Zel's Fleet Blog - BX, Jag XJ-S, Sinclair C5, Mercedes 208D & 230TE, AC Model 70.

[Zelandeth]

Correct Jim, it's a Weber - precisely which one I can't remember off the top of my head. Valve clearances are also on the list - once I've got a new set of rocker cover gaskets anyhow. The engine is currently actually oil tight, so I'm not tempting fate until I've got a new gasket set! I'll get a new set of head gaskets ordered in at the same time (Steyer-Haflinger still offer service support for the power unit would you believe), and probably both crankshaft oil seals just so I've got them on the shelf should I need them.

It is an astonishingly smooth engine for a twin, that really surprised me.

[demag]

Would the brakes be standard components off something like mini?

[Zelandeth]

They're 7" Girling drums - I *think* the main user at the time of this exact configuration were Reliant, though it's entirely possible they were used on BMC kit as well.

Here's something you'll enjoy having a read of Jim...

Invacar Service & Repair Manual

...The uploading of which has demonstrated to me that my server has for some reason lost all interest in running the FTP daemon...That'll be a task for tomorrow then...

[Michel]

They're 7" Girling drums - I *think* the main user at the time of this exact configuration were Reliant, though it's entirely possible they were used on BMC kit as well.

If they are the same as the Robin of that era, they're simple to work on. My grandad always had Robins and I did the brakes on it more than once as he always took it to the garage where I helped out in school hols. In the unlikely event they baffle you I'll gladly pop up and see if my memory is jogged.

[Zelandeth]

They look a simple enough setup so I'm not *expecting* any problems. It's pretty much a perfect example of a textbook "here's what a drum brake looks like" really. The only real downside I've found so far is the size of the hubs making getting the lower shoe return spring onto the second shoe a real pig of a job.

[CitroJim]

Those springs are always a pig of a job whatever the size of the hubs Zel...

A good old-fashioned spring hook is what's needed and something like this may fit the bill:

Amazon.co.uk

And this is the link to get one:

https://www.amazon.co.uk/Sealey-VS0351- ... pring+hook

Great value at £6.99..

[Michel]

Let me check in my toolbox. Might have a brake spring putter-onner that I bought for the DRK but never used as I ended up using pointy mole grips and brute force.

[van ordinaire]

Never knew there was such a thing ord, indeed, had it occured to me that there was an alternative to wrestling with a pair of pliers, 'til I read something on a Cherokee forum relatively recently.
Apparently there's also a tool for dealing with the shoe retainers (except Morris Minors) whereas, again, I've always struggled with a pair of pliers but, on the Cadillac forum I learned how a strategically drilled hole in the jaws will, effectively, produce a tool that could've been purpose made for the job.

[Zelandeth]

Interesting. I did come across a tool not unlike that at some point in the past, but never twigged the intended use at the time. There's just enough give in these springs that it's merely "annoyingly fiddly" rather than something which really requires purchase of additional tools - especially as purchase of a proper tool storage solution is far higher on that priority list just now. My current toolbox while ideal for mobile use, is just too small for the garage these days. Especially with the new arrival meaning that a decent set of imperial spanners will probably be added at some point. I doubt in reality that I'll be needing to take the drums apart all that often anyway.

Decided to take a day off the brakes today - mainly because I haven't yet figured out where my brake pipe flaring kit has got to, and I'm starting to think it may well be one of the items that I had to leave behind in my father's shed when he moved house.

So instead I did a few other things:

[] Firstly was continuing to piece back together my poor mutilated excuse for a wiring loom. Stage one of this involved employing some cable ties to convince the wiring to the starter solenoid that rubbing against the offside rear wheel was actually a bad idea.

...This will obviously be less of an issue once I actually have rear wheel tubs. Really do need to start thinking about bodywork soon. The two bowden cables you can see there should also control flaps in the heater box which should be in this area too. I still need to source that from somewhere - or fabricate my own.

Next up was starting to attach some of these bits of dangling spaghetti to each other.

This is made *slightly* more interesting by virtue of the fact that in the three years between the launch of the Model 70 and the production of mine, that some of the wiring colours have changed - so they don't all match the diagrams. It's also possible that the manual is referring to the Invacar rather than AC version of the Model 70...They're actually two totally separate things made in two separate factories, albeit as part of the same supply contract essentially to the same design - though there are some differences under the skin.

I had a look at transferring the indicator stalk assembly from the spare handlebar assembly over to the car, however got defeated by a stripped out screw head. Oh...and discovering yet more snipped wiring (yay!). I need to have a look tomorrow and decide whether it might be easier to just transfer the whole assembly over as it stands rather than trying to remove the indicator assembly from the spare handlebar assembly...

A lot of the lighting circuits and such pass through this though, so I'll need to get it reconnected before I have any hope of getting life out of those systems. Plus once that's done I *think* it should mean that all of the snipped wires actually inside the car will be accounted for - and that's a milestone I'd like to see passed.

[] Drive assembly. I did spot something on the gearbox that may need some remedial work today. It appears that what I assume is a cooling fan attached to the back of one of the drive pulleys has started to break apart. It's a thinly made pressed assembly by the look of it and simply hasn't stood the test of time. The lack of rear wheel tubs meaning that the area has seen far more weather than the designer probably intended won't have helped.

I'm currently waiting for some feedback from a couple of people who know these vehicles better than I do as to whether this is something I actually need to worry about, or whether it's a case of "they all do that, ignore it."

[] Next up was getting it run up to temperature so I could do another oil change. Contrary to last time I started her up (when Jim was visiting), when it was an utter git to get going, today she started instantly and on both cylinders without any messing around whatsoever.

The backfiring issue seems to be something that is getting better with use. I did dump a heap of carb cleaner down the intake today (something I try to keep to a minimum as I know it's a very effective degreaser and I don't want it removing too much of the oil film in the cylinders), and it definitely did something. Most obvious by the fact that the first application just resulted in the expected misfire and drop in revs, the second however resulted in a huge cloud of soot exiting the exhaust. I'm not entirely convinced this problem won't solve itself with the engine having a really good run at speed rather than just chugging around at idle.

The oil that came out was way better than what was originally in there, but still came out looking pretty black. I'll change that out again as soon as it starts to get visibly darker.

[] The thought that I'd never actually checked how much air was in the tyres crossed my mind today...rears weren't actually too bad. However it's quite noticeable how much easier to move it is now that the front tyre has the required 17psi in rather than 3!

Speaking of tyres...anyone able to translate this into modern tyre dimensions for me, as I believe this is the correct tyre size that this would have had from the factory.

Finally here are a couple of things I meant to show you while you were here, Jim!

You asked where the Dynastart actually lived - here's the answer. Directly coupled to the hub of the cooling fan behind the stator.

Finally was something which surprised me - the sheer size of the oil cooler.

The only other air cooled engine I've spent any real time around was the 1600 CT engine on the VW T25 I had for a while. I'm quite familiar with the concept that air cooled engines shed a lot of their head via oil cooling, hence the fins all over the sump as well as the cylinder barrels and heads and the fact they almost always also have a separate oil cooler. The VW had 1600cc and four cylinders to cool though, yet the AC has an oil cooler which has nearly double the actual surface area...Cooling systems designed with decent overheads in mind? That's a design decision I like!

[daviemck2006]

I would say 145x10 is the modern radial equivalent of that Zel

[van ordinaire]

I'd agree with Davie's tyre size conversion BUT as the only 10" car tyre is the original Mini one it might not matter - however THEY are 145x10's.

You're welcome to my duplicate imperial spaniards, including a small, hex drive socket set that might appeal - although I don't anticipate being in your neck of the woods 'til April.

[Zelandeth]

Thanks both of you. Does indeed look like 145x10, 145/80R10 or whichever convention for writing that is correct. Vintage Tyres list the exact Camac ones that are on the back for £40 each, so that's probably what I'll wind up going with. They'll look the part at least.

Much as I'd love the Dunlop SP Aquajets for their looks...and knowing it's a properly period design...at £100 each, not going to happen!

These started out with 12" wheels, but switched to 10" in 1973 apparently. So probably were using exactly the same rubber and wheels as the Mini. Given the parts bin raiding that went on when this thing was built, it would make sense.

I'll certainly happily give any imperial tools that are excess to requirements a home...as I get the feeling this thing will be sticking around.

[CitroJim]

Zel, another excellent instalment!

I have a brake pipe flaring kit and a lot of cupro-nickel pipe here so no need for you to go out buying one...

That oil cooler is massive! and the dynastart is a lot smaller than I expected...

145x10 was definitely Mini... In theory you could put a front disc on the front - one from an early Mini Cooper...

[Zelandeth]

May well take you up on that Jim. On the plus side, there really isn't much pipe involved! I'll see if the existing pipework will play nice and come off intact so it can be used as a template to make new ones. I seem to remember from when we looked at the underside that quite a lot was okay, so might even just be the one branch that needs replacing.

I reckon a disc brake on the front wheel probably would be superfluous really, it's so light that the drums should be more than up to the job. Too much braking effort is just going to cause lock ups - especially on the front.

I guess the size of the oil cooler is a bit of common sense really given the origins of the engine and its use in a lot of more industrial sort of applications. Running flat out all day long and general neglect are probably more factored in there than in most car designs (2CV possibly excepted there).

[Zelandeth]

Didn't really have much time for car things today, but had a quick poke around as I'm determined to keep on getting at least something done at least every other day.

First up was the fact that it had come up in conversation that my battery was actually in the wrong place - so goodness only knows that that bracket in the footwell is actually for. The battery should live in the engine bay on the nearside, just ahead of the ignition coil.

The evidence does seem to bear this out - especially if you look at the length of the positive lead to the starter solenoid - it's perfect for the battery being somewhere in this general area:

This mark on the chassis leg I'm guessing is the remaining evidence of the existence of the original battery tray.

This item, located in one of the boxes I'm guessing is the clamp intended to actually hold the battery in place...

So I'm waiting for some feedback from other owners as to what form the battery tray actually takes so I can start looking for one or fabricate one.

I then had a quick shot at removing the rigid brake lines - only discovering that I need an imperial size spanner that I don't have for that. That can wait until next week.

Instead I turned my attention to refitting this. After I wasted half an hour wrestling the front half of it off the spare dash.

Silly small detail I know, but the hole in the dash was making my teeth itch!

Another ten minutes of standing on my head had it making this happen on command.

...Tiny details, yes. In the grand scheme of things though it's still one more item off the to do list as it needs to work for the MOT.

Note to self: If you have to remove that again...reconnect the pipes to the pump *before* you attach it to the dash.