The 1973 Triumph Stag Rebuild

May 2016:
Sorted all of the parts in the Mk2 Blue car, some engine pieces with a block (which I now know is the original) that has nice bores that are at +20 thou and a crankshaft that has iffy bearings, but is only cut -10 thou so thats a start. A good starter motor, great s/s exhaust, 12-vane water pump. One or two AC parts, but not sure if I'll bother with that. A nice looking gearbox with no damage but I would really like to go to an OD, which really should be a J type but with the parts I have an A type maybe make more sense.
The body is in fine shape with the exception od the rear seat pan and the area around the transmission tunnel/firewall where some animal had attacked it with a lump hammer, presumably to fit a different gearbox.. Then they cut the crossmember!
I'm awaiting arrival of the Mk1 sparees car, keeping fingers crossed on the heads!

June 2016:
The Mk1 is here and what a sad sight! I was a bit worried about the engine but once it was removed and the heads taken of (after the required 2 days to remove the single stud that I could not budge) I had a pleasant surprise.. Heads look great.. I just need to work out of they have been skimmed but it looks like there is still some meat there. In general the engine seems in good condition, and was probably rebuilt before the cars demise. It turns over fine, The block is OK the crank is great. The timing chains and tensioners look new and best of all the aluminium around the head waterways has not corroded at all. All engine parts are there but little else.
The transmission tunnel to firewall area is Ok except at the bottom and the crossmember is fine so I plan to cut them out to help with the repairs to the Mk2. Unfortunately the rear seat base and seat pan is toast so I'll need those eventually.. Plus the fuel tank is not great and I was hoping for that as the one in the Mk2 has been modified.

July 2016:
Where to start? Well the instruments looked a bit sad so opened them all up, glass beaded and repainted the interiors and cleaned the faces as best I could. The speedo and Revcounter are fine but the other 4 are not great. 2 of them are not standard, the Mk1 has different types. I got hold of some from a 73 Truimph TR6 and they are the right type, even included an Oil pressure gauge. The faces were OK except the oil pressure which I touched up a bit.

August 2016:
The wooden dash pieces were there, but some were delaminating and the veneer was not great. I decided to have a go at re-veneering and after fixing as much of the delamination as I could with epoxy, and making a center console piece from scratch I reveneered with some Cherry, and after a stain and a few coats of water based varnish I think they will be fine..

August 2016:
Rebuilt the heater A/C unit. I decided that I would loose the old 70s A/C components except for the evaporator in the heater box. That way should I ever decide to go with a Modern A/C system at least that is there. I cleaned and tested the evaporator with a pressure check and vacuum down, it seems fine. I removed the TXV and plugged the hoses, then filled it with nitrogen to prevent any corrosion. The heater core was also tested and seems OK as well. replaced most of the pop rivets with screws to make access easier next time, (which I hope is never!) All flaps were checked and new seals inserted. The A/C thermostat is shot, but if I ever go with A/c It will just be an On/Off affair anyways. All of the vacuum componenets seem Ok but its difficult to say at this point. I found out that the A/c Model has a special 3 position fan switch that is not listed anywhere, and I do not have one.. more on that later!

Sept 2016:
Started on the carbs which were a bit worryingly furry, but they glass beaded up fine. The carb rebuild tech info on the buckeye triumphs webpage is a wonderful resource. All of the gaskets were replaced, the bypass valves were repaired and the compensators cleaned up and adjusted using hot water. The needles look fine so they will stay for now and I can make that call once I tune them up, a while away yet!

Sept 2016:
Got my hands on a J type Overdrive from a TR6 but it should provide the parts to rebuild my Stag box. 1st gear is stripped but the rest of the parts look fine, nothing nasty seems to have got back to the OD unit. I had trouble with the OD being "spline locked" and it would not pull off the main shaft. A Volvo site provided a way to release the splined by removing the sump and prying the clutch carrier back whilst spinning the output shaft.. it worked as the OD then popped off easily. I found that to convert to J type I would need a special rear gearbox mount, which I purchased in the UK, and different exhaust downpipes, which I will worry about later!

Nov 2016:
Finished rebuilding the Gearbox, used all of the Stag parts as they are stronger than TR and just added the Overdrive. The sliding clutch was a bit worn so ordered a relined one from the UK. All went together well and the Overdrive kicked in fine when tested. As I did not have the cover with the 3/4 gear switch I had to modify my original one, its just a matter of drilling a hole and thread for it in the exact centre of the boss, I then had the machine shop machine it down a little to get the switch at the correct height.

May 2017:
Over a year now, some big progress but not much to show for it. The heads are back from the Machine shop, they look OK and do not appear to have been skimmed too much. I redid all of the clearances and needed some extra shims. I found that Lotus and Saab shims work, plus they have some sizes that are thinner than Triumph ones. I needed to fix the threads on 3 of the spark plugs, they may have been ok but its so much easier to do this now. I used helicoil brand Spark plug inserts with hi-temp loctite, which went well. I also repaired a few threads with regular helicoils. I also refurbished the steering column, rebuilt the Power steering pump and with my newly aquired glass beading cabinet prepped and painted everything I could lay my hands on. My attic is straining -- 1/2 the car must be up there now!

July 2017:
I stripped most of the trim off the car and its OK but some pieces will need replacement or rechroming. Have been making a body rotisserie from a pair of Engine stands, with some wheels on it so I will be able to move it around in my small garage. The engine is finally back from the Machine shop. The first block was done and during assembly I found that the main bearing caps were so off centered that torquing any of them down siezed the crank. I had asked the machine shop to fully check the block over before starting (I had another!) but they apparently did not bother with that, you could tell by just running a finger over them. I also gave them 2 cranks and asked them to pick one to do, For no apparent reason they picked the rusty one and it came out with quite a few pits in the bearings and the thrust surface was terrible. When confronted The owner gave me a tirade of abuse, saying that it did not matter.. possibly true, but why not start with the better one?? He also advised against hardening the crank, even though he had little Stag experience. Basically his stance was that he had 30 years of experience and I was an a$$^ole. Needeless to say I will not use or recommend that shop again.

Pics below show the crank as received.

Aug 2017:
So I started again.. I found another machine shop and they advised that the mains could not be fixed without major work as it was not just a matter of line honing them. As the crank was balanced for the engine I stayed with it and they fixed the thrust surfaces and repolished and then it was sent off to Shaftech in Ohio (http:\\ who did a fantastic job hardening and repolishing the crank again, it looks fantastic now no sign of pits and I would highly recommend them for all your hardening needs, turnround was great and I thought the cost was reasonable.. The other block was checked out and rebored to +20, The first was +40 so I also needed to buy another set of pistons but I was not going right out to +40 regardless. This caused quite a bit of extra cost but I am now ready to assemble this engine.

Now the crank looks like this. Clean as a whistle!

Aug 2017:
First job was to clean and paint the engine, I used POR engine paint which seems pretty tough, Then soapy water and a hose to clean out anything left in the block. It was pretty clean and had been shotblasted and cooked. The oil plugs looked fine but I stressed about them so removed the one near the distributer to find that it was in fact fine, apparently they rarely fail. Inserted the core plugs and as I plan to use an electric water pump (A Craig Davis pump was secured as a Christmas pressy!) I used core plugs to seal off the old Water pump. A 1-41/64ths and a 1-45/64ths seem to fit nicely. The new +20 pistons were only 10g lighter than the +40 so I'm not getting into rebalancing the crank, its within normal tolerences apparently. I spent a long time identifyng some IWIS chains that fit and are available in the USA, and got them for under $75. they are the G68V-2 type and these are apparently the best IWIS make. Also Found that my donor engine had German SWAG camshaft gears so will reuse them as well.