Project TR7 part 12: The devil is in the details

The transmission is off the back of the engine.

By now, you’ve likely picked up on one of my many personality flaws. One of the biggest: I can’t stand sloppy car repairs. So I spent the better part of a broiling Sunday afternoon fixing a few things on Project: TR7 that would annoy me if I let them be.

The thick layer of grimy, petrified oil on Project: TR7, on the engine, on the subframe, and on the frame rails, tells me the car had some incontinence issues. First order of business: Remove the transmission and flywheel. Working by myself under the car, that exercise took about 90 minutes, despite the tight quarters.

While the flywheel was at the machine shop being resurfaced, I examined the rear main seal and found the area clean and dry as a bone. The old seal was still fairly supple after four decades, but I replaced it anyway. With the car that far apart, it is silly not to replace an $8 part that could come back and haunt me a few miles down the road.

The other places oil could leak from — the front engine seal, valve cover gasket, oil pan gasket, and the O-rings in the external oil pump and oil transfer housing — were given new parts. The inside of the transmission bellhousing was covered in thick, hard, greasy oil.

The transmission front seal was leaking, which coated the bellhousing with slimy oil.

Gunk, steel wool and elbow grease and a new seal should keep things clean and working properly.

With two cans of Gunk and steel wool, I cleaned the transmission. Then I replaced the front and rear seals, which were no longer pliant. Hopefully, the TR7 engine and transmission will now retain their bodily fluids.

The TR7 transmission gets a new rear seal.

Then I replaced the eight tired rubber bushings between the shifter housing and the transmission. A good two sweaty hours were consumed by YKC957 – that’s the bracket that holds the middle part of the exhaust system in place. Someone at a muffler shop cut the old one in half and used a generic rubber hanger.

A new exhaust bracket replaced the mangled old one.

That kind of thing annoys me. Because the emergency brake cable runs through YKC957, I replaced the two rubber grommets on the compensator lever and greased the whole works. Now, the e-brake works as good as new. And the exhaust system hangs exactly where it did when the car was new.

One of the tricks I use to find NOS parts is to simply type in the original factory part number into Google and on eBay. That’s how I found YKC957, a fairly obscure part that usually lasts the life of the car. There were two on eBay; I bought the least expensive one. Cost: $18. Over the winter, I snagged an NOS clutch and pressure plate on eBay for less than $100. Googling original factory part numbers can turn up all sorts of treasures, and I recommend this strategy for anyone who works on their old cars.

The flywheel looked pretty knackered … but a visit to a machine shop and $25 changed that.

Resurfaceing the flywheel is essential when replacing the clutch.

A new old stock clutch replaces the 40-year old original.

With the resurfaced flywheel and new clutch installed, it was time to deal with the refreshed gearbox. I slid the transmission under the car and then I lifted it onto my floor jack. The plan was to get the transmission in position and then summon Autoweek digital editor Andrew Stoy to help me mate it to the engine.

I know from experience, it’s far easier to remove a transmission than it is to install one. But, just for the heck of it, I jacked up the transmission until it was level with the back of the engine. Then I lined up the transmission input shaft to the clutch disc and rolled the gearbox forward. It took a little wiggling and jiggling but the gearbox slid right into place. I raised the rear of the transmission and bolted the crossmember to the frame and then I installed the bellhousing bolts. The whole job took about 90 minutes. This is one reason why I really like working on the TR7. Most jobs you can do by yourself.

From there, it was off to the races. In the span of a few nights in the garage after work, the driveshaft, starter, alternator and shift lever, and the shifter console inside the car, were reinstalled with little or no hassle.

Though I bought a new water pump, I wasn’t planning on using it since the old one wasn’t leaking. But Autoweek reader Mike Smith, himself a TR7 owner, changed my mind with a comment he left a few weeks back: “I have said this before, but before you close everything up, do yourself a favour and replace the water pump. The one on my TR7 took less than an hour… It will be worth the minor hassle, and then refill with good quality multi coolant to lubricate and manage the mixed metallic materials in the engine.”

The old water pump had to be pried out with a balljoint fork.

The old pump, which is gear-driven off a jack shaft, is another Triumph weirdness. But this time, it’s Saab’s fault. The first versions of Triumph’s slant four engine powered late ’60s and early ’70s versions of the Saab 99. Because Saab agreed to buy 50,000 slant-four engines a year from Triumph, the Swedish company was able to dictate one design change that greatly complicated and seriously weakened the engine: the location of the water pump moved from its traditional place in front of the engine to top of the block with the impeller facing up.

The water pump sits on top of the block, a design that caused massive problems

That’s because in the 99, Saab installed the engine backwards, with the flywheel facing forward and the nose of the engine inches away from the firewall. With the water pump in the normal position, it would be an engine-out job to replace it. And that’s how the water pump changed locations from chief engineer Lewis Dawtrey’s original 1963 design. The impeller sits about level with the top radiator hose. If the coolant level drops below that, overheating, a blown head gasket and a warped head soon follow. Project: TR7, a later production model, came with a low-coolant warning sensor designed to help prevent maladies.

After the water pump came the exhaust system. On a Triumph club forum early this spring, I found for sale a new old stock set of Pacesetter brand headers from the 1980s in a never-opened box.

These NOS Pacesetter headers should yield about a 10 percent increase in power.

The headers are a perfect fit.

Cost: $200. Those fit beautifully and should work well with the high compression pistons and mild cam. The exhaust note will hopefully be a bit raspy, but quiet.

The rest of the exhaust system is stock and will hopefully be quiet.

That last thing I want is for a flatulent sounding Project: TR7 to attract the unwanted attention of drivers of modified Subarus, Hondas and cars of that ilk. Despite my efforts to boost the TR’s performance, the car is very likely not going to keep pace with most modern machinery.

The cost for this part of the mechanical renovations total $694 and break down like this:

The TR7 engine is coming together and looking good.

All that’s left to do now is rebuild the SU carburetors and make two key modifications aimed at sending more of the engine’s power to the wheels. The mechanical engine cooling fan is being replaced with an electric one. And the mechanical fuel pump will give way to an electric pump. Finally, I can say we’re getting close to the finish line.

TR7 cooling will be electric now.

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