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Project Lucas, A Drastic Change In Direction

Well, since my last update, it’s all gone downhill.

I left the last update on a high. The car was running well, the engine was quiet, and Lucas had just flown through a WOF check.

To celebrate this success, I decided it was time to deal with the thermostat. Lucas was running cold on the gauge (about 1/4, where it should be just under half), so this was the logical starting point. I also had a bunch of new hoses to fit as everything was a tad neglected and perished.

I started by making a mess by removing the top hose from the radiator and draining as much coolant as I could.

Followed by removing the hose completely, which revealed this mess

I knew this hose had been weeping from both ends at various times, but this build-up was just gross.

The other reason I wanted to do the thermostat is that it is easier to replace the hose that resides under the housing, which goes to the back of the waterpump. This had an intermittent leak and no amount of clamp tightening was stopping it.

I gently removed the two bolts holding on the thermostat housing, which when removed unleashed another torrent of coolant, this time going straight down the valley gasket and appearing down the back of the engine where it proceeded to pour onto the ground, with some hitting the drip tray that lives under the cars.

The housing was horrific once removed, so much gunk everywhere. The gasket had also been supplemented with too much of what looked like bathroom sealant.

There was a thermostat fitted, which was a good start. It was the wrong one, unsurprisingly. It was some sort of American one, and once the freedom units on the back were translated to normal units, it was about 82c, not the 88c the EFI cars should run.

I don’t know if it was stuck open or not, I wasn’t too bothered by that as I had a correct 88c thermostat ready to go in. The replacement also had a jiggle valve, which the old one didn’t.

With the housing removed, I had access to the hose under it. This wasn’t as bad as I expected, but it was swollen and the ends were cracking. The clamp on the manifold side was very rusty, which seems to be a common theme for these.

The replacement hose, ERC2278, was slightly longer and needed a bit of a trim to fit nicely.

The stub it goes on in the manifold needed a clean up too as this was quite crusty

Speaking of cleaning, I chucked the housing in the vice and attacked it with a spinny brush of death on the drill.

It came up pretty well, especially the mating surface

This meant that after running the bolts through a die and a tap into the mounting holes to clean the threads up, I could install the new hose and reinstall the housing with the new thermostat and gasket.

New thermostat installed. As my past experience has taught me, use a thin smear of sealant on both sides of the gasket, and make sure the thermostat is seated correctly and doesn’t slip down to get caught between the housing and gasket…

You can just make out the new hose under it, with new stainless clamps

A new top radiator hose was then fitted, with a thin smear of Hylomar on each end, just to seal any pitting in the surfaces.

Speaking of hoses, while in the area I wanted to replace a couple of hoses that I knew looked horribly perished. They were the two Extra Air Valve hoses. You can see these in the above photo, to the left of the thermostat housing.

The first hose, right above the thermostat, was missing a clamp and was badly perished. It looks like it hasn’t had a clamp for a looong time.

This wasn’t too hard to replace. I did have to undo one bolt that secured the air rail under the throttlebody, so I could move the air rail away from the EAV and get more space to slip the hose in. Other than that, a lot of silicone spray and on it went.

The other hose, that C shaped one on the left, was a bit more of a pain. It came off easy enough, but you can see how much it had swollen

This meant the new hose was a very tight fit over the fittings. In the end I soaked the hose in hot tap water for a few minutes and then used silicone spray on the fittings to squeeze it into place.

It’s a big improvement though

With those hoses installed, I filled the cooling system and bled it. The trick I found, in my vast experience of replacing coolant in these things, is to remove the two screws holding the expansion tank and place it on top of the battery. This raises the high point of the system and bleeds air into the expansion tank. You can really notice the difference the moment you lift the bottle up, air immediately starts to bubble into it.

You can just make out in this photo that the hose from the tank to the radiator is above the radiator now, usually it’s below the radiator outlet

This bled the system very well, with lots of air coming through, and the thermostat opening nicely. It didn’t seem to make much difference to the temp level on the gauge, so who knows. I tested the gauge and when it’s grounded out it goes to the full range, so maybe the sensor is wrong. As long as the temp is stable, and it’s not leaking, I’m happy enough.

As one final job for the evening, I wanted to replace the distributor rotor and see if it improved the higher RPM stutter.

I removed the very original looking Lucas cap, to find a very original Lucas rotor arm

Now, this is where it went wrong. Much like the RV8 trick of not draining the oil with the filter removed, there is a trick with these rotors too… if they are stuck, don’t pull them.

What happens if you do, is that you end up lifting the upper section of the distributor out of the mechanical advance weights, which buggers the whole thing. The advance won’t work, and the rotor now sits too high. Basically, I had immobilised the car.

It’s not the end of the world though, the car came with a spare distributor… (oh no)

I made note of the rotor position, and removed the distributor.

Here the removed one sits above the “replacement”

Because the wiring has been messed with (the distributor should have an ignition amp on the side of it, but someone has rewired it to work with an HEI unit mounted on the strut tower. More on that later) I had to swap the altered wiring to the replacement distributor. I didn’t realise at the time that you can swap the wiring complete with the pickup between the two distributors (even if one was designed for the external amp and the other wasn’t), so I cut the wiring and soldered the connector on.

I then fit the new rotor to the replacement distributor and fit it to the car. I got it running, timed it up with the timing light, and it ran like trash. Odd.

In hindsight, I should have paid more attention to what I was putting in the car. I later discovered the replacement distributor was trash. It was broken, everything was loose, and I don’t even know why it was included with the car.

So, what now? Well at least I could move the car again, so that night I kicked it out of the garage again, to think about what it had done.

Needless to say, at this point, I was beyond fed up with the car. Going from the high of the car running, driving, coming to temp nicely, the heater working, no leaks, and then being slammed to the ground face first by the car suddenly being broken again… it’s not easy.

Oh yeah, it wouldn’t be me working on an SD1 without the floor looking like this. You can see the outline of the tray… it tried.

The next day, I set about stripping and repairing the original distributor.

This was the problem. The main shaft was sitting too high. The trigger gear/reluctor ring in the middle should be sitting down, with no gap under it. I have already removed the pickup in these photos; this would attach to the two threaded posts.

The rotor was cracked, even before I started

I had nothing to lose then. The general advice is to smash it off, instead of trying to pull or pry it off. Out came the hammer and chisel.

It’s off! And this is why you always grease the inside of the rotor before fitting. It was rusted solid.

Next is to remove, or break, the little plastic retainer (if it isn’t already broken). This lives down the center of the shaft, and is meant to hold the two sections together. Mine fell out.

Next, remove the circlip retaining the reluctor ring. Under this is a washer, and then a very flat and very hard o-ring. I had to cut the o-ring off to remove the reluctor ring.

Now gently lever the reluctor ring off, followed by removing the three standoffs that retain the advance plate below it

Now you can lift the whole advance mech free. You will need to unhook this from the vacuum advance lever. This lever just slots over a pin on the bottom of the advance plate. This will leave you with the bare shaft and mechanical advance.

Now the fun part, removing the shaft from the body. Use a punch to hammer the roll pin out of this hole

The drive gear will slide off now. I marked the shaft and gear so they installed the same way around. I don’t know if this was necessary, but I did it anyway.

Now the whole shaft should slide out the top of the housing

The advance doesn’t look happy. The springs should be flat.

Do note that the two springs are different and must remain in the same positions. One is thicker than the other.

So what happened? Well, when I pulled hard on the rotor, if lifted the top half of the shaft up. If you’re lucky, it might slip back down and be happy. If not, it could do a couple of things that mine did. First, there is a black plastic piece under the fixed plate on the bottom of the top shaft.

This plastic piece (orange arrow) is meant to fit perfectly on and lock into the metal plate (green arrow). Mine was out of place and stuck under the plate, stopping it from sliding down into place.

The other issue is more simple, the advance weights get caught under the lower plate.

Neither is really recoverable without stripping the distributor to some degree.

What I also didn’t realise initially, is that the top half of the shaft should move pretty freely. Mine was seized solid. This more or less means the mechanical advance hasn’t been working, as the shaft needs to be free to rotate for that to operate.

I unhooked the springs with some levering, and after much wiggling and some prying, the top shaft started to move. There was a buildup of old grease and dirt under it.

I removed and cleaned everything up, making sure the two shafts slid together and moved freely. I retrieved the plastic piece, which was thankfully undamaged, and fit it onto the upper shaft. Here you can see how it should fit together. I guess the plastic piece is a kind of bushing.

I gave everything a light coating of grease

And reassembled the two halves

Now it was just a case of refitting everything back into the housing, step by step, not forgetting the roll pin on the drive gear,

Once everything was back together, I installed the pickup, and using a thin slip of plastic from some packaging, created the required air gap between the pickup and the reluctor wheel. The pickup is magnetic, so you need a non-ferrous feeler gauge.

In the end, it took three distributors to make one good one. I had to steal some bits from another spare distributor I have (which has a locked mechanical advance for use with an aftermarket ECU), as the “spare” that came with the car was in such bad condition I couldn’t even scavenge that for much.

I fit the rebuilt distributor to the car, with a new cap and rotor, and timed it up to the 8 degrees BTC, and the car was running nicely, idling smooth and sounding good. The throttle was nice and responsive, and the timing light showed that both vac and mechanical advance appeared to be operating.

The old cap, was a bit old.

The final thing to change was the coil. I had done some reading about the HEI ignition amp that has been fitted to this car, and realised it’s designed to work with a low impedance type coil, despite not having a ballast resistor fitted. I still had the old GT40R that came with the car, So I refitted that.

I also finally figured out something that had been bugging me. There was a wire jammed into a relay holder under the dash, running through a hole in the firewall, to the coil. It turns out this was a bodged switched 12v feed for the coil…

This wasn’t my sort of bodge, so I set about fixing it. I knew from when I got the car that there was a standard, unused, connector right next to the coil; I don’t know what it was meant for, but it has a switched 12v feed in it. When I got the car the aux cooling fan on the trans cooler was powered by this (and running all the time the key was on).

I pulled the wire out of the relay holder, pulled it through the firewall and cut it shorter. I then crimped on a bullet terminal, and popped it into the relevant socket on the plug.

Works a treat, and now isn’t running into the car through a relay holder. Nice.

I also removed the HEI unit to check that there was thermal paste under it, as they run hot and need cooling. No, there wasn’t, just dirt.

I wire-brushed the paint back to bare metal and used some thermal paste before reassembling it.

The engine was now running great, so all that was left to do was to take it for a decent run and get some heat into it.

Before leaving the garage, I popped this spare standard chrome grille trim on

And then it was time to enjoy the sun, and take the car for a run.

It was a leisurely run, I was out for a cruise, not a race, but I did test the higher RPM performance once or twice, and it was silky smooth to redline now. Obviously something I had done fixed the stuttering. The engine was running awsome, everything was doing what it should, and the exhaust sounded great. Arm out the window, enjoying life.

I got about half way around my usual test course, about 5km into a 10km trip, and I noticed it.


Tick. Tick.

Just once or twice, mostly at lower RPM when slowing down.



By the time I got to the photo spot, the engine was clattering away like a champ. The “fix” lasted almost exactly 100km.

Clack Clack Clack Clack.

Oh well, I was there anyway, so I took some photos.

The drive home was one of shame. Trying to pretend like the noise was coming from the car next to you, not the old British clunker you’re in. Everyone looks, but not for the right reasons.

I was gutted.

I am gutted.

I got the car home, and sure enough, the noise is deep in the middle of the Vee, so it can only be something related to the cam or lifters. It’s worse when hot, but can be heard intermittently when cold.

Clack. Clack.

Unfortunately, that is it, that is the straw that has broken this camel’s back.

Not only do I not have the time, money or space to replace or rebuild the engine, I’m just over it. It’s been hard. This car kills motivation. For every success I have had, it’s been almost immediately followed by yet another failure.

I replace the power steering pump, and the replacement is broken. I replace that, and the coil dies. I fix the coolant issues, but the distributor dies. The replacement distributor is rubbish, so I fix that. I finally get it running well, try to enjoy a drive, and the engine starts clacking again. It’s a soul crushing loop.

What it needs is someone with the space to just rip the engine out, and fit a different one, going through all the other systems at the same time and just sorting it all once and for all. Doing it bit by bit clearly hasn’t been working for this car.

So, with that, the car is for sale. I hope it goes to a good home, I really do. Lucas deserves it. It’s not his fault that previous owners have been neglectful.

I feel like it’s a bit of a failure. I haven’t had to sell a car because it’s gone over the line I have drawn in the sand. Sure, Lucas is a LOT better than when I got him, but he is still broken and I don’t like that.

Who knows what the future holds now. Watch this space.

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1 year ago

Oh no mate! These SD1s put us through the mill, don’t they? I’ve been rewarded this year with a whole host of fixes, with each subsequent fix revealing something else that now needs fixing. Each causes me a bit of despair and each pushes me out of my mechanical comfort zone – and this is supposed to be my daily, so I have to jump on it!

I hope you’re able dig deep to see it through but totally get it if you don’t. Love reading your blog regardless of which car you’re writing about.