1970 Triumph TR6 Restoration

Proper electrical grounding is essential for reliable operation of the car’s electronics.  Here’s how my TR6’s battery was grounded:

In case you can’t tell, it’s a length of red wire (typically used for positive), partially wrapped in black electrical tape, and terminated at a bolt on the transmission:

As with many of the tasks performed on this TR6, step 1 was “undo”.  As an aside - if you’re wondering what that blurry bit on my accelerator shaft is, don’t worry, I’ll come back to that later (remember what step 1 was?).

A proper ground for the TR6 involves the use of a braided cable that connects to the battery, engine, and body.  You can see the body connection bolt (with nothing on it) in the previous photo. I took the cable off the battery and the transmission, then replaced the transmission bolt since the new cable wouldn’t be connecting there.

The new cable would connect to a bolt on the rear engine hoist point, the previously mentioned body bolt, and the negative battery terminal.  Here’s the engine hoist point as I found it.  Can you see what was wrong?

Yep, looks like someone forgot a bolt.  At least it was still in the block.  I did not have one of the braided cables (nor did I wish to buy one), but I did have access to lots of big wire, so I grabbed a couple feet of 4 gauge stranded copper and made one:

I reused the end from the old cable, and fabricated a new clamp for the mid section that attached the bare portion to the body.  I ended up soldering this clamp to the bare section to ensure a perfect connection at all times.  I then sanded the area around the body connection down to bare metal, and cleaned the hoist point connection as well, then hooked it all up.

Remember that bit I mentioned earlier?  Well it appears as though someone replaced the worn out accelerator shaft bushing with a section of rubber line and a hose clamp.  Ingenious!  This is also a good shot of the new end and middle connectors.

Here’s the new battery end:

I included that shot to point out the shutoff knob.  I think I got this for a few bucks off ebay, and I highly recommend it.  Opening the switch will prevent the battery from dying due to any stray currents while the car is off.  As a bonus, any time you do electrical work you should disconnect the battery, and this makes it trivial.

In addition to this main grounding point, the TR6 wiring harness has a few other grounds.  There’s one in the rear (no photo, sorry), and this one in the front by the grill (which was fine on my car):

There is also one near the battery on the passenger side of the car in the form of a small tab welded to the body.  On my car this tab was broken off, but you could still see the base.  I tried to make it easier to spot in this photo (the nail points to it, and I highlighted it):

The plug that is supposed to go here still existed, but was rusty, and I think it had the rusted remains of the tab stuck in it:

I made a new tab out of a piece of a picture hanger, and after cleaning the area down to bare metal, tacked it on with the welder.  I also removed the old plug and soldered a fresh one onto the wires.  I prefer to solder and crimp because it gives a much more solid connection and doesn’t allow for corrosion to get between the crimps and the wires.  Here’s the new tab with the new plug connected.  That little piece casting a shadow is the remains of the old tab:

Once I am further along (or if I notice odd things happeneing electrically), I may need to add additional grounding wires, especially from the lights to the body, but I’ll cross that bridge when I come to it.

There’s one spot on the frame that has always bothered me, and it’s this slight bulge next to the outer passenger side trailing arm mounting bracket:

There’s a piece of reinforcing metal inside the frame where that trailing arm mount attaches.  It’s not uncommon for this to rust out on TR6 frames.  I decided it was time to see what was going on here before I put the floors back in and lost easy access to the area.

Directly under this spot on the frame was a noticeably thin section that crackled when I pressed on it hard.  I easily hammered a screw driver through it and pried it open to get a look inside.  There was plenty of loose rust and dirt, and the reinforcement metal was covered in surface rust, but it appeared to be solid:

I haven’t made up my mind yet on what I want to do with this bit, but it isn’t delaying anything.  I have plenty of jobs to keep me busy before the floors have to go back in.

Included in my “inherited” parts stash was a new exhaust (never used, but a tiny bit of rust).  It included nearly everything I would need to replace the exhaust from the manifold on back, but I didn’t realize I had anything other than the major bits until after I bought a $50 exhaust hanger kit.  Oh well, spare parts!

The old exhaust was still servicable, but very rusty.  It was just going to be in the way when painting the frame, and I had this new one to replace it, so off with it!

The exhaust on my car consists of a downpipe, a stright(ish) pipe, and a muffler/tailpipe.  The downpipe is supposed to attach to the manifold by three studs (mounted in the manifold), lockwashers, and brass nuts (lol).

Mine was held on by two rusty studs and nuts.  The other stud was broken off and none of them had washers or brass nuts.  On one the nut was so rusted that the stud twisted out when I tried to take it off.  It would have been awesome if they all did this, but the other one was firmly embedded in the manifold, and the missing one was broken off below the surface.

If you are replacing the exhaust on your car and the existing studs look usable, you may not want to replace them as it is a giant pain in the ass.  Then again, if they look usable they probably aren’t as rusted to the manifold as mine were.

I tried to use an extractor on the broken stud, but that ended up snapping off, as did the drill bit when I tried to start over.  I finally ended up drilling out as much of the old stud as possible then using an air chisel with a pointed bit to break the remainder loose and fish it out.  I ended up with a only a ¼ moon like piece.  I didn’t have a tap and die set, so I somewhat rethreaded the hole by running a bolt of the same size in and out a few times.

Two down, one to go.  The last stud was intact, but horribly rusty.  I had been hitting it with PB blaster regularly for a week, tried heating it with a torch, tapping on it, and reasoning with it, all to no avail.  This thing was not budging.  Finally I just drilled it as close to the threads as I could then tried to twist it out.  Most of it came out:

Everything but the threads anyway!  More time with the air chisel and I had the rest out.  The threads on the hole were a bit messed up though.

After some fiddling I got the new studs in (after giving them a coating of anti-seize).  The best way to do this is to thread a couple steel nuts onto the end, lock them together by loosening the inner one while tightening the outer (forcing them into each other), and then using a wrench or socket on the outer nut to thread the other end of the stud into the manifold.  The studs have a non-threaded section between the short manifold side and the longer exhaust side.  I tightened them into the manifold all the way to this point, which brough the end just about flush with the other side of the manifold flange:

Here’s where I hit another snag.   I could fit the downpipe in just fine, but I could not get the gap between it and the manifold to close.  I’m surprised I didn’t strip one of the brass nuts trying.  After a couple days of no progress I finally got out the calipers and did some measuring.

The new pipe extends 0.475″ past the edge of its flange:

The manifold has a slightly larger diameter (to accommodate this pipe) that recesses 0.35″ into the manifold:

Simple physics dictates that two objects can not occupy the same space at the same time (quantum physics, however, does not agree).  That leaves me with a 0.125″ gap to fill between the flanges. The crusty old gasket I pulled off measured roughly 0.2″ thick.  I think it may actually have been two or more gaskets stacked on each other:

The new gasket that came in my kit is 0.05″ thick:

My old exhaust pipe extended a bit less at 0.4″, but even then the new gasket wouldn’t compress.  I measured the depth of the recess in a few places since it wasn’t uniform, then transferred these to the pipe extension, and cut off a thin ring.

I put the new gasket back in and re-secured it to the manifold.  While it looked better, I could still feel a jet of exhaust leaking out.  So I took it apart again, ground down the end a bit more with a dremel, and used the new gasket that I found in my big box of inherited parts.  It was in a yellow envelope and I think it came from TRF.  This gasket was easily twice as thick as the one I got from Moss:

his time when I bolted it back together the combination of shortened pipe and thicker gasket resulted in no noticeable leaks. There might be a little sneaking by, but nothing I could detect. It looks a lot better too:

I recommend that you fit the entire exhaust system before tightening the nuts and the clamps between the sections.  If you have to play with the manifold side a bit, it is a lot easier to move the pipe around while the other end of it is supported by the middle pipe.

Speaking of the middle pipe, it took me a long time to figure out where the hanger bolted.  I was so busy looking for a spot on the frame or the floor that I totally missed the obvious location on the transmission.  The hanger has a nut welded to it that replaces the one on the transmission.

I think my old exhaust must have just been hanging here without support, because I don’t remember pulling anything off from this area.  The exhaust passes through the “T-shirt” part of the frame, so it may have been resting on the lower portion of this.  The old exhaust was also welded where the mid pipe met the downpipe, which I elected not to do.

The muffler attaches at two points - one by where the pipe comes in, and the other where the tailpipe leaves.  I reversed the hanger-to-frame bolt in the front mount because it was easier to fit a nut in the space between it and the trunk than to finagle the bolt through there.

I also had to remove some other weird hanger that ended with a very wide metal hook (think of a taco bolted to the strap).  I have no idea how it could have attached to the old muffler, so I wonder if it was even used.  The hanger by the tailpipe is pretty straightforward.

Finally, here’s the mouse nest that was blown out of the muffler (which had spent some time stored in a barn) when I first tested the new pipes:

The mice are presently unaccounted for and may still be inside the muffler.

I mentioned a few things about oil in my Spin-on adapter post.  Here’s the rest of that little job.

After I drained the old oil from the car I also removed the sump so that I could install a new gasket.  Here’s the bottom end of the engine with the sump removed (sorry for the blurriness, this wasn’t an easy angle):

Upon examining the inside of the sump, I was pleased to find nothing but dirty oil and sludge.  There were no noticable metal shavings, and even better, no thrust washers or set screws (problems I have heard are not uncommon).

Here’s the sump removed and laregly wiped down:

After cleaning as much tar out of the bottom of the sump as possible, i left the inside of it alone.  It was just going to be filled with oil again, so there was no point in degreasing it entirely.  I decided that I might as well paint the outside while it was off the car though.  I took a cup brush to it to remove as much grease, dirt, rust, and old paint as possible, then washed it down with degreaser and let it dry.

I plugged up the drain hole and masked off the bottom to keep paint from getting inside the sump or in the area where the new gasket would sit.

Finally, I hit it with a couple coats of black engine paint rated for 500°F.  I wanted to use a primer, but the store didn’t sell high temp primer.  It still looks like I got good adhesion though.

I wiped down the underside of the engine, put on a new gasket, and bolted the sump back on to a torque of about 18 ft-lbs.

Those are fingerprints from installing it in that last shot, not smudged paint.  It looks great now and will make it much easier to tell if I’m leaking oil (none yet!).

I also cleaned up the valve cover and replaced its seal, cap, and mounting hardware (except the threaded rods).  I had an extra bit of fuel line that was painted red, so I stuck that on too.  Here’s the cleaner and more colorful engine:

I put 5 quarts of Valvoline VR1 20W50 racing oil in it, but after a short period of running the engine it looks like I’m still a bit low on the dipstick.  It’s not leaking, so I guess the aftermarket filter adds a bit of capacity.

More than anything else, this job has been the source of my slow progress.  Ideally I would have loved to pull everything off of the frame, sandblast it, fix it, coat it in POR15, then put it all back together.  In reality I have a 1 car garage and no storage space, so the car stays together for now.  I can always pull it apart and redo the frame properly if I move to a house with more work area.  That said, I wanted to at least clean and coat the part of the frame that would be impossible to get to once the floors are back in place

What a job that turned out to be.

It’s hard to motivate yourself to go work on the car when you know that the next few hours will be spent either in some akward position working from above or on the creeper under the car where everything you clean off ends up in your eyes, mouth, hair and all over your face and clothing, and at the end of the night it will look roughly the same as when you started.  It’s not hard to see why other projects (and video games) won out over TR6 work.  Finally I knuckled down and decided to get it over with.

I started off by removing the fuel and breather lines along with the exhaust system.  My exhaust was rusty, but not in terrible shape.  I had been given a brand new exhaust though, so I decided to pull the old one for better frame access and put the new one on when I was done.  I left the brake lines in because they were in good shape, not leaky, and I had enough to do without a brake bleed and refill.

Here’s the best “before” shot I could find (I take a ton of photos, but never seem to have the before shot I wish I did).

This is a shot I took to remember how all the lines were routed, and you can easily see the levels of grease and dirt I was dealing with.  I think I had even done some cleaning before I took this.

The driver’s side of the frame looked completely different from the passenger’s side.  The driver’s side was much more greasy and oily, and thus had more paint and less rusty metal.  There was also a ton of what appeared to be greasy sand packed to the side of the frame.  The passenger’s side was mostly dry and had lots of surface rust.  Overall it looked good though.

Fast forward through hours of scraping, washing, scrubbing, and misery.  The frame was as clean as it was going to get, so I gave it a final degreaser wash, rinsed it, prepped it, rinsed again, let it dry, then coated it with POR15.  When painting the frame from below, this stuff will get everywhere.  I still have some of it on my arms, though I was able to get most of it off my face (I do not recommend using POR15 thinner to do this, it burns). I painted from the “Tshirt” of the frame to where I had the front jack stands.  I could reach more of the frame under the engine, but this would still be accessible after the floors were in and was protected by a thick layer of leaked engine oil anyway.  In hindsight, I should have also done the rear of the frame at this point, but for some reason I didn’t.

Here’s the result:

You can also see that I cleaned up the transmission a bit.  It looks much better all shiny.

The next day I realized that the back would be much harder to do with the exhaust on, so I set about doing the same thing to it.  Here’s how it looked after some wire brushing:

Notice the angled support on each side?  The one on the left looked ok:

I’m not sure what that bracket with the two holes in it is for.  The exhaust doesn’t mount there.  My only guess is that the fuel line/breather may have clips that go there, but I didn’t have or need them.

The support on the right looked like someone had hit it with something.  The one side was all bent in and there was a rounded impression in the face of it.  It also had a huge mud dauber nest in it.

Bending it back out wasn’t too hard, but I had to get creative on fixing the indent.  I ended up using a large C clamp to squish the metal back to relative flatness.  I then cleaned up the edge as best as possible and (crapptastically) welded it in place.  Turns out I forgot to turn the shielding gas on.  No pictures of my awful weld, but the piece held so I’m going to try and forget about it.  Fresh paint hides all.

I’ll admit that I rushed the cleaning of this portion of the frame, and there are a few areas where I may have painted over some grease or dirt.  I’m not concerned because I knew I couldn’t paint everything anyway, and if it’s bad enough I can always hit it later when more frame is accessible (like if I remove the rear suspension for some reason).

Here’s the end result:

You can see how i only painted part way up those supports.  I’m also going to paint the underside of the trunk at some point, but i didn’t have enough POR15 left to do it now.  I did save a little bit to do the part of the rear frame blocked by the jack stands and for any missed spots.

I’d like to say that this is the best low-cost upgrade money can buy, but I’m withholding judgment until I get the car on the road and put some miles on it.  That said, so long as this thing doesn’t leak or give me problems, it will be worth every penny.

For those of you who have never experienced the joy of a TR6 oil change, let me show you what you are missing.

This is the original canister style filter housing and element:

I actually think they look pretty cool.  The problem lies in how this sucker is mounted.

This is where it attaches, to the SIDE of the block:

I’m guessing the engineer who came up with this design also owned a shop towel or kitty litter company, because there is no way to remove the filter without dumping oil over everything below it.  In addition to this, if you actually want to remove the housing from the engine compartment you need to unbolt the clutch thingy (the one with the red hose coming out of it in the picture) and swing it out of the way first.  I couldn’t find an easier way to get the damn thing out.

Here’s the new spin-on adapter (Moss Motor’s version anyway):

The spin-on adapter basically adds a 90° bend so that a more common oil filter can be installed vertically from below, the way all cars should have their filters installed in my opinion.  95% of the oil stays in the filter as you take it off (unless you tip it), and all you need to deal with are a few drips from where it was screwed on.

Here’s the adapter and filter installed:

Remember the clutch thingy I mentioned earlier?  If your car has one of those you won’t have to remove it to screw on and off the new filter, but it interferes enough so that you won’t be able to mount the adapter perfectly vertically.  It has to be angled slightly towards the front of the car.  Here’s a shot from below showing how close it is:

As with many things TR6, there is controversy as to what the best filters and oil to use are.  There is also some variation between spin-on adaptors made by different manufacturers.  I’ll probably change this Fram to something else the next time I do a change, but I doubt it will have any negative effect for now.

The general consensus seems to be that the following filters are good (again, see what fits your spin-on, they differ):
NAPA Gold 1516
WIX 51516
K&N HP2009

I haven’t refilled my engine yet as I still need to put the sump back on, but for oil, I’m using Valvoline VR-1 20W-50 (most recommended)

These are also suggested:
Redline 20W-50
Rotella-T 20W-50
Brad Penn 20W-50
Castrol GTX 20W-50 + Blue STP (for ZDDP aka zinc)

I think 10W-50 is recommended for winter driving.

As for quantity, I’ve been told 9.64 Pints for 1968 through 1972, and 10.8 pints for later years.

I’ll update with new pictures tonight.  I’ve been doing a lot of work the past couple weeks and have some parts coming in today (gaskets, oil filter, etc.) that should allow me to fire up the engine again.