DanMi

to tell if it is wiring just put the car into 3/4 flick the OD switch and listen for a load click from the right side of the box, i.e. the solenoid if the cover is off you can put your hand on it to feel it energise check that it is adjusted properly so that the holes align when energised 1/8" drill bit. Also check the oil level. All simple things to do before deciding to take the box out

how long has it sat? could it be simply old fuel, my spit ran terribly after lockdown when it hadn't been used for a long time until I refuelled it

If the valves were not closing the gases would exit via the manifolds not the rocker cover. If there is excessive gas coming from the breather, that would indicate excess gases entering the crank case, maybe worn/broken piston ring. I would do a compression check

As far as I know the MK3 left the factory without seatbelts and they were fitted by the dealer post 1968 as standard (optional before), the MK4 had them factory fitted so I would doubt them having been fitted to use up stock as the factory never fitted the Britax Excelsior ones so would not have had stock. I would suspect they were changed later

My last modern an x type jag diesel estate had a bolt to a rear suspension arm that had a bush that failed. but the bolt was fitted at the factory before the subframe was attached so could not be removed without removing the diesel tank and supports or the whole sub frame. Most cut the bolt, ground off the captive nut on the other end and fitted a bolt from the other side. Only an issue on the diesel estate version but they only need to fit the bolt from the rear not the front to make replacement easy

Fuzz also said that there were only about 20 MK1s left, obviously looked on howmanyleft.com for spitfire MK1 of course very few were ever registered as MK1 as that was never used until the MK2 appeared. there are many more than 20 left

I had a problem getting my spitfire pump to work, a second non return valve after the pump sorted it out. The bellows is just a rubber bag, unless leaking there is nothing to fail, but then it started to leak but early spit ones are available

for heavily rusted components, I have successfully used cheap brick cleaner which I believe is HCL works very well, but it flash rusts fast after

Yes overrider bracket. There should be a metal tube and a long bolt which hold the top of the rear overrider on the low bumper cars https://www.canleyclassics.com/?catalogue=triumph-gt6-mki/ii&diagram=triumph-gt6-mki/ii-bumpers-mki

The colour of coolant doesn't mean much at all any more, some can be had in multiple colours so you really have to go by the chemistry. Penrite do a blue longlife OAT https://penriteclassicoils.co.uk/product/7-year-blue-coolant-anti-freeze-premix/#:~:text=Penrite 8-Year Blue Coolant,degredation of the cooling system. but it can also be pink green etc depending on manufacturer

manifold vacuum would be highest when the engine is at high revs but throttle closed, so as Johnny says on overrun

no the mainshaft is different

If you replaced the throttle disks it is very easy for them to not be perfectly centred and so allow air around the edges, If you hold the carb up to the light and can see any light around the disk it is not centred

the endfloat is basically how much the drive gear can move up and down with the pedestal fitted. You adjust the number and thickness of gaskets to set this movement. The Haynes way gets you to measure the gap with no gaskets if that is say 10 thou then you need to add 15 thou of gaskets to get 5 thou endfloat, they get you to measure by cutting a notch out of the gaskets so you can get a feeler in to measure the now 15 thou gap you could also use a dial gauge and a strong magnet to pull the drive gear up to measure endfloat and just adjust the number of gaskets until correct

Probably won't help but I set the endfloat when I had the sump off (complete rebuild) with a dial gauge on the top of the drive gear and then pushed up on the oil pump drive from underneath. Very simple but not helpful if the engine is complete

The bottom line is the factory specs are for what the endfloat should be at rebuild. This will of course increase with wear and after some time will be out of factory tolerance, but factory tolerance is for a new engine, so yes if I have the engine in bits I would set within factory specs but on an older engine a few thou outside is to be expected

I think they are just cheap nasty connectors. i just use the proper lucar type with separate insulation as per original

From what I have seen they are more than a few thou over before they fall out, 3 thou over means that they are wearing and need to be monitored

there is 2 on ebay at the mo. They do have the TR tax though! https://www.ebay.co.uk/itm/404795454038?itmmeta=01HPPTSJ8FDMMJ2P07CGYPCBCS&hash=item5e3fb07256:g:mHcAAOSwk0tlV53b&itmprp=enc%3AAQAIAAAA0Gb9LHOOxo%2FLwvAy1YdL01AeHeX2Y%2Fs%2Fp6t8KlNKqU2x8udeWSIiwdmySwRJBWXFT5Jv4A5JNCz7ac20prCdDZR%2FO6n5ollvlzhl4LrAxzulYnU2%2F3rc41A4OPunxeEqaBpZAodOewfdwimFdJnlQBrpoqbHOJzWtRlTDnWZEVrMJ9CuK%2FZ0bFbRyYPGHB81vz72Wtjdy8nsF2vsn1eD5oDifeS2A7J9MfNzYRnGAW6BviGDIZbi%2FqpjYoFyUiaLvdn6olAtjh9sLf2mCEKVJAc%3D|tkp%3ABk9SR6qk5tq1Yw https://www.ebay.co.uk/itm/256276578620?itmmeta=01HPPTSJ8FKNJBY3B5CSQGWK5W&hash=item3bab46413c:g:XgUAAOSwiKFlQQRt&itmprp=enc%3AAQAIAAAA0I1IFH%2FlovHnYZwde53DItuHpcGdcyYW%2BWOiI1grFXRohhy%2BpYJ3ugmU5BQrDmGj3HXBVQvSF9CxD%2FjRZUIMBiAt6mD%2F82%2BBMEEIwd%2Bg0MnMyvm4FZ%2BT0Kp0g8nXvEOhAy8UqQfh8m8IfLERcNiJvR7TfsSFSi4HVfJYcBIbJld%2FoAvk2V%2BrRifm%2FZHrYAK6X3Fet2wd83TtCLtG0fnSQ73Fc0tBESX5Vt87Oc7T08CuBAyNAcfuuKTFMF%2FtP0dlYy8%2B7TqyJauiRBfCcV6mFb8%3D|tkp%3ABk9SR6qk5tq1Yw

It wouldn't be just the capping, the early frame would not have the holes with the catch in into which the later soft top catches fit I also have a suspicion that the hardtop header rail bolt holes were at a different spacing on late cars to early so you need to check that the spacing of the mount holes in the frame matches the captive nut spacing on the hardtop of course if not you could use rivnuts on the hardtop

probably the aluminium push rod tubes, which are a pain to seal, oil leaks slowly and collects at the back. My mk2 spit did this but maybe not if the oil is collecting on thee rocker box as too high

that is sitting too far back. I am not familiar with early mk3 but the metal at the front should not be behind the softop clips as it is in pic 2, the whole thing needs to move forwards. Try to put a bolt through the mount hole in the frame and align with the captive nut in the hardtop header rail, that will show you where the front should sit

there were various brake master cylinders used over the production run of the small chassis cars. The clutch was always 5/8 diameter as was the brake in most cases (late GT6 was 3/4 I think) Some brakes had an angled reservoir, some didn't, early spits were tall others fat. However so long as the bore is correct and the reservoir big enough it doesn't technically matter

or is it that the switch is too short?

to get 20-30 more bhp would requiree a full engine rebuild with gas flowed head, high lift cam etc. New carbs and exhaust might give 5bhp. The twin exhaust will probably be more of a placebo as the louder note will make you think it is faster