Ian Foster

Clearly a bit of thread drift from the original subject post, but my 2p’worth in any case. I think experiences with silicon fluid can vary and may be dependent upon the material/quality of the seals fitted. I have been using silicon in brake and clutch systems since rebuild in 2011 (for the usual reason of wanting to protect my new paint) and whilst this has been apparently problem-free in the brakes, I have seen fairly rapid degradation of the seals in the clutch system as evidenced by black staining in the master cylinder and accumulated black sludge in the slave after quite a short period. The clutch obviously works the seals a lot harder due to the increased range of travel in the cylinders and silicon is reported to have reduced lubrication properties compared to traditional glycol based fluid. I would also say I have been surprised at how soft rubbers exposed to silicon can become. As part of a general overhaul of the clutch system (long story) I have had my original 1” Girling clutch slave cylinder stainless steel sleeved and re-rubbered by Past Parts. They use seals made in the UK by Nelson Stokes (Cornwall). Correspondence with Nelson Stokes produced the following helpful response in respect of use of silicon. “Thank you for the enquiry I can’t comment on other suppliers but all our seals are compatible with silicon fluid but we do use two different materials one being SBR and the other EPDM. EPDM is the better material to use for this fluid but both are compatible”. Clearly this is helpful but not definitive and I have decided to revert back to Dot 4 for the clutch only at this stage and will be happy to report results in due course. As a general comment, I too am of the mind-set that I would generally be happy to pay more for improved quality as I think many others are. Ian F

I have two 11/16” ARBs. One is the original from my 1969 GT6 Mk2 the other is off another rotoflex GT6. When laid on a flat surface, one has set of about 10mm, the other 15mm. The o/s is higher in both cases. There are few minor inaccuracies in the bends on one side of the bar, but this is a feature of both so I am assuming this is related to the original manufacture. The 7/8” bar (off a late Spitfire I think) that I currently use is almost flat. I changed to a 7/8” bar years ago to try and address excessive rear roll, but I have since stiffened my rear spring by the addition of another central leaf and the rear end is much better as a result, so I’m considering reverting back to the original 11/16” bar to reduce understeer. I drove Nick’s Vitesse EFi which runs a standard bar and noted good turn in, with similar front springs. I have tried to cold straighten my original bar by clamping to a bench and bending with tube without success. It does twist a long way but does not retain it and having tried this I cannot believe that a bar can acquire a set ‘in service’. I assume it is a special spring steel bar, so can it be heated and bent without affecting the steel, or if it is heated does it need to be quenched/not quenched? The other alternative unless I can be convinced that the set is a good thing, might be to have adjustable links, which could be done with rod ends (expensive) or cutting, threading and joining the linking rod on the original links with a sleevenut and locknuts. I have some recent NOS links that are in good condition. This link allows comparison of different bar diameters https://balancemotorsport.co.uk/suspension/anti-roll-bars#cal PS Similar thread running on Sideways forum. Ian F

Hi Guys Thanks for the input so far and a Happy New Year to all. The engine has gone back in as it was previously, using the same good condition mounts and same spacers.The front engine mounts would have to move significantly to move the pipe laterally by 3/4" and there is no lateral movement possible at the rear mount which is a bit of a special for the J type O/D. The engine and box slotted back into position very easily, so I'm thinking the down pipe must have always been like this which would seem to explain why the front pipe of the centre section has a kink. The down pipe is actually a pattern part dating from circa 1980s, when you could still go into Thicktwit and get GT6 bits. The flange connection only allows very slight rotational movement. Perhaps this kink 'feature' is to allow access to the overdrive pump/filter. As I am intending to have a new downpipe made as per the above, I have the option to get it onto the centreline and will probably pursue this course, based on my current geometry. Ian F

I currently have the exhaust system off my GT6 Mk2 after an engine out clutch change. My current exhaust is a bitsa, comprising a standard mild steel downpipe, a mild steel Mk3 centre box (chopped at the rear end) and a stainless wheelbarrow rear section. It sounds good and is not at all boomy, so the combination is actually working well. A stainless 6-3-1 manifold is a future project, either waiting for someone to offer a good one commercially or for retirement and development of sufficient skills, equipment and energy to fabricate my own (could be a long shot that one !). As a stopgap I would like to replace the existing downpipe with a new stainless item, as it has multiple crush bends which would appear to be an unnecessary restriction. The systems on offer from the usual culprits also seem to have even worse crush bends, so I’m considering getting something made from mandrel bent tube, which should hopefully be a relatively straightforward job for an exhaust fabricator, with the existing one to copy. Jetex make a round ‘bomb’ type silencer which is similar to the original centre box but is a straight item, which would fit nicely between the rolled edges of my chassis and plug straight into the rear section. However, looking at the way the existing down pipe fits, it is apparent that the rear of the section which finishes just in front of the small cross member, is not on the centreline of the chassis (photo attached). The front pipe of my existing middle section has an offset kink which would appear to bring the centre section onto the centreline, but it is a bit close to the chassis at the join. Is this the standard set-up and if so why would this have been done? If I'm having something fabricated I can get it altered so it comes on centre (about 18mm towards centreline). Could anyone with access to the underside of a GT6 Mk3 have a look at this area and let me know what theirs looks like. Cheers Ian F

Ian You didn't state what carburettor it is for, but I have one on a spare 175 CD-2 which measures 69.5mm overall. Let me know if this is of interest. Ian F

I'll second that. On my GT6, 7"Cibie H180s + Philips vision plus bulbs are amazing. I know the Vitesse has 5"? units but hopefully there are some upgrade options. Ian

Cibie H180s, Philips VisionPlus bulbs and relays = awesome ! BBQ'd roadkill anyone ! Ian

Hi Nick I have the lip type seal on my Mk2. I thought it was OK until last night until I realised that the top section of the seal (ie along the hinges) had flipped itself inwards. I have held it the correct position with some temporary gaffer tape and shut the hatch to try and 're-train' it. Please keep us posted on your investigations, as I think I will have to replace mine eventually. Ian PS Pleased to see you back in the garage where you belong !. PPS -Also posted on Sideways

Hi Guppy Propshaft Services in Feltham, shortened and balanced a non OD shaft for me in about 1980, when I converted my GT6 to OD. It's still on the car today about a 100k miles later, so they must have done a good job !. Ian F

Wayne Totally agree, it is one of the worst jobs on a GT6. I have followed a similar path with hoped for bullet proof components, but have still had to take it out on numerous occasions to fix bl**dy stupid things like cr*p gear lever spherical bearing etc. (one on the eve of the RBRR having put in a new one only 150 miles before). It not just the tunnel cover, its the dash centre, the radio, the dash support and getting the tip of the tunnel past the lower vent hoses is always a real battle. These were a Mk2 retro fix, so no wonder it's all so tight down there. The guys on the Triumph assembly line must have been contortionist midgets ! I have seriously considered a removable section at the base of the gear lever (albeit I think I now have a reliable gear lever bearing) but so far haven't actioned anything as the last time I had it out, I just needed to get it back in quick. I share your pain. Ian

Fiited on the GT6 with good results....as Nick says not hard, but you will need a dial gauge to set end float Ian F

Thanks chaps Gives me something to dwell on. Ian F

I have had mu Gunson one for over 40 years. Just as simple gun with no adjustments, which is fine on the GT6 with its graduated crank pulley. It does show whether the distributor is advancing with revs, which is something that a static time only cannot. I would recommend however that to confirm that your crank pulley is accurate ref TDC, which can be done using a piston stop. Mine is about 1-2 degrees out (found out when I was checking valve timing... which was spot on by the way and reassuring after an engine rebuild by others) I also picked up a dwell/rev meter at Beaulieu AJ a few years ago which is also useful as a' second opinion' on revs. PS has anyone had experience of setting points using a dwell meter? Ian

Richard When I first fitted the Huco pump, I kept the mechanical one in place with the delivery pipework (just in case), but have now removed it and blanked the mounting onto the block. The mechanical pump did make a sort of chuffing sound as it was trying to pump air...poor thing! I could always carry it as a spare part, but probably won't as I think the Huco is good bit of kit. Ian F

Paul I have it in the engine bay, bracketed off the front face of the n/s suspension turret, using existing bolts. So I can't hear it at all above the engine noise, except for the tick-tick, gurgle-gurgle when you first switch on the ignition (or ign + aircraft style isolator switch in may case). Ian F

I have a Huco puller on my GT6, for all the reasons Nick gives. Has been excellent with no re-occurances of fuel vapourisation. Ian F

Hi Richard You should try and get the system as clean as you can, so flushing a chemically cleaning are the top priority. The whole drain tap can be unscrewed which will give you a 1/2" diameter hole to poke through. Stiff wire (eg coat hanger) and a robust cable tie can be used. I have cleaned with Holts Speedflush (single part) and the two part product. Follow the instructions and you will be surprised how much crud will come out. Heater valve open for flushing and refilling. I would keep your existing sender for now, just so that you can monitor whether the cleaning has made any difference. does sound as though your water pump may be past its best and they are fairly cheap to replace. Happy flushing. Do report back. Ian F

Nick 3rd and 4th gate stiffens up slightly on my 3 rail box as it warms up. Nothing drastic but its there. Pulled the remote off to check as you have done, but nothing obvious. Will be interested in your further investigations/analysis/findings as always. Ian F

Aiden The list of checks is certainly growing and it looks as though you are going to have a busy weekend, but it pays to be methodical and thorough. In my experience with float valves, if there is problem it will usually result in the carbs flooding due to not being able to shut off the fuel, in which case fuel will be flowing out of the breather hole. It is possible to remove the valves for cleaning or replacement with the carbs in-situ. You will need to remove the float bowls (make sure to undo all of the screws) pulling it down to get clear of the jet bushing screw (the big brass bit). Be careful not to twist it to much as you might damage the float. The float needs to be released from the pivot and the float valve can then be removed. Clean in carb solution and then check that it closing properly by blowing through it whilst touching the centre pin. Before refitting I would pump a bit of fuel through with the priming lever on the pump which should flush out any debris in the lines if present (collect it in a container and have a look). Refitting is reverse of the above ideally with new float chamber gaskets. Regarding mixture there is no reason why the mixture setting should have changed since last year when you reported it running OK, so I would leave that alone for now. There is a test described in the WSM involving slight lifting of the air valve that should be used to determine whether any adjustment is required. If the car is not running right at present, the plugs will be a poor indicator. (luckily you have the carbs with the easily adjustable jet. I have similar but in CD175 flavour) Is there anyone in your local area that can offer practical or moral support. Further reports awaited with interest. Ian F

Aiden That's the diaphragm out of the Smiths breather valve (looks OK by the way) I actually meant the carburettors diaphragms, which you will need to get at by unscrewing the tops of the carbs. Should be fine if only three years old since rebuild, but you never know. (watch out for spills of dashpot oil and be careful not to bend the needles-diaphragm will only fit in one position on reassembly) Another one to add to the list is dashpot oil, as this is partly controlling mixture (richening) during acceleration It doesn't sound like fuel vaporisation to me. My experience of FV is the engine dying when it gets hot in traffic or not restarting when left after hot running. I my case when it happened, taking the top off the pump I could see the fuel boiling the base of pump. Reassembling the pump and bleeding out the vapour at the carbs allowed normal service to resume. (now finally 'cured' with a Huco electric pump - I hope) I think I would check these fuel items and then concentrate on the ignition bits as above ie:- cap, rotor arm and coil. Do try it with your emergency set of points and condenser, it will be good practice in any case (I had to do it once in anger after 'failing to proceed' off the ferry at Portsmouth, which was annoying as we had been all the way to Florence and back without any problems). Also check the timing as well with a strobe and that it is advancing when you rev it, as balance weights in the distributor can stick. Hope this helps, please report back as you work through the list...and don't change everything at once otherwise when you fix it you will never know what the problem was. Ian F

Aiden So (new trendy way to start every sentence), when you have misfired and jumped your way to 40mph and it settles down, if you then let the speed drop and then accelerate again, does the problem reoccur ?...if so then something doesn't like being on load. Does it idle OK ? Clearly it's either fuel or ignition as long as nothing else has changed. On fuel side I would check that:- tank outlet is clear (floaters in tank blocking outlet) pump filter and any inline filters are clean breather is clear (not sure there is one on the Mk1/2 as I think it vents through the cap carburettor diaphragms are OK carbs are synced On electrics side (I assume Delco distributor):- No experience of H&H Ignition (sorry) Have you tried putting points and known condenser back in (I did this when my ancient Mobelec E/I failed and it runs really quite well with a Shacktune external motorsports condenser) Rotor arm (Accuspark do a red jobbie for Delco) Distributor cap (TD Fitchetts have original Delco caps) Try a coil swop PS others will be along soon. Ian F

Aiden More symptoms please. What's the spec of your ignition system ? Points and condenser or electronic, plug make and number , leads, coil etc. ? Ian F

Paul Sounds as though you have cracked it for now. Just watch out that RSPB don't catch you. So in summary is your solution the spring on the pushrod and the spring on the lever? Pete Are we confident that the release bearing is supposed to spin all the time. Is there a reference source for this ? Ian F

What Nick said ! I have just had mine done and so far so good. (in Poole, Dorset) Stainless steel nuts have gone a fetching shade of light blue, so yes it does get hot ! Ian F

Make sure you road test with the tunnel out , which will be really nice a cosy with the current temperatures !! You wouldn't want to put in in and then take it out again now, would you ! ( I hate that job too, but with a mate we have got it down to quite a fine art), a good job as we had to good in in fading light on the eve of the RBRR to change that stupid plastic ball at the base of the gearstick-now bespoke Delrin one) Hope you have sorted it. Will look forward to your report. Ian F