not really needed if the clutch worked before…..
Hi Marco,
Is that correct? If you need 30% less force, you’re going to get 30% less travel at the slave cylinder for the same pedal travel. From what I’ve read elsewhere (e.g., Buckeye Triumphs) I thought the slave travel was marginal, so reducing it by using a smaller m/c would cause problems with disengagement. Would be great to know otherwise. In that case I’ll order a smaller m/c straight away!
Regards,
John C -
On 12/29/2023 at 7:40 AM, Tim D. said:
an adjustable push rod between the pedal and master cylinder
Why not between the slave and actuating lever? Isn’t that much simpler?
Cheers,
JC -
2 hours ago, Z320 said:
Best with this trunnions is to use anything regularly
Now that is good practical advice
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On 1/2/2024 at 2:41 AM, Jonny TR6 said:
Was quite surprised to see such a vacuum, however thinking on it, with the link rods disconnected, there’s nothing to stop the cylinder vacuum pulling the butterflies open, as the return springs aren’t super strong.
More likely simply leakage around the burretflies. It’s unlikely the cylinder vacuum will do anything as it (and the upstream air pressure) act equally on both the upper and lower semicircles of the butterflies. So that means your butterflies are not providing an equally good (or poor) seal when closed. If you’re looking for the best response when going from fully closed to open throttle, then your goal is to get those numbers as equal as possible. It’s very hard to balance butterflies *within* a pair but you may have some luck with a tiny adjustment to 3/4 to bring them closer to 1/2 and 5/6. I found that to balance within a pair I needed to use the technique Andy (I think) mentioned - snap shut when the screws are slightly loosened - and to twist the shaft slightly. But the latter was guesswork and the result may have been wishful thinking!
Hope that helps,
JC -
On 12/18/2023 at 9:22 AM, BlueTR3A-5EKT said:
You sure the bush sits in the back of the crank rather than in the flywheel?
Aaah. Yes. I knew that...! But I had totally forgotten, so thank you for reminding me. The bush was indeed in the flywheel (removed for machining), where it had been the whole time. Sorry for wasting everyone's time!
JC
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On 2/2/2022 at 3:31 AM, iani said:
Thanks Harry, I remembered I have a spigot bearing in the garage.
Hi @iani
Any chance you know the dimensions of that spigot bearing? I need to get one and the one that came in my clutch kit isn't the correct size.
Thanks,
JC -
Hi brains trust,
Can anyone please tell me the dimensions of the gearbox input shaft spigot bearing? The one the sits in the end of the crankshaft. No idea how/why/when, but my car lost its along the way somewhere. The new one that cam in a clutch kit is the wrong size, hence this question. 1971 CP car, FWIW.
Thanks,
JC -
16 hours ago, mleadbeater said:
I would consider looking at using a vacuum bag for this type of job, it would get over clamping issues, and should flatten the usual rippling if using burr veneers
...or possibly using hide glue / hide hammer? That's probably how the veneer was applied originally. Mind you, it very much depends on how the curved/raised bits are veneered. The hide method is easy on flat surfaces and requires no clamping or bagging.
JC -
Hi Andy,
Is it possible that the mechanism is giving full fuel enrichment but not full idle increase? For instance if, when the enrichment lever hits its stop, the fast idle cam has only rotated part way. Or if, with everything closed, the fast idle cam is already partly rotated. In both cases the cam can't achieve full travel.
I also have the Fred Millturn choke arrangement. From memory I started with the fast idle cam, getting the clearance right with it fully closed, and only connected the fuel enrichment once that was done. I can't check just now, as the car is in bits, but I seem to recall that getting both full fast idle and full enrichment was not possible. I did consider going back to the original setup. I got it working eventually.
Good luck,
JC -
18 hours ago, Andy Moltu said:
As has been pointed out things like braided injector lines can result in vaporising in or near the injectors which compounds the issue.
I think this may be conflating two issues. One is the fuel vaporisation upstream of the pump (well covered by others in this thread). The other is fuel vaporisation caused by heat soak along those braided lines with the hot engine stopped. When you try to restart there's a lot of injector line priming required. The clamps holding the injectors into the throttle bodies are the likely path of heat conduction to the braiding via the injectors, unless of course the PI lines are in direct contact withe the engine elsewhere. It's not about heat absorption by the braiding from the ambient under bonnet temp, it's heat soak from the cylinder head via a metal pathway.
Perhaps somebody could test this by grasping the braided line after a long run and a 10min rest? I'm happy to do the same with my original nylon lines...
JC
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Might be cavitation, particularly if you have the original Lucas pump (and if it hasn't been reconditioned in 50 yrs), but it may equally (or more likely) be fuel vaporisation in the PI pipes between metering unit and intake manifold. You haven't got braided fuel hoses, by any chance, have you?
But in answer to your question, cavitation occurs in the pump when the pressure drops below the vapour pressure of the fuel. That could be caused by high temperature or by a restriction in the fuel supply to the pump, or a combination of both.
JC
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Those look totally the dog's b**ll*ks
Shame I have centre-lock mini lite lookalikes. How about TR6 wire wheel spinners? Eared, perhaps?
JC
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...and here's what Overdrive Repair Services say:
QuoteOriginal literature has said the Healey gearbox and overdrive should be using a mineral engine oil. However, the exact same overdrive on a big Healey will also be fitted to a Triumph – which also states to only use gear oil.
If you would like to use a mineral based oil, many experts agree that brass syncro gearboxes should be using engine oil. This is only before some mineral gear oils have additives which may corrode brass syncros.
When using engine oil, avoid using a ‘friction modified’ engine oil. As the syncro cone relies on friction to operation, if the oil is too slippery (‘friction modified’) the syncro is likely not to work. This is the main factor of why people choose to use a mineral engine oil which doesn’t contain friction modifiers.
So really you have quite a choice. I had problems when I had a recon OD (from ORS) fitted and filled with GL4. Swapped to engine oil (Penrite HPR30 20W-60) and haven't looked back for the past ~10k miles.
YMMV
JC -
On 8/1/2023 at 11:25 PM, TR NIALL said:
I’ve a rough one I already sprayed with Matt Black paint after stripping the Veneer off and it looks OKish,I find if you put something shiny and new with in the Car you then have to start replacing everything else so it then becomes an expensive exercise,I’ll stick with rough and ready.
BTW I done this about 8yr ago I don’t like rushing into things
Any tips on removing the veneer? Did you sand it or is there a simpler way?
Thx,
JC -
19 hours ago, Malbaby said:
Seems I would have to pay for a local engineering shop to allow me to video the bad runout problem with the balancer on their lathe....Not keen to throw away anymore money at this.
Is there a Men's Shed local to you? If they have a lathe I'm sure it would cost you nothing. I know my local one has a lathe, 'cos I gave it to them
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Sean,
This thread is your friend. From @bat10man back in 2006... It's what I installed. The inline test point makes removal very easy. I did a quick check and the part numbers have been superseded. New ones are:
Gauge 63mm 0 -10 bar back entry R.S part number 136-5223 cost £25.20
Inline Test point R.S part number 432-5498 cost £13.87
Microbore hose 1m long R.S part number 432-5656 cost £24.83 - other lengths available.
John C
Mystery flat spot
in TR6 Forum
Posted
What power are you seeing at the rear wheels?