My 1967 Volvo 1800S Maintenance Log: No Sleep ‘Til Göteborg

Picture of Volvo 1800S

Last month, I shared my newest lifetime regret, the purchase of a mediocre 1967 Volvo 1800S, and as is always the case, it was not ready to act as a proper mode of conveyance should. Therefore, I’ve spent more time working on it than driving it, although I have now managed to put a couple hundred miles on the odometer; in fact, I drove it about 70 miles yesterday (as I write this), most of those at 70-75 miles per hour. I keep maintenance logs for my entire fleet of 11 cars on separate Google Docs, and I will use the Volvo’s as a springboard for a discussion about what I’ve accomplished so far. The logs themselves will be in italics, while additional commentary will be in plain text. I have redacted names of cities and businesses for privacy’s sake, but other than that, the maintenance log is in my own style of shorthand, typically only intended for my own future reference. This is what it’s like to own a neglected Volvo.

1967 Volvo 1800S Maintenance Log

6/24/25: Car arrived from…

The car showed up running but covered in lawn clippings on my preferred shipper’s single-car enclosed trailer.

6/25/25: 8,XXX, New Nexen tires from Discount, new battery from Walmart (Group 25). Added plastic bushing to carb linkage to take up some slack. Working at valve adjustment (they’re just noisy). Working on speedometer. Tightened up bumpers. Loosened rear brakes a notch or two (they are sticking). Added brake fluid to clutch reservoir. Mom and N cleaned the interior. I washed it.

Photo of Lucas Bistable Relay

7/7/25: As of right now, I replaced the overdrive relay with a dimmer relay from a Beetle and now the overdrive works.

The 1800S needs its Laycock overdrive unit because it has a 4.56:1 axle ratio and tiny tires, meaning that at 75 miles per hour, the engine would be turning 4500 rpm without it. Considering the Volvo B18B has a recommended valve clearance of .020-.022, the noise generating capability of such a drive would be beyond the endurance of my patience. The overdrive unit is triggered using a momentary switch on the right side of the steering column, but this means that it must use a switching (or bistable) relay. The relay itself physically switches from one post to another and stays there when triggered by the switch. Unfortunately, like many wires and electrical components in the Volvo, mine was melted, and the part itself is a Lucas component that is discontinued. Used ones are expensive when you can find them, because they are also found in the headlight circuit of later Volvos and are therefore in demand. Since I’m trying to save money on this pretty but flawed little car, I found an alternative.

I also replaced a large section of the wire to the overdrive light on the dashboard. I also took the driveshaft over to…, as the u-joints you got from…were not right for the car. They replaced the front flange (at the overdrive unit) as it was wallowed out, and they replaced two of the three u-joints (that’s all they had in stock). They also installed the center bearing and bearing support. I tapped one of the transmission crossmember bolt holes and tightened it up, but it needs a new mount. I also got it some floor mats. 

The Beetle used a bistable relay to switch between low beams and high beams, and those are easier to find and still reproduced (they cost about $25). Although I haven’t found a good way to screw the relay to the car yet (it’s not exactly priority number one), I stared at a few diagrams, plugged the wires into the locations where they seemed to make sense, turned the ignition on, shifted to fourth gear (there’s a switch on the shifter to provide continuity to overdrive in that gear alone), and listened for the click of the overdrive solenoid. It happened – Hallelujah. Freeway cruising speed is now 3400 rpm.

Summer 2025: Swapped exterior door locks because I broke the key off in the driver’s door, lubed lock mechanism and window tracks/gears. Swapped to a Bosch 009 distributor but swapped back to the old one, which is apparently out of a ‘74 or ‘75 Volvo 142 (or something like that). The 009 is just worn out (I think). The carbs have been synched, the valves adjusted 5 or 6 times to .020. The oil and filter have been changed (a bottle of Rislone added).

I mentioned in my first installment that I broke the key off in the driver’s door. The lock itself is a part of the door handle, and there are three studs with nuts attaching it to the car. One of them is so hard to reach that you will invent words that would make a good man cringe when trying to remove or install it. Once removed, it’s time to stare at the mechanism. I had it apart and together several times before I got the hang of how it worked, and now I have working locks.

Side note: Some Swedish parts bags have a moose on them.

I installed a new clutch master cylinder and had to bend a new line.

In the back of my mind, I knew I would have to do this job sooner than later; you may have noticed that I had to add fluid to the clutch master on the day it arrived at my house. The unfortunate part is that I couldn’t remove the hard line without damaging it, and I tried my best. The long flare nut was just not going to spin on the line, and I tried heat, penetrant, heat, penetrant…it just wanted to break that day. Luckily, I had a spool of brake line in the garage, and although my line won’t win any concours awards because those tight bends are difficult to make without kinking the line (I mean, look at the engine compartment, who cares?), I was able to use the original nuts (installed before I made the double-flare, of course).

It has new tie rods and ball joints, and I removed the steering wheel and moved it a notch to the right (it was a bit off).

This was a little sad. The ball joints and tie rods were all tight, but the boots were worn and they were probably original. Volvo switched to sealed joints (no grease fittings) right around the time the car was built, and I had troubling thoughts of those joints quietly rusting inside all that dried grease. My dad’s ’99 Mustang broke one of its sealed tie rods in his driveway; it had simply rusted apart, and it wasn’t even close to 60 years old like my Volvo is. He was on the expressway the day before, and that incident has haunted me since then, so out it all came.

Checked alignment. Fixed driver’s seat straps and added a stadium seat under the cushion. New speedometer cable. New fuel tank sending unit. New heater hoses. New antifreeze. Swapped rear drums side to side and scuffed them up (and adjusted them). New door mirrors (they are Lucas reproductions from…).

Fortunately, Volvo was very kind to mechanics. I’ve never had such an easy time replacing front suspension components; they are attached with bolts and nuts rather than rivets and use nylock nuts rather than cotter pins (I’d rather have the pins, personally). Setting the toe-in is also extremely easy; it’s adjusted at the center link, and there is no separate adjustment at each wheel, which is why I had to remove the wheel to straighten it, something you’d never do on a typical American car (you adjust the wheel using the individual tie rods).

8/19/25: The intake portion of the intake/exhaust manifold was cracked, so you veed it out and used some JB Weld, you dog. New Remflex gasket, and you tripled up the head pipe gasket because you didn’t realize that you have some Remflex material lying around. 

There was a slight exhaust leak somewhere in the exhaust manifold area, so I decided to buy some excellent Remflex gaskets and do the whole job at once.

Unfortunately, the intake portion of the combination manifold was cracked. It’s near the heat crossover, but I did something I’m not always keen on doing: I veed out the crack using a Dremel tool and added JB Weld. Although I have stitched engine blocks before, JB Weld has its place; it’s been sealing a crack in one of my ’53 Buick’s intake manifold runners for 10 years or so.

Here’s the manifold, coated in graphite lubricant, and the carburetor heat shield painted with engine paint and ready to install.

I made a mistake here and made a gasket sandwich for the head pipe flange out of header gasket material. The Volvo was having none of it; it blew them out within two miles. Luckily, I had a flat sheet of Remflex material I had forgotten about…problem solved (although I did have to jack up the engine to remove the head pipe when the manifold was installed, a bit of a pain).

Here’s that beautiful, expensive, and totally-worth-it Remflex gasket. It’s made of graphite and is thick enough to seal up to 1/16″ gaps/pits/etc. It’s the only thing that’s reliably sealed my ’53 Buick’s long exhaust manifold (and yes, I tried the factory method of not using gaskets).

Here’s the (almost) final manifold installation. Now, I had to do something about the fuel line that broke at the rear carburetor.

New transmission mount. Stadium seat under passenger side cushion (and you bought some lawn chair straps for someday). New fuel line at rear carburetor.

Working on SU carburetors is a new experience for me, and while I like the challenge, I don’t like the comparative lack of parts availability and their expense. The line from the float bowl to the jet fell apart, and they are only available as an expensive unit (the jet is the tall brass thing; the metering needle enters it and provides the correct amount of fuel to the engine based on speed and load). Since I wanted to start the engine to make sure my exhaust leaks were repaired, I used a fuel-resistant O-ring, a piece of steel brake line, and some 1/4″ clear lawn mower fuel line as a temporary repair. Luckily, my new jets came in from eBay within a few days, because I wouldn’t trust my repair very far (although it didn’t leak during the few times I drove it). These are the new jets and fuel lines.

In case you were curious how the “choke” works on an SU: The choke cable activates an arm that physically pulls the jet off the needle, which supplies more fuel. Here is the jet in the fully choked position.

Here it is with the choke off, fully retracted (and a little blurry…sorry). By the way, the nut above the jet is how the idle fuel mix is adjusted; think of it as the idle needle on your standard carburetor (although that’s not a completely accurate comparison).

Here is a video of my exhaust check. So far, so good, but I had yet to blow out the gasket at the head pipe. (It’s not as clattery in person as it sounds on your phone, by the way, even though it’s far from quiet).

8/20/25: New transmission mount, but the transmission sure is leaky

8/28/25: Replaced red wire from fuse block in engine compartment to taillights and from taillight junction to license plate lamps, replaced passenger front parking light bulb and lubed socket, cleaned fuse block for lamps

It was around this time that I realized that the taillights decided to work intermittently. Some people shouldn’t be allowed to work on electrical equipment, because this was the harness that someone “designed” to operate the license plate lights. I have never seen so many scotch locks and burned wires on an old car in my life, but I’m working through the mess. I now have fully operational exterior lights, although it will need a new headlight switch ($$$) because the rheostat found the nearest exit and someone bypassed the dimmer with, you guessed it, scotch locks.

One thing that helps me on these electrical jobs is to buy a large, color-coded electrical schematic for my car from eBay. It’s laminated and just makes deciphering where everything runs that much easier than a black-and-white schematic from a faded or reproduced service manual.

If you were ever curious about what it’s like to make bad automotive decisions, I hope this piece has been instructive. What’s left to do? Well, the work on an old car is never done; it’s just that the jobs either become much more serious, or you get lucky and work your way through the minor quirks once the storm passes. In the case of the 1800, it has low(ish) oil pressure when warm (45 psi or so on the gauge at speed – it’s supposed to have 50-80). The carbs could stand to have the throttle shafts rebushed. The vent window and quarter window gaskets need replacing. I’d like a set of driver-quality chrome bumpers. And the list goes on…and on. Maybe next year, I’ll have the mental reserves for another update. But in the meantime, I have a Dynaflow to reseal in a ’53 Buick, a winter job if I ever saw one.

Epilogue: I couldn’t leave well enough alone. I used my borescope to inspect the cylinders, and although the engine has .020 over pistons (signifying a rebuild at one point), it’s clear that at one time the rings were rusted to the cylinder walls, especially on cylinder #2 (as evidenced by the lower cylinder pressure). All of these numbers are lower than Volvo specifies (170-200 psi), but that can be attributed to any number of things, such as a thicker head gasket than the factory installed. And pitted cylinder walls.

I also temporarily installed an auxiliary oil pressure gauge because I didn’t trust the Smiths unit, but it turns out that it was correct. Oil pressure specifications state that 50-85 psi at 2000 rpm is what you should be looking for; I have about 35 psi hot (at 2000 rpm). At startup, it’s 70 psi, and although it will climb to 45-50 psi at higher revs when it’s hot, it is clearly low. Therefore, I’m dealing with a worn engine, but I’m pretty good at nursing worn out engines for a long time; after all, I only drive these cars 500-1000 miles or so a year each. When I feel like there’s no putting it off any longer, I’ll hope I can find oversized pistons for a B18.

Photo Credit: Mrs. Aaron65

As I heard someone ask on Cold War Motors, a YouTube channel I watch, “Why are we wired this way?” Indeed, it’s past fighting.