Our Cars : Triumph TR7 update
I am sure that one day far in the future, when I look back at the more than 30 Triumph and Rover cars I’ve owned, worked on, restored and modified, there is going to be one that stands out as my all-time favourite. I think I know which one it will be.
Not long after I touched those first wrenches to my 1981 TR7 PI, I realised this would be a special and unique project. To recap, the silver TR7 was deposited in a storage facility in South East Michigan in the summer of 1985. There, it was surrounded by unopened boxes of old dolls and aeroplanes and covered in dust. Just 712 total original miles had ever passed under its wheels. The TR remained entombed and forgotten about until this summer when my $1250 cash liberated it from its elderly keeper.
I was hoping for a quick project to return the car to roadworthiness with as little work – and financial outlay – as possible. I figured the TR7 would need a thorough going through, but no major surgery. After all, with just 700 miles on the clock, what could have gone wrong? Plenty, as it turns out. What went wrong with the TR may be a window into Triumph’s final days in the U.S.
I felt a bit like a Forensic Scientist as the repair process got under way and I started removing the various parts. We know the TR7 OHC Slant four engine has its weak points but none were ever bad enough to call in prayer-mumbling priests for last rites after just 700 miles. There must have been other reasons why the TR failed and I was determined to find them. Turns out, the clues were there so now I think I know what went wrong.
In the first article about this car, I detailed finding it, getting it home and getting it running just well enough to limp into the garage for reparations. Now, five months later, the TR7 is once again roadworthy and trustworthy. I can now bring you up to date and close out this latest chapter of my Triumph adventures.
I left off here… Cylinders one and two tested at 160lb. Number three sported a worrying 130 pounds but number 4 showed only 30 pounds so the TR had either a blown head gasket or needed rings or valves.
Hours after I wrote those words, the TR started down that long road back to health. Removing the cylinder head from an OHC Triumph engine is almost always a worrisome affair because of the angled stud and bolt arrangement. Not this time, though – the studs and bolts were nowhere near the proper torque. They came right out and the head came off without fuss.
The TR7 had indeed blown its head gasket and that had filled cylinder #4 with coolant. The car had just been sitting like that for 25 years. During that time the pooled coolant and the rust it created left a 1/4 inch depressed area in the cylinder walls and collapsed the rings on the piston.
This discovery of major engine damage was a clue, one important enough to allow me to posit a reasonable theory on how a TR with 700 miles could fail so catastrophically. There were other odd things about the car that also might explain what caused it to die early.
You may recall that the boot of the TR contained several brand new, boxed BL items that the selling Dealer never installed. The boot held the original AM/FM radio, a stainless steel luggage rack and door edge guards. These items would have normally been installed BEFORE the car was delivered to its first owner.
The quick engine failure, accessories in the boot, and the car’s late sale date – the 28th May, 1982 – leads me to believe that my TR7 never received its PDI – Pre-Delivery Inspection. The PDI requires a dealership technician to, among other things:
– Top up all fluids
– Check the torque on all major nuts and bolts
– Install the accessories and customer-ordered options
– Test drive the car to verify that all systems are performing properly
– Sign the Passport to Service booklet to confirm that the car is ready to be delivered.
The car’s first owner saved every scrap of paper that came with the car and passed them to me. However, there is no record of any Dealer preparation and no Passport to Service. The original owner told me the dealership was going out of business and this was one of the last cars it ever sold.
At Solihull in January 1981, when my TR7 reached the end of the assembly line, it was likely given a shot of petrol, engine oil and coolant and then test driven a few miles to ensure it was ready to ship to the Dealer.
It seems very likely that, when my car was handed to the first owner 18 months later, it contained only the fluids put in at the end of the assembly line. Combine no PDI with infrequent use and a lack of any kind of maintenance and it is easy to see how things went so wrong. Indeed, I found no evidence that any maintenance had ever been performed on the TR. I removed the car original AC oil filter, air filter, Unipart spark plugs and Bosch fuel filter.
A receipt for petrol from June 1985 found in the cubby box may be the last time the car was on the road. By summer 1985, the TR was well out of its warranty period and the selling Dealer was long gone. When the head gasket failed, it would have been up to the owner to pay for the repair and that would have been an expensive one. Add a large repair bill to the $287 per month being to pay off the loan for TR7 and it is easy to see why the TR got deposited in that dusty storage facility.
Back in the here and now, I formulated a repair plan once the full extent of the engine damage was known. The engine came out and apart. I slipped away into the garage each night after dinner, making steady progress. The block and head came apart easily and were taken to a machine shop. $650 later, head and block were ready for reassembly. The block sported a new liner in bore #4. Luckily, the head was not warped. It was given a light skim and a valve job.
I did not buy the TR with the intention of keeping it but that started to change as I dug into it. With the engine apart, I decided to make a modification to improve performance. The USA low compression 7.5:1 pistons gave way to a proper set of UK high compression pistons. I wanted to see if these pistons would work well with the Bosch fuel injection. I installed new rings and Vandervell bearings, all new seals and sundry parts. I painted the block.
The radiator went out for cleaning. All the fuel and coolant hoses were replaced. A new water pump was installed. I replaced the fuel pump and filter, cleaned out the petrol tank and fitted a new clutch. Then I reinstalled the powertrain. Next came another modification.
The 1981 Federal TR7 came fitted with a large, heavy catalytic converter, located just underneath the starter. I replaced it with the standard UK market down pipe. This now feeds into a stainless steel centre silencer, which is connected to one half of a TR8 rear exhaust. The standard TR7 rear system has a big, round silencer that snuffs all the character out of the exhaust, making the TR7 sound more like a lazy Toyota than a real sports car. The TR8 exhaust sits in the same position as a TR7’s and has smaller rear silencer. It’s worked a treat and now the TR7 has a nice throaty bark.
Finally, in early November, I was ready to turn the key and, when I did, the TR7 fired right up and settled into a smooth, but noisy idle. Pressing the clutch pedal stopped the gearbox input shaft from spinning and silenced the grinding noise – another clue that makes me believe in my no PDI theory.
This is not commonly known, but BL vehicles with Rover’s LT77/R380 gearbox cannot be towed with the rear wheels on the ground unless the driveshaft is disconnected or the engine is running. That’s because there is an engine-driven oil pump in that ‘box that lubricates the bearings.
When the head gasket blew, someone likely towed the TR7 with the rear wheels on the ground and damaged the transmission. Indeed, the front chin spoiler reveals marks that could have been done by a sloppy recovery truck driver. Still, the gearbox is healthy enough to work, so I took the TR7 around the block a few times to verify that there were no leaks from the engine and that the air pockets were out of the cooling system. That done, it was time to get to work on the brakes and suspension. New shocks and attention to the brakes at all four corners in the form of rebuilt calipers and new wheel cylinders, took care of the major remaining repairs.
I came across a set of four factory alloy TR8 wheels at about this time and bought for just $57. I sent them out for restoration and had them fitted with new tyres, replacing the 30 year old Goodyear G800s and so, for the past week or so, I have been using the TR7 regularly. Mileage is up to around 900 now. She’s running, stopping and turning great. Eventually, the gearbox will have to come out but the TR7 is back stronger and better than ever.
All told, I have spent around $5000 on the car, including the purchase price. I probably couldn’t sell it for that much and yet I don’t care. I have had so much fun bringing it back to life.
Previously, I wondered what I should do with a TR with so few miles. There can’t be many left in the world with fewer than 1000 original miles. Now, though, it’s all become very clear… My TR7 will be used for the purpose its Designers intended: to be driven and enjoyed by people who appreciate fine design and good handling in a stylish, comfortable water-tight well made British roadster.
Read the first instalment dated the 29th August, 2010 HERE.
Is the Editor of the Parkers website and price guide, formerly editor of Classic Car Weekly, and launch editor/creator of Modern Clsssics magazine. Has contributed to various motoring titles including Octane, Practical Classics, Evo, Honest John, CAR magazine, Autocar, Pistonheads, Diesel Car, Practical Performance Car, Performance French Car, Car Mechanics, Jaguar World Monthly, MG Enthusiast, Modern MINI, Practical Classics, Fifth Gear Website, Radio 4, and the the Motoring Independent...
Likes 'conditionally challenged' motors and taking them on unfeasable adventures all across Europe.