Lachlan's 1972 Datsun 1200 Sedan

[Lachlan]

Today was a good day.

 

 

[Lachlan]

Today I made a start on the non-functioning brakes. I'm anticipating every important part (master / wheel cylinders, pads, shoes, misc) will need replacing.

 

From previous inspections, I knew the master cylinder had one empty reservoir and a lot of corrosion-like substance on the metal case. The unit is a PBR master cylinder that I've learned many Australian delivered/built 1200s came with, not the more common Tokico / Nabco units that most USA and Japanese models came with.

 

Unfortunately, this means that if I can't get this one to play nice I've got a potential parts sourcing headache.

 

Dual Reservoir (rubber lid removed, both drained)

 

 

Master Cylinder

 

 

I concluded that the white corrosion-like substance was the evaporated brake fluid that had leaked out of the rear reservoir. Given my inexperience with brakes, I would read later that now would've been a great time to bleed the master cylinder. I've not done this before, thinking this would happen automatically when bleeding the whole system from the wheel cylinders.

 

After cleaning it up as best I could, I refitted the reservoirs and topped them up and moved onto the rear drums.

 

Left Rear Drum

 

 

The drum itself took me a long time to separate from the drum brake assembly. I think the rear drums are rubbing a lot as they were the only things holding it on.

 

Under the Drum

 

 

Looks pretty scungy and rusty. After taking heaps of photos, I was surprised that everything came apart fairly easily.

 

Close shot of Wheel Cylinder

 

 

It looked jammed up and rusty, and given it's an affordable off-the-shelf item, I'll be replacing these on both sides. It's another PBR item that I'm hoping will be much more straightforward to replace. Note more white substance towards the centre of the drum assembly.

 

Everything laid out in order

 

 

For someone who's always been mystified by the dark magic that is braking systems, this was quite enlightening for me.

 

Brake Line and Bleed Screw

 

 

I was ever hopeful that all I had to do was fill the master cylinder reservoir, bleed the brakes at each corner and voilà - instant brakes. No such luck. After seeing the shabby state of the wheel cylinder, I suspected they needed replacing. I put some homebrew penetrating oil on the brake line screw, gave it some percolating time, and ... rusted solid. The flare nut wrench wouldn't get it to budge, rather it was gently rounding the nut. This is a potential problem for future Lachlan.

 

At the end of the day, I tried doing a quick brake bleed to no avail. There's a slim chance that the master cylinder still works and I got air in it. Next time, I'll bleed it properly and have another shot.

[slowlearner]

I  guarantee your soft lines are junk anyway. 

[Lachlan]

It’s been a while.

I changed jobs.

 

I moved house.

 

I gained a garage. I am now fully armed and operational.

 

—

Because houses are so cheap here, I added lightness to my wallet and had the brakes done.

 

Refurbished:

- Master cylinder

- Brake booster

- Brake calipers

- Discs & drums

 

Replaced:

- Wheel cylinders
- Hard brake lines

- Soft brake lines

- Hardware

 

No outfit is complete without matching new shoes.

 

One safety inspection later and we got … rejected.

 

Reasons:

- Sway bar link bushings were toast

- Rust in multiple places 
 

Bushings are now done and rust repairs underway. All going well I’ll have plates this week.

 

That concludes this project, after which my plans are not set.

[Lachlan]

On 7/4/2023 at 3:36 PM, Lachlan said:

All going well I’ll have plates this week.

NARRATOR: Little did he know, he would not have plates that week.

 

Due to a stamping irregularity from the factory, confirming the identity of my 1200 has turned into a bureaucrat’s wet dream.

 

In NSW, the compliance plate (affixed to passenger’s side cowl) contains a 5 digit Serial number that must match one stamped on the body. Failure to locate a match means registration is denied AND gets reported on the car’s record due to suspicions of identity tampering.

 

During the inspections, this number could not be located in the usual locations. However, the inspector did locate two other numbers:

 

1. A body plate with a machine engraved body number (affixed to driver’s side hood ledge above wheel well) painted in the original body colour. This didn’t match ANY number on the car and had a format closer to Japan made models:

 

‘B110A XXXX’  — Australian models don’t contain the extra A.

 

First red flag.

 

2. Body number stamped on the passenger side strut top. This could be matched to the Manufacturer plate (affixed to driver’s side cowl) so it was a start, but did not satisfy. The inspector took issue with the way the numbers looked, implying someone had grabbed a hand tool and crudely whacked them in to make them match.
 

And I’m sure that’s exactly what happened 51 years ago in the factory by a line worker, well before either of us were born. 
 

Second red flag.

 

Mind you, not all was lost. The engine number matched the Manufacturer’s plate, the Serial number matched both the Manufacturer’s and Compliance plates and the body colour was clearly original and also matched the Manufacturer’s plate.

 

This being my first foray into classic cars, I was at odds to reconcile this situation. I was frantically searching for info online and kept coming up short. The inspector went inside for what felt like half an hour leaving me outside reassessing life choices and learning new words to describe the situation.

 

I wandered in and he was on the phone discussing everything with a representative from the governing body. An investigation was opened, photos were taken and I was sent on my merry way.

 

This was not good.

[Lachlan]

Adding to my stress was the fact the car kept dying every couple hundred metres on the way to and from the inspection station. If it wasn’t the middle of winter here, I’d have arrived in a pool of sweat from the nerves. Modern traffic is no place for a temperamental classic. Thankfully all quiet streets, but a few roundabouts for added challenge.

 

Given the last time it did this it was crud in the fuel tank blocking the outlet and lines, I’ve already pulled the tank for another thorough cleaning.

 

Returning to the story, I got a call late morning asking to come back down so the inspector could take better photos. Having only barely made it home I grabbed the work light and a DSLR and shot the highest quality photos I could. Sent and prayed.

 

Working from home has its advantages, one of which being regular viewings of the stable during ‘appreciation hour’ while waiting for the tea to brew. On one such viewing, I noticed we’d neglected to check the driver’s side strut top.

 

FOUND IT! The Serial number (one from the Compliance plate) had been stamped on the body in the same manner to the Body number on the passenger’s strut top.

 

Quick as lightning, I set the lights, grabbed the camera and clicked away.

 

Since sending them off, it’s been radio silence. Apparently I’ll hear back today but indications suggest the prognosis is not good.

 

In my slump, I searched far and wide for more examples of Australian assembled cars with similar markings to mine. And find one I did:

 

https://www.carsales.com.au/cars/details/1973-datsun-1200-deluxe-manual/SSE-AD-15192350/?Cr=1

 

Take a look at photo 27 of the engine bay from the driver’s side front wheel. That number stamped on the strut top is IDENTICAL to my car, just different actual digits.

 

It’s not over yet.

Edited July 11, 2023 by Lachlan

[KELMO]

Sounds like a complete pain in the backside to get registered for tags.

 

Good luck.

[datsunfreak]

8 hours ago, KELMO said:

Sounds like a complete pain in the backside to get registered for tags.

 

Yeas, I am thankful for our lazy motor vehicle departments...  😁

[Lachlan]

Shortly after posting the earlier updates, I got a call from the inspector.

 

It was good news.

 

Having pursued the normal path to no avail, he applied to register the vehicle with no compliance plate. This was the harder option but ultimately the right one.

 

He said there were extensive notes in the system that would be accessible when I went in to register, but it was all worked out and should be no problem.

 

I thanked him for his persistence and, as he wouldn't accept a gift in return, I left them a 5 star review on Google.

 

First hurdle cleared. Now to actually get plates and registration.

 

Plan was to get it sorted for the weekend so I could attend a local cars and coffee. So I took Friday afternoon off and headed in.

 

You know what's coming.

 

--

 

I brought all the required evidence, filled in the paperwork, grabbed a ticket and took my seat.

 

Finally my number was called and up I went.

 

We were off to a great start chatting about old cars and it looked like we were sailing through the process. The chap even got out some plates for me.

 

Then we hit a snag.

 

Up came those notes the inspector mentioned. I could see the focus intensifying and bodily movements slowing as he leant in to concentrate.

 

He called over another staff member for an opinion.

 

Then another.

 

Then finally the manager.

 

The notes were thorough and complete, however, none of them had ever dealt with anything like this before. Not what you want to hear.

 

They made some calls and given it was Friday afternoon, the people they needed had gone home for the day. So they took copies of all my paperwork along with the notes in the system and sent them through to another team for review.

 

No plates today.

 

--

 

Shortly after they closed, I got a call from the manager.

 

Registration has been approved.

 

Finally! So I headed back first thing Saturday morning, had yet another wide eyed look from the hapless service desk employee and eventually received my plates.

 

That was by far the hardest registration process I've ever experienced and this is my third time through the ringer for unregistered vehicles.

 

[Lachlan]

I've heard many people say the more you drive a classic, the better it drives.

 

I'm testing that theory by looking for excuses to take it out. I've already uncovered a few things that will need attention.

 

First proper drive was for fish and chips at sunset by the lake.

 

 

Golden hour.

 

 

Next came a slightly longer drive to church.

 

 

This lady (face blurred just in case) faciliated my purchase of the Datsun. She was surprised and thrilled to see it on the road again.

 

She keeps in regular contact with the original owners and mentioned they often asked about it. I remember them saying they were excited to see someone take it on so the car could live on. It definitely motivated me not to quit until I was done.

 

She and I had a photo in front to show them. I asked her if they all thought I would actually get it done.

 

"Nup". We both laughed at that.

 

To be honest, there were times where I didn't think I'd get it done. It feels good to back myself and come through with the goods.

[Lachlan]

Since returning her to service a few issues have emerged.
 

The temperature gauge didn’t work so I did some homework. A fault can originate from two areas:

• The gauge itself, and
• The thermal resistor (aka thermister) in the engine.

Before doing anything, I cleaned the metal connections to ensure good contact between parts. To test the gauge, I bridged the connector on the thermister to the negative battery terminal and turned the key to On. The needle moved off C and slowly up through the range. That clearly wasn’t the problem. Must be a faulty thermister.

 

I ordered a replacement and planned to install it on the weekend but never got the chance. The supplier contacted me saying they were out of stock. A problem for another day then.

 

When pulling in and out of the garage to wash it, I’d noticed the idle was a bit low and it conked out a couple times. This was new but I’d assumed just teething issues after sitting for many years. A couple days later I’d started tuning the idle speed and mixture and discovered three things:

• There is no fast idle adjustment on this carb. The screw I thought was the fast idle was just the regular idle speed. As I’d turned it a few times, when it came off choke (manual) the revs started racing up due to my incorrect adjustment.
• The there was now a smoke show out the back of the car.
• I couldn’t get it to shift into reverse or move under its own power.

The one positive was the temperature gauge now works so I won’t be needing that part, but the car doesn’t move anymore. Timing couldn’t be better as I’m anticipating an inspection from an interested party on the weekend. It’s just Doris chucking a tantrum so she doesn’t sell and stays by default.

 

Good times. More to follow.

Edited July 21, 2023 by Lachlan

[Lachlan]

After yet more reading, all signs point to an issue with the vacuum circuit to the transmission. Many posts on this site and others suggest two areas of possible failure and one other to check:

• The rubber vacuum hoses on either end of the hard line running from the intake manifold down to the transmission.
• The vacuum modulator itself which is screwed into the side of the transmission. My best guess is mine has failed in the open position and the engine is generating a constant vacuum which is pulling transmission fluid up the line and into the intake manifold. Cue smoke show for the whole street!
• The transmission fluid level itself can be the issue that causes poor shifting.

A few weeks prior to this, I had the car out of the garage and was trying to put it back in but couldn’t accelerate up the hill. After a couple attempts I made it up and suspected the transmission fluid had leaked enough to cause the slipping. Quite luckily I’d stored the drip tray under Doris thinking it was the only clear spot and soon noticed it covered in red transmission liquid. The leak was from the speedometer connector. Which doesn’t work either.

 

With the car running I topped up the fluid. I’d later learn the importance of bringing the car up to operating temperature before refilling the transmission fluid as I think it’s overfilled, but now I know. I’ll be dropping the pan, replacing the filter, fluid and gasket tonight so that will solve that problem.

 

I’ll take a closer took at the speedometer cable and pinion gear while I’m under there too as having a working speedo is somewhat helpful.

 

I’m really hoping that between replacing the rubber vacuum lines, filter and fluid on the transmission it will stop the smoke show and no shift / no drive condition. Otherwise it’s off to the city to grab a new vacuum modulator and fit it on the weekend.

 

Old cars, huh.

[RyanC]

Hey mate roughly where on the coast are you what lake is in the photos Macquarie?  Not many others on Ratsun that local to me.  

 

With another vehicle years ago we had issue with shifting and found low fluid the culprit, adding fluid is one thing finding the leak is the other 🤪

[Lachlan]

Hey @RyanC, just north of the Central Coast. Photos taken at Shingle Splitters Point on Lake Macquarie. Beaut spot at sunset if you haven’t been.

 

Yeah the only other guy I know is @slowlearner who got me onto here.

 

Still got the truck in your profile pic?

 

Thanks for the tip. I’ll see what effect the full service has but I think given the symptoms so far (particularly the constant smoke) there’s definitely a vacuum issue.

[RyanC]

🤣@Lachlan I grew up less than 5 mins from Shingles, Folks are still there.

 

Yep worked on the ute last night. Almost ready for rego, Im out near Kurri Kurri these days.

[Lachlan]

Very cool. You know it really well then! I spent time on Lake Munmorah growing up so Lake Macquarie is still new to me. Plenty of spots to discover.
 

Haven’t spent much time in Kurri Kurri but I have been to the drive-in nearby!

 

All the best with rego. Are you going standard full registration or classic/conditional?

[RyanC]

Yes the drive in is still running....just.  We were there last week.

 

Normal rego, don't want to be limited to when I can drive as will use it as much as possible,, is the plan anyway for now.

[Lachlan]

Parts cannon deployed!

 

Ordered a replacement vacuum modulator for the auto and PCV valve for the emissions system. Both came this week. Story behind the PCV is while I was under the car assessing the transmission, I noticed heavy dirt deposits all over the case and bell housing. When scraped it came off in dirty greasy chunks. Was caused by a long term oil leak and driving on unsealed farm tracks for years. Traced it back up the crankcase breather hose to the PCV in the intake. Time to replace!

 

While installing the new PCV valve, I also removed the other end of breather hose from the crankcase breather tube and it tore apart. Shattered! I thought I might’ve been able to skip replacing this but at 51 years old the rubber has all but given up. Sourcing a replacement was tricky but I found one in NZ. Grabbed a replacement valve cover to air cleaner hose as that’s showing signs of perishing too.

 

Back under the car, I discovered while undoing the old vacuum modulator that you need to grab the outer edge with the multi grip pliers. The inner part where you plug the rubber line into can turn within the outer part meaning it won’t undo from the case. After I figured that out the install went smoothly.

 

Question for the experts: Is it an issue that the rubber vacuum line between the modulator and hard line is at a fairly acute angle e.g. 90 degrees? It matches the old one but the line folds over instead of bending normally given the closeness of the parts.

 

Moving to the other side of the trans, I had a closer look at the now disconnected speedometer cable. I gave the end a gentle tug and it came right out of the housing. Cable snapped! Man, this car just keeps on giving. Sourced a replacement from Thailand. Hopefully I’ll have a working speedo after that.

 

The adventure continues.

[datsunfreak]

On 7/28/2023 at 7:35 AM, Lachlan said:

Question for the experts: Is it an issue that the rubber vacuum line between the modulator and hard line is at a fairly acute angle e.g. 90 degrees? It matches the old one but the line folds over instead of bending normally given the closeness of the parts.

 

Assuming air can still move through it, it should. But you might want to test that and see. 

 

Could also try a coil wrapped around the hose in the problem area? Something like this "hose bender" spring...

 

[Lachlan]

On 8/3/2023 at 2:20 AM, datsunfreak said:

Could also try a coil wrapped around the hose in the problem area? Something like this "hose bender" spring...

Great suggestion, thanks! If I can’t get it to work well, this will be my next step.

Work update:

 

Vacuum modulator fitted.

Vacuum hoses fitted.

Speedometer cable fitted.

Transmission fluid refilled.

PCV valve fitted.

Breather hose fitted.

Air cleaner hose fitted.

Started it this afternoon. Quite a bit of smoke still that lessened slightly as the engine warmed up. I’m going with the theory there’s still some ATF in the vacuum hose and it’s working it’s way through the engine.

 

Shifted through the gears while stationary. Transmission engages quicker than before. I guess that means the vacuum modulator is doing it’s thing.

 

However, it would not move when put in reverse. Seems as though the rear brakes are locked on as neither wheel would turn when both were lifted off the ground and the transmission was in neutral.

 

It’s one thing after another at the moment. I was hoping for a quick spin!

[Lachlan]

Shifting to neutral and releasing the handbrake, I shook it like it owed me money until it succumbed to my determination and released in an act of self-preservation.

 

Driving it for only the third time on the road was revelatory. It fires right up, idles steadily, shifts crisply, delivers power smoothly and has gauges that actually work: fuel, temp, speed and odometer.

 

And just in time too. I was planning months ago to take it up the Blue Mountains for a conference this weekend. I’ll probably break down but at least I’ll have had a real road trip with it before finding it’s next owner.

 

Why am I selling it again?

[datsunfreak]

6 hours ago, Lachlan said:

Why am I selling it again?

 

Because you want something to regret later? 😋

[Lachlan]

Doris Datsun dominated the 400km/250mi round trip to the Blue Mountains. With nary a complaint she stretched her legs on the motorways and enjoyed the romp through the changing scenery and elevation.

 

Discoveries along the way:

 

- A full boot/trunk of tools improves reliability.

- A mostly working temperature gauge is a revelation.

- Everyone hits their head getting in, even if you warn them.

- Auto shift points are set way too low which robs the car of power.

- Lots of wind noise is coming from the top of the windscreen.

- A proper wheel alignment would go a long way to improving handling.

- Non-original seats from a later model Datsun have gotta go.

Following day I caught up with a friend for coffee by the Hawkesbury River and it didn’t miss a beat. Gave it some curry on the Old Pacific Highway and it did surprisingly well. That is, until I was stuck behind a Volvo XC40 lumbering along well below the pace.

 

This week I’ll finish the colour and clear coats over the primer sections along with fine tuning the carb.

 

Question: How do you lift the cold start revs when there’s no fast idle adjustment on the carb?

 

I have a manual choke Hitachi DCG-306 with only curb idle and fuel mix adjustments. The owner’s manual suggests full choke with a single to-the-floor push & release of the accelerator before starting. It starts fine but quickly starts to chug unless you push in the choke a bit and compensate with additional accelerator input.

 

Note: The fuel float is letting slightly too much fuel in the bowl because the fuel level is more than 1mm above the centre of the window, so that might be a factor.

 

Photos to come.

[datsunfreak]

7 hours ago, Lachlan said:

Question: How do you lift the cold start revs when there’s no fast idle adjustment on the carb?

 

I assume you want another answer besides...

 

7 hours ago, Lachlan said:

full choke with a single to-the-floor push & release of the accelerator before starting. It starts fine but quickly starts to chug unless you push in the choke a bit and compensate with additional accelerator input.

 

...which is the correct/only answer. 👍

 

 

Sounds like someone is experiencing their first old car with a manual choke and super basic carbie.  😁

[datzenmike]

 

 

The fast isle cam may be stuck. Liberally spray the back of the carburetor with WD-40 or equivalent. It's the plastic thing above, though early ones may be metal. When the choke is applied the cam turns and blocks the throttle closing forcing a fast idle. When choke is released the cam lifts out of the way and the throttle can close. It has steps on it for different degrees of choke.

 

Spray, and while holding throttle slightly open, work the choke on and off. Work all linkages till they move freely by their own weight.