johny

The idle revs of course will be higher on choke but then drop when warmed up and the knob is fully pushed in however I assume this is something else youre experiencing?

Wait a minute though, if theres air in the system this compresses as the engine warms up so the radiator cap doesnt have to lift to relieve the pressure generated by the expansion of the coolant. This is how some Triumph models avoid having a reservoir bottle because you leave a gap at the top of the radiator which absorbs the expansion instead of pushing coolant out. However in the GT6 there isnt space in the rad to do this so it must be full and have a bottle....

Have you confirmed the reservoir bottle level goes up by approximately 50mm from cold to hot Kevin? If so then the system isnt being subjected to anything more than the 13psi of the cap and the hose must be weak...

Yes the overflow pipe has to be strong enough to resist a slight vacuum as it sucks coolant back into the rad however clear pipe is best as you can then verify that it is always full of coolant and air is not getting in somewhere...

I think the quality of the application made a big difference as well - some technicians just did the easy, obvious bits and signed the car off....

Yes mine has blocked on more than one occasion but I have an after market aluminium radiator which has a tiny overflow pipe. Cant say Ive ever had infated hoses though😮

Its just really strange that you have hose inflation as they should easily withstand any pressure in the system up to the radiator cap lifting (13psi max?) without distorting. So either they are very poor or youre exceeding the radiator cap lifting pressure somehow...

Let us know the outcome as the sign of a good company is how they deal with issues....

Have a look at the overflow pipe of the radiator and poke a piece of wire through to ensure its clear. This connection must be open to atmospheric pressure via the overflow bottle as if not the coolant in the system cant escape during warm up (even though the rad cap lifts) and as liquid is incompressible it will try to burst hoses or worse...

I wouldnt blame yourself as you shouldnt be able to cut through a hose with the jubilee clip. The replacements these days seem to coming made just of a very soft rubber with no reinforcing - the originals were like elephant hide...

All we can say with certainty Steve is that a non overdrive single rail gearbox is 3 inches longer than a 3 rail non OD. If your car was standard it would have had the latter so be aware that changing to the new gearbox is likely to make your new engine sit further forward. I dont think this will affect the gear lever position and also if the propshaft has a sliding joint you should be able to reduce the overall difference...

In the Vitesse wiring diagram the in-line fuse does front parking, tail and number plate lights while flash has a separate feed from a main fuse👍

Even when a 1500 came with a three rail gearbox it had to have the bigger 7.25 clutch so I can never see there being a part number thats common to a Herald!

Ok well if you can confirm that reverse is on the right then Im flummoxed🤔

Paddocks part numbers look same as Rimmers and theres quite a price difference between the two different sized clutches. Im beginning to think you have a 3 rail gearbox as Ive described and maybe even a 1300 engine...

According to Rimmers clutch kit part number GCK160P is for Spitfire/Midget 1500 and GCK272P for 1360 Herald. The 1500 should have a bigger 7.25" diameter clutch because of the extra torque it produces while the 1360 has 6.5" unit. Perhaps yours has already been converted to a 3 rail gearbox with smaller clutch rather than the usual 1500 single rail - the former has reverse gear selected by pushing the lever to the left while the later gearbox reverse is on the right?

Its difficult to know Dave whether carburation problems come from higher engine temperature or high under bonnet temperature or both as most likely theyre connected. Either way you need to do some thing about it and in my case the only measure Ive taken is to replace the mechanical fan with a decent electric fan which keeps the engine temperature down and additionally moves more air under the bonnet so whatever the cause was I now dont get carburation problems....

Has the rocker shaft got to come off anyway to get to the head bolts on a mk2?

They should have painted them green though😂

Out of interest will you be retorquing the head after a few miles?

Did you check chain wear as per the manual? Sprockets dont look bad but new chain will wear rapidly to suit them....

No, I believe the A frame referred to is a towing arrangement where all 4 wheels of the car remain on the ground as the frame itself has no wheels...

Yes non OD single rail boxes are 3 inches longer than their 3 rail equivalent. Thats probably too much to accommodate with a standard propshaft so a non OD Vitesse propshaft is the only other standard one that would do the job. However this has a different flange for the diff but that could actually help as with a 1500 engine it would be nice to have the 3.89 ratio diff from the Vitesse as well. Though then the last sticking point is that the Vitesse diff has different output flanges so wouldnt match the Herald half shafts but luckily the two diffs quarter shafts can be easily swopped over and you can finally drive off into the sunset😊

However, although not ideal, the majority of the bearings are accessible from under the car with the engine in place...

Excellent now if you can just get the plastic radiator overflow pipe to stay full all the time (assuming the bottle has sufficient in it) your cooling system will be working 100% correctly....