1973 AC Model 70 Invacar, Visitors & Occasional Distractions

Heat is provided very similarly to on a 2CV, there's a port that bleeds off some air from the engine cowling, then an exhaust to air heat exchanger and a duct from there to the cabin. There's plenty of heat, just not much airflow - so I'll probably block off the original port on the cowling and fit an electric fan.

The engine to my ear sounds like a very angry 2CV...

Quite a few of the engines from these wound up in 500s when they were scrapped as they're quite a bit more powerful than the original Fiat engines, but are a straight swap as the prototype used a Fiat unit. The easiest way to get a couple of extra horses from the 493cc one is dropping the slightly larger carb from the 600cc version to improve breathing a bit. From what I've heard though the engine shouldn't be struggling from a performance perspective "out the box" anyway. 20bhp and 410kg compares pretty well to the power to weight ratio of a 2CV and they seem to manage just fine.

I'm not a huge power seeker these days...the van has shown me how happy I am to just bumble around and enjoy the journey...plus if I do want to go quickly that's what the Xantia is for.

Bookmarked, i follow Ian's channel (Hub Nut) so have seen this giving TWC (Ian's Invacar) her engine.
I briefly saw TP in the video of the FOTU last year too.
Good to see that TP is alive again after the years she's sat. Good save, keep the updates coming.

To be honest I've been really lucky.

When I got KP, despite the body being largely missing the engine had been running (relatively) recently. All I had to do to get it going initially was some wiring and to unstick the piston in the fuel pump. Beyond that several oil and filter changes and a really good clean of the cooling fins and the carb have been pretty much it.

So by the time TP arrived in my driveway I already had an engine that I knew was fundamentally sound ready to drop in. Plus I'd already had the brakes and everything on KP apart, so I knew what I was doing when I came to do the same jobs on TP. Between that and hearing some of the pitfalls that had been encountered in TWC's resurrection there was a good deal of time saved.

To be honest she's been a pretty co-operative patient really. There's been very little in the way of *really* stuck fasteners or anything like that, and to be honest it's a pretty well thought out vehicle and as such is quite pleasant to work on. Today's swear fest adjusting the CVT belt tension was the exception rather than the rule. I get the impression that it's a job really intended to be done with access to a ramp.

The fact has to be kept in mind as well that she's going...in so far as I've driven around the block a couple of times. There's a big difference between that and hurtling across the countryside at 50mph with any degree of reliability!

This is the point at which more technical gremlins are probably going to turn up and be more challenging to sort.

My hope is that I'll be undertaking quite the grand voyager in this car probably next year - so reliability is definitely a target I'm striving for.

Oh - and yes, I fully intend for her to be at FotU this year too. Not sure if TWC will make an appearance there, but it would be good to see them both there.

I do enjoy the fact that both of these cars have been given a second chance though, have to wonder what the odds would have been on them ever having a future this time only a couple of years back.

Sidetrack...



Tell us more!! Do you have a thread on these anywhere? (I had a quick look for threads you started on here, but nothing jumped out at me).

I am ashamed to admit that when I used to see these around my local town (Menai Bridge and environs) in the late 70's/early 80's I was disparaging about them (and the occupants). Awful attitude then (upbringing? taking on my parents thoughts? boarding school attitude? all of the above?) and really not very proud of myself.

But am prepared to admit it, which is something I guess (or is it? often wonder).

Anyway - moving on if i can - v interested to read about it, read about how elegant a solution, in engineering terms it is and the remedies you're making to it. I also like the dedication to keeping it as original in look and feel as possible (the tyres) too.

And is the xantia active as good a handler as they say it is? or is there more to it than that?

Task number one for today was to get the offside brake light working again as I noticed yesterday when I got back into the garage that it was out again. This eventually turned into a 45 minute round of chasing my own tail before re-terminating the main ground for the cluster as I should have done in the first place - which of course immediately resolved the issue and also got both sets of indicators to flash at the same rate for the first time.

Task number two was to cover up some of the bare metalwork on the rear of the car. This has wound up with the whole thing encased in duct tape for now, looks horrific, but at least there are now no sharp edges accessible. I'm sure a bunch of these cars were largely held together by gaffer tape back in the day too.





No, I'm not proud of it. It's a means to an end - I want to drive the thing, and don't want to wait until I can put aside a couple of complete afternoons with decent weather to attack it with fibreglass.

The offside front corner has had a steel band added to reinforce it, and has been similarly plastered in tape. I've also stuck a patch on the hole in the roof primarily to assist in keeping the weather out.

Speaking of keeping things in or out, I'm glad to see that the lock on the front service cover has freed up after a couple of months of regularly dosing it with penetrating fluid.



Nice the way stuff seems to keep coming back to life.

With this all done it was time to go for today's test run. After a little noodling around our estate again I decided that it was time to try the higher speed run. No horrors to report. Managed to get up to just under 50mph before having to brake for the roundabout at the bottom of the hill. On the way back progress was slowed a bit, but still got up to 40 or thereabouts. The only slightly unnerving aspect was that she briefly decided not to give me any power when I intitally went to pull onto the roundabout coming back - a fraction of a second's delay and audible pop back through the carb and she was off again. I've notice this happen a few times on roughly half throttle. Guessing there's still a bit of crud floating around in the carb.

On arriving back from that run (wanting to give thigns a check over given it was the first time she had exceeded 30mph in quite a while), there was quite an odd "hot" smell - which I reckon was coming from the paint on the silencer after a bit of checking. The popping back through the carb I reckon is the reason that the carb itself was damp with fuel.



The carb being cold I think was the only reason this hadn't evaporated pretty much as soon as it had ended up there. I'll keep an eye on this.

I then went about a little further local testing, getting a little more used to the controls meant that a certain degree of mild hooning may have taken place. It's a long while since I was last in a Reliant, but to my mind this definitely feels less tippy when you throw it into a corner or roundabout.

I did attempt to get some video footage of the test drives - but managed an epic fail today on a video front. Attempt number one went just fine until the first roundabout was taken at any speed...at which point the phone fell out of where I'd wedged it. Attempt number two would have been fine if the phone hadn't wound up pointed mostly at the ceiling. I'm going to try to dig out the Not-A-Go-Pro tomorrow and use that instead as it at least has some proper options to secure it to the car. If you guys want me to upload the video I do have just let me know...You can kind of see what's going on and have the audio to go with it.

So, stuff I've ascertained today:

[] Oil leak from dipstick might be fixed.
[] The grounding arrangements in these tail lights is epically rubbish. I may wind up improving this myself to save me trouble in the long run.
[] Handling is better than I expected. I reckon you could actually chuck this car around quite a bit once you're used to it.
[] On the same topic, the suspension and steering feels really tight. No knocks, clonks or obvious play in anything like that.
[] Ride is pleasantly compliant, bit of a surprise given how light she is.
[] One horrible noise which has turned up a couple of times is the guard touching one of the pulleys very lightly - mainly just as you come off the throttle. I will sort this using a small amount of violence shortly. I know what it is though and it sounds way worse than it actually is.
[] 50mph looks to be doable without too much trouble.
[] Occasional miss/backfire on part throttle needs an eye kept on it.

I needed to go to the nearest supermarket for one or two things this afternoon and very nearly took the Invacar...Sadly I chickend out. Maybe tomorrow.

Definitely overall seems to be running better. The drive system seems to be behaving itself pretty much as I'd expect now, I think the biggest thing which initially was throwing me off is just the level of overall noise involved with the engine running at the speed it needs to for the clutch to engage. Was really glad to see that once up to speed that there weren't any unpleasant noises or vibration which would suggest duff wheel bearings or any boring problems like that needing attention.

Paint the tape blue - its as good as fixed !

"I then went about a little further local testing, getting a little more used to the controls meant that a certain degree of mild hooning may have taken place. It's a long while since I was last in a Reliant, but to my mind this definitely feels less tippy when you throw it into a corner or roundabout."

If you can get yourself stopped for driving furiously in one of these by the dibble you would have reached a new level of epic !

Ref the fuel leaks and fibreglass have you got a fire extinguisher on board ?

Videos would be nice but don't crash getting them !

James

Used to see a garage and yard full of these near the old Poppet factory on the way to Croydon back in the day, always fascinated me until one day they were gone. A disabled lady that worked in the local knitting shop my mum frequented had one though and was well known for being a bit " throttle happy" and being constantly followed by a blue cloud, mind you it would never have turned over as she must have weighed thirty stone, good old Mary.... I think these probably started my love of all things three wheeled. Miss the Isetta and the Regals but have kept hold of the Bond Bug. Following this with much interest.

Today has been something of a "one step forward, a few hops sideways, and one backward." We knew there were going to be some of them, that's the whole reason we're doing the VERY local shakedown runs. Which I'm sure are really annoying my neighbours by now.

First up, I did managed to track down the Not-A-Go-Pro and do a test with that stuck to the rear window. Annoyingly, while the video is better than I've managed from my phone - the microphone really didn't enjoy such close proximity to 493cc of thundering power behind the driver's seat in the Invacar, so I must apologise for the horrible audio distortion.

YouTube Video over here.

This really does seem to make the ride seem a lot firmer than it feels in person, but better captures the degree of lean when cornering. At least around town you don't really notice the lack of a wheel up front. Until you come to park up at a kerb...the lack of a bump from the nearside front corner the first time I pulled over at the side of the road, *that* messed with my head.

I hadn't spotted until viewing that video that the nearside indicators seem to be playing funny business again...Yay...Those tail lights are going to be a recurring problem aren't they...

The free play in the brakes looks way worse in the video than it feels in person, I think the angle and the lens exagerrates it a bit. There's a good 2" of clearance between the point at which I can lock all three wheels and the bars hitting my knees. I managed to get the single carriageway down the side of our neighbourhood clear a couple of times today, so was able to do an emergency stop from 50mph, and am pleased to say that she can come to a stop more than adequately rapidly when needed.

When I got back from that run, with an even five miles on the clock I decided to check the condition of the plugs just to give me an idea how the engine was running. It's worth noting that the one in the offside cylinder has always had a history of flooding quite regularly on startup, and had always been sooty when the car had just been idling on the driveway. This is how it looked today.



Here's the partner from the other cylinder.



Not bad at all I reckon, though obviously it's hard to tell too much from so few miles. No obviously catastrophic oil contamination or anything like that at least.

Today did unearth a few gremlins though.

[] Fuelling. It seemed today that after I'd been going for roughly 30 minutes (including three higher speed runs), I started to experience what felt like severe fuel starvation. Thankfully I was able to limp back home. This definitely shows why I'm doing things this way though, for all it might seem needlessly over-cautious to some folks.

I'm pretty sure that this problem is due to a problem with the fuel pump itself.

Looking at the fuel filter in the engine bay (between the fuel pump and the carb) you can see bubbles of air being pumped through along with the fuel. This is an absolute pain to try to catch visibly on camera.

Here's the best I could manage over on YouTube

A problem on the suction side of the pump really is the only cause I can see for this. The line from the pump to the tank is a single piece of new hose, and attaches to the bottom of the (full) fuel tank. I'd have expected any holes in the line to have therefore made themselves known by leaking fuel out overnight as there should be a decent head of pressure there. Top of the fuel tank is roughly level with the top of the carb.

Obvious question: Is there a vacuum issue due to venting problems? Nope...The cap is vented - and in fact the cap wasn't even on the tank when that video was snapped.

A rebuild kit is avalable for the fuel pump...so I think that will be my next stop.

I think a gasket set for the carb probably makes sense too...



[] Gearchange linkage fell off!

As I limped into the driveway on one-and-a-bit cylinders due to the fuel starvation issues, I applied the handbrake then suddenly found that my right hand couldn't find the gear lever for some reason.



Oh. That doesn't look right! Sure enough, pulling the rear service hatch out and standing on my head showed that the connection between the lever and the actual gear selector had come apart. Nice and "easy" to get at...



You may recall when I took this out of KP I was unable to extract the split pin from this linkage, so I'd put it together with a bolt and lock nut. Obviously this isn't up to dealing with the vibration etc, so I'll need to find a better solution. In the meantime I'll make up a new locknut and apply some threadlock to hopefully keep things together in the meantime. A long enough bolt to fit this position definitely needs to remain in the vehicle toolkit though!

It was nice to see that the pulleys do seem to be cleaning themselves up quite nicely though simply through a bit of use, and that the belt tension seemed to have remained exactly as I left it when I adjusted it.



While there's still some oxide left there visible, the surface itself feels far, far smoother than it used to. I did wonder if I should put more work into cleaning this lot up - but given that the drive system seems to be generally behaving itself I'm inclined to leave it alone for now.

[] Gearbox oil leak.

When reattaching the gear linkage it was hard to miss the fact that there was quite an obvious leak of gearbox oil from the top cover.



This wasn't a huge surprise to me given that the box was found essentially caked in a 1/2" thick crust of gearbox oil mixed with mud - what was a surprise what that all four of the nuts were barely finger tight...Let's hope that having nipped them up has sorted that. Failing that I don't think the cover holds anything in, so shouldn't be too hard to make up a new paper gasket if necessary.

Before I went out today though I set about trying to do something to make her look a bit less like a set piece from some post apocalyptic disaster movie, this basically meant trying to shift some of the moss and grime.

Attacking the doors with a stiff scrubbing brush and caravan & motorhome cleaner did a pretty decent job.





There is still some discolouration which I'll need to hit with some cutting paste, but at least it looks *slightly* less like it's just been dragged out of a field now.

I think thinks will probably need to take a back seat for a few days until I can get the parts for the fuel pump in. Sadly I don't have a suitable alternative pump, electric or otherwise, laying around or I'd test by substitution first. Obviously I can't really keep driving with a known fuelling issue.

What I might do is hook up the fuel injection pump I've got laying around drawing from the carb end and dumping back to tank - the flow level that should get going might allow me to use my eyes and ears to track down where the leak actually is as I'll probably be able to hear it hissing.

Annoyingly I'll most likely have to drain the tank down if I do need to dismantle the system...Methinks a fuel tap right at the tank might be a sensible upgrade...

Will take the opportunity to readjust the brakes again - I have my suspicions that the front adjuster isn't doing its job, so may well swap it for a known good spare and see if that helps. As I've said before, the brakes feel really good. Nice firm control and good bite, just a lot of dead travel before you get to the point that the control does anything.

Would have been nice to get a clean bill of health and just start driving places (as I'm getting quite comfortable with the actual act of piloting her now), but realistically we knew there were going to be things that would turn up and need sorting didn't we.