Handbrake

This again is more for my own benefit and possibly for Mr IVA man. As I spotted in previous work the cable for the handbrake meets in a deliberately confined space. This is for strength mainly, I needed to make sure that when I pull on the cable it actually operates.

The problem is that it might be too tight. With the cables and balance bar in place, it looks like this;

That doesn't leave much for tension. In fact, it's about 20mm;

Beyond that the handbrake will stop but the brakes won't apply any further. With the cable attached to the handbrake, I had a look at what sort of movement I'm dealing with. With the grey tape in the above picture being 'at rest', I applied 12 clicks;

That's around 17mm. Given handbrakes need to be on full lock with somewhere between 3 and 8 clicks, I should have plenty of space to operate. 

I will try all this once the calipers are actually mounted but I think it should work quite nicely. That's assuming I can adjust them correctly to start with to only need 17mm of movement.

Photos of current tasks

 These are pictures from the snag list work, partly to show what I've been up to but also for Mr IVA if he needs more visibility of what I've done.

Propshaft installed and nicely clear of fuel and brake lines, with new bolts and nyloc nuts for the diff end;

Fuel system plumbed in. Most of the connections were barbed or had a flange, so those got one fuel clip. The main run from front to back was just on plain pipe though, so those got two clips each end. 

The routing left two fuel pipes going over the edge of the tank which I'm not happy about;

As I type I'm 3D printing a bracket that will hold the pipes in place and I'll glue it to the tank. 

Front suspension all bolted up and tested for full lock, the brake pipe looks like it's floating but actually it works as expected, staying away from any moving part. Hopefully I can get the same freedom of movement on the back;

Steering bolted up;

As mentioned earlier in the build, the use of an exhaust clamp and slotted bolt holes for the top portion of the steering assembly is intentional and carried over from the fixings on the original MX5. The collapsible section of the steering column is between the two, so it's to allow the whole thing to deform correctly. If the driver hits the steering wheel the upper bolts will disengage, and if the steering rack is pushed up from the front of the car, the clamp will allow it to slide. On top of that there is still the ten degree angle on the UJ which allows for deflection on impact.

Snag list

Part of my job is being able to click a button and let the work do itself, so while my PC chugs away at something unpleasant, I thought a snag list would be a good idea. And yes, this is the home stretch now. I'll update this as I go. ;

(First edit 06/06. It looks to be stormy this weekend so figuring out what to do will be important here)

Brakes

• Fit calipers and pads on to already fitted discs. Now I have the bolts I can do that. Fronts fitted, rears to be bolted on.
• Fit braided lines. They're on but not tightened. They need the retaining clips added. 
• Check the pipe routing so it's not rubbing on anything. All sorted, they pipes are attached all over and really secure. 
• Fill and bleed brake lines, and check pedal effort. I'll do the clutch at the same time.
• Fit handbrake cables and adjust to working position. bit of a problem here, the brackets don't seem to fit and the balance bar hasn't got enough room to balance. I think I can dial both out once the rear calipers are fitted. Big progress on this one, see other post but essentially I've pulled back the two cables to give a lot more clearance on the balance bar. Just one task left, to fix and crimp the front cable. 

Transmission and suspension

• Fix the gearbox mounting bracket. I need to find the nuts for this one. Nuts (and bolts) found and secured. To be honest I seemed to just pick the right bolts first time, no idea how! The nuts are Nyloc but the bolts are the originals so I'm not expecting any issue. The main problem I had was getting the bag off the end.
• Fill the diff with oil and bolt in place. Yep, done. And yep, I'd forgotten how much gear oil smells. It was also quite entertaining wrangling the diff out of the cage and back in again. I'm hoping it won't ever have to come back out, particularly when I fit the boot lining (oh yeah, new snag).  
• Fit the prop shaft, bolting it on to the diff. I was dreading this, but in the end the only issue was a bit of corrosion on the faces. Once a wire brush had gone to town it all slotted in perfectly, pictures to be added shortly. It's left me a couple of mm on the front where it enters the gearbox, which I think is pretty much what it should be.
• Fit the driveshafts on to the diff and wheels. This task needs the car wheeled out, and that's not going to happen in a storm. 
• Bolt all the suspension parts together. Fronts are all done, rears are to be done when it's a bit dry. Same here, need some dry weather. 

Exhaust

• Fit the manifold gasket and tighten the manifold to the head. Failed on this one, turns out I can't remove the manifold without removing the exhaust! So while it's jacked up I'm not going to be able to do any exhaust things. Very done and rock solid, almost too solid but we'll see what happens.
• fit the exhaust gasket and tighten the exhaust to the manifold. Also done. 
• Fix the exhaust U clamps. Centre U clamp still missing, and another job that needs the car outside to get to it. 
• Fit and wire the O2 sensor. I can do this small job.
• Fit the shield. And this one. 

Fuelling

• Connect the pipes front and back. New pipes and barbs are not a pleasant mix, but everything is now hooked up with the correct clips. Pictures to follow, but it does look like I have an airtight system.
• Add fuel, check for leaks. Outside job as expected
• Run the car. Outside job as expected

Body

• Cut the front wheel arches as required.
• Fibreglass in the aluminium mudguards.
• Edge trim on the mudguards.
• Glue on the printed brackets and sliders for the bonnet.
• Glue on the gearshift gaiter so it doesn't become unattached.
• Bolt on the rubber tie downs on the corners.
• Paint the body (possibly).
• Reattach all the trim pieces (roll bar, seat corners, seat belt edges).
• Bolt in seats.
• Bolt in seat belts.
• Fit mirrors.
• Add boot lock strike plate. 
• Add boot lining (may not do this for IVA). 

Wheels

• Clean wheels
• Order new tyres
• Sand, paint and fit hub caps. I started sanding them today and they've gone pretty flat, so just need some paint. I did wonder whether there could be a version 2, but they're good for now. 

Other odds and ends

• Sort out right brake light holder, the bulb doesn't want to stay put
• Fit all the wiring braces
• Fill coolant
• Fit edge trim on the remaining sharp edges
• Make and fit pipe brace for the fuel pipes as they come over the edge of the tank. First version printed, but not quite at the right angle to glue to the tank. Will need a second print.
• Buy more bolts. As expected I've run out of a certain type of bolt. Given that I regularly reused bolts I'm not surprised the total number of bolts is lower than the actual required number. I've bought more M8 which cover many of the bolt sizes I need, I'll just have to make sure I have enough.
• Bolt up the steering. OK, I seem to be adding snags rather than clearing existing items! In any case, the steering is all bolted together and is rock solid. I had seen reviews of the UJ's saying they wouldn't tighten up, but I don't seem to have had any trouble. The only thing I had to deal with was an eventual slight misalignment in the top two bolts, but opening them up solved that one. 

Weekend update

 Not a great deal to report from this weekend, but it was a sunny day so I thought a few photos would be good;

Oh yeah, that was one thing I did, filling in the bodywork. It's got a few scars and marks on the body, mainly from the demoulding process but also a few knocks and dings over the years. I used some filler and wet n dry to get them looking respectable, there's a few more that I need to sand down but I think I got them all. Hopefully it'll be ready for paint soon. 

So what else was done? I replaced part of the wiring binding with corrugated sleeving, this allows the wiring to flex with the engine as it moves on the mounts. The binding was keeping everything far too rigid and it didn't feel right. A quick Q on Locostbuilders confirmed my fears, but also a suggestion on corrugated sleeving was very well received. Now the wiring to the engine is still flexible but protected.

The last few jobs are for small mounting brackets for the wires, these are printing behind me as I type. Nothing spectacular but at least they'll hold the wires in place better. I also cut some brackets for around the engine also for mounting the wiring.

I also cut the pipes for the cooling system, so now the main feed pipe gets to the globe tank as does the overflow. Hopefully that should keep airlocks to a minimum. I've got a few jubilee clips to add on that, nothing difficult. 

The bonnet fitting is now as expected, I adjusted the sliders to fit the bonnet so they ensure the bonnet closes smoothly and ends up in the right position. It turns out they're far too long so I've reprinted some shorted ones with better edge support. The last job for the bonnet will be the rubber tie down brackets that will go under the edge of the bonnet...

Or will they? I've just thought, I want to have them in the exact place that the sliders work! In fact, anywhere on the trailing corner of the bonnet is now 'out of bounds' for the sliders. 

Then again, the sliders do operate on the extreme corner and edge of the bumper, and that actually goes down alongside the body. So perhaps the rubber tie downs will be a bit further back along the bottom, and leave the slider along. Some time with clamps to position them correctly is on the cards I think. 

I do need to think about the forces involved in clamping down the corner. It needs to pull it tight against the bodywork, but end up in the right position. Maybe one more spacer is required on the bottom corner to provide tension for the tie downs. That could also double up with the sliders so it's two 3D prints rubbing against each other. I just need to make sure it doesn't get bound up when opening the bonnet as well as closing it. 

Apart from all that, I've got a load of nuts and bolts to find. They'll all be 'safe' but I need to find them. It'll be things like;

• Propshaft nuts and bolts x 4
• Driveshaft nuts x 8
• Brake caliper carrier bolts x 8
• Brake caliper bolts x 8
• Brake banjo bolts x 4
• Exhaust manifold nuts x 9 ?
• Exhaust clamp nuts x 6
• Exhaust manifold to exhaust nuts x 2

Guess what, more wiring...

 Well, the first bit of good news is that I got the fuel pump running. The key part was a missing ground wire. The main relay wasn't actually opening, and the output on the white red wire was 2 volts instead of 12. Given that anything that isn't 0 or 12 is bad (barring some sensors that need odd voltages), then 2 volts could only be something 'floating'. Lo and behold the black wire that I couldn't figure out what it was ended up being the ground end of the relay. Once it was earthed then the main relay switched on, which meant 12 volts going to the circuit opening relay. And when the other end of that connection goes to zero (which is the light green on the MAF) then the fuel pump kicks into life.

I was also able to check the spark, not with the spark plug tester though. That turned out to be a typical Chinese special that only served to pull the inner out of the spark plug lead! All I really needed to do was leave one of the wires off the plug and laid on the engine, that was enough to show a spark. 

So, spark good, fuel good (well, up to injectors at least) and compression... well, that's where I can't check anything just yet. 

Oh, a short diversion from electrics. I did my exhaust shield, and it worked really well. A combination of folds and rivets left it quite sturdy, in fact it was so sturdy I struggled to get it in the fender!

As expected it needed a little under two sheets, so rather than having one full sheet and one 'sliver', I joined them in one piece then cut them both so the seam ended up in the middle. The brackets worked well on a cut piece of exhaust too;

This left me with a decent amount of gap between the sheet and the cat;

And on installation (after a bit more fettling) there is a gap on the outside of the shield as well;

I also had a look at the gap between the downpipe and the cat, to see if the gasket will fit. Turns out it's not actually too bad, with the largest gap being on the bottom bolt which will hopefully tighten up on the gasket without putting too much load on the exhaust. Of course, there is still the absence of flexi pipe that could cause problems, but one step at a time!

Back to wiring. With everything connected I went to town with the wrapping. I had a real nightmare moving everything six inches to it's final destination, mainly because of the big thick ignition wires. But finally I was able to bolt in the two fuse boxes and route the wires in the right directions. The wires are now bound for all of the lighting and instrument wires, and partly bound for the sensors. There's a few tight wires that are dictating the routing, but overall it's not too bad, at least from a routing point of view. 

There's a few more things I need to do though;

1. Finish the wrapping. Not difficult, I just ran out of energy before I could finish it.
2. Create some metal brackets to mount the wiring round the cam cover bolts. It's a similar route to standard, but there's an extra bit across the front. Some simple aluminium stock will suffice. 
3. I need to 3D print some guides for the wiring. At certain points the wires go round sharp aluminium, that's a bad idea even before Mr IVA man has a chance to fail it! It'll basically be some half round tube, fixed to a certain radius so not to stretch the wire. Then it'll be tie wrapped to the wires, and fixed to the metal. Since the other wiring brackets are glued in place I might do the same for these. It's just to get the wires round the sharp bits.
4. Under dash fixings. The wires need to be tied in place under the dash, nothing clever but enough to stop it moving about. Binding the wires together usually makes them stiff enough to stay in place, I just need to make sure they don't chafe. 

What's next? Cooling system, fuel system, braking system, exhaust, transmission. Lots of nuts and bolts, but hopefully not much in the way of problem solving. Then it's the arches and paint. 

Then maybe a road test?

(Monday update) It occurred to me that the extra ground feed to get the fuel pump running was also connected to the gearbox switch. Well, that's what I thought, a quick Google suggests it's the other one. It's a pretty simple circuit, Black Yellow from the meter fuse goes to the switch, and red green from the switch goes to the backup light. The main issue (apart from it's awkward location) is that the terminals are some strange thing that won't release, so it's going to be hard to test it. Still, if it buzzes out to the meter fuse, and the other end is the light, there's not really much to check. I did have a go this morning but with only five minutes to spare it was a bit difficult. 

(Later that same Monday) Turns out the reverse issue was just a loose plug, I hadn't pushed it on properly when I was binding the wires! What a muppet, at least I didn't have to do anything complex.

Next task, fuel pump

 One thing I missed from my wiring update was that the fuel pump is being very quiet. Also the radiator fan is being very not-quiet! The fan I'm not bothered about, there will be some swapped voltage somewhere that is causing the relay to click and run the fan. But the fuel pump is a worry.

The fuel pump should run off the circuit opening relay, via a blue red wire (the other end is a black earth). The circuit opening relay connects blue red to light green, which comes from the airflow meter. Again, the other end of the air flow meter connection is black earth.

But that's not all. It looks like that when the light green is dropped to earth by the MAF, the white red into the circuit opening relay is fed on to the blue red. That's what makes the fuel pump run. 

So in theory if I ground the light green with the ignition on, the fuel pump should run. So that's one thing I can check.

According to this article https://www.miata.net/garage/fuelpumpdiag.html there's a few things to check on that route;

• Main relay clicking on when I turn on ignition. There is a click but it could be the fan relay rather than the main relay. Should be an easy check with a screwdriver to feel the click though.
• 12 volts to the fuel pump. Sounds simple enough, but I'll have to do it from the connector rather than the rear of the car as my arms aren't long enough. Apparently it should be 12 volts on crank and then for 3-5 seconds after.
• Add a jumper between fuel pump and ground pins on the diag connector. Since I don't have a diag connector this could be a challenge, however all it's doing in reality is grounding the light green wire which I can do as I have intimate knowledge of most of the wires on the car!
• This is where it gets a bit weird. It talks about 4 wires, with red blue going to the fuel pump and light green to the ECM. The other two should measure 12 volts DC, but by my reckoning that means white red from the main relay, and violet from the stop fuse. But where is the fifth wire, the black? Maybe it's not included? 
• The green wire should connect to ground when trying to start the engine, if not and it shows 5 volts when measuring voltage, then the ECM is toast. 
• Of course the last test is to apply voltage direct to the pump to hear it run, so that I can try as well. 

(Later that same day). So I didn't get much time in the garage (the new job is hard work and being tired in the garage never seems to be a safe combination), but I did check the main relay and it was clicking, but the injector relay wasn't. Opening the MAF flap didn't appear to wake things up either, so now I'm on to buzzing out wires and checking voltages. Just checking on Ebay a replacement ECM is around £70 (B63H is the search term apparently), so while I hope I've not blown anything up (not expecting it at this stage) it should be pretty easy to get a replacement. 

Oh, and I had a suspicion that in my dim and distant past I'd bought a spark plug tester, and just checking my toolbox I have indeed got one. So I'll also check spark while I'm here to see if that is ok. 

Exhaust trim

 The other job for this weekend was sorting the exhaust. It needs three tasks;

• Adding the exhaust end trim to make it IVA compliant.
• Adding a heat shield round the cat so it doesn't melt the fibreglass body or the passenger.
• Ensuring the gasket faces are aligned to reduce leaks.

The third task here was the last thing to do, and I need to bolt up the manifold properly first to have any chance of getting things lined up. So it's not included for this weekends work.

First thing was the exhaust trim, and it started badly. I don't know what the trim was made of, but it wasn't ferrous and it was as thin as paper. It was also the same thickness as the exhaust, or at least that's what I initially thought. A quick visit to the nearest car place gave me some ideas on what to do, basically an aluminium sleeve over both sides, rivetted in place and with some exhaust paste to make it airtight. The airtight bit wasn't vital here, it's right at the end of the exhaust anyway. The emissions test probe would go in further than the join so it's not as if I'm cheating the emissions test. 

That's where it got a bit weird. Cutting both the exhaust and the trim to length I found that the exhaust got narrower. So narrow in fact that the trim piece actually slotted over the exhaust! Of course, at this point I'd cut them both to length, so having it slip over wasn't a good thing at this point.

Having said that, it did still work, and refitting it to the car gave me a good guide on how much it would stick out. IVA has a certain limit, and aesthetically I wanted it peeking out every so slightly anyway. So I continued with the same job, although I used hose clamps rather than rivets. I may swap those out in the near future, but they're not visible anyway.

Once the body trim piece was positioned and screwed in place, I think it's come out really nice;

The fixings aren't visible, and it has just the right amount of 'peek' to be what I wanted. I particularly wanted the slight angle on it, I think if I'd have tried to go for 'perfectly aligned' I'd have never got it right and it would have looked worse just being slightly out. At least this is purposefully at an angle. 

Unfortunately the deviation from the initial plan killed several hours of useful time so I wasn't able to get to the shield. However, using the hose clamps on the above does show how I can do it. The cat isn't that much thicker than the pipe itself, as shown in this aerial photo;

So my plan of using aluminium brackets rivetted to the shield, then hose clamps front and back of the cat will allow me to fix it well. I might add a couple more brackets mid point to keep an air gap between the shield and the cat, but they won't need to be fixed. Then again, just thinking about that I am wondering whether having unfixed brackets will give me a nice 'buzzy' sound on the exhaust when it's running. Perhaps just front and rear brackets then. I could put a crease in the shield, that would increase rigidity considerably. The size of the sheets means I need two side by side to cover the length of the cat, but I have some capacity to include some folds either side. Just checking the hose clamps show they'll work well, if a bit fiddly, and there's definitely scope for folding. 

Oh, and there is the centre section of the exhaust trim that I'm still not convinced about. It can still be removed, but for the time being I'll leave it in. Again I'm not going for a race car so I am assuming the reduction in size isn't going to be a major influence on performance. 

Major milestone

 It was a big event on the weekend, the completion of the wiring. Well, the connecting up at least, I've still got to tidy it up and correctly fix it. But I have a functioning car, all the lights work and it looks great.

Of course, there were issues;

• The stop and brake lights were inverted, I had the brighter light showing as the stop light. Simple enough fix, just swap the pins on the connector.
• The drivers side light bulb is popping out again. Well, I think 'again' because it's the same problem I had before that prompted the 3D print of everything. First thing will be to replace the bulb with one of the Lucas bulbs I bought, if that doesn't help then I'll make it a more permanent fixing. I'm hoping it may need maybe one or two new bulbs in it's entire lifetime so it shouldn't be too bad. And if I wreck the housing I'll just print another one!
• The headlights were also reversed, main beam was normal and vice versa. Again, two minutes with the wires swapped over on the bulb holders and it was the right way up.
• The hazard switch is 'temperamental'. This is annoying, as the holder is specifically printed for those switches and going on the hunt for replacements on the weekend just showed they were a different size. I'm going to open up the switch again and see if I can get it working better. 

On the plus side, the gauge and tell tale lights worked perfectly;

The tell tales are nice and bright, they're the right colour (even if they don't show well in the picture) and they all light when they're supposed to. The gauges are lit really evenly, the needles light up just as they're meant to, I even get a footwell light that I wasn't expecting! Of course, the latter is something I need to look at, while I quite like it I suspect there might be an IVA rule about it. 

Talking of IVA, I found my headlights don't turn off with the ignition key. I wonder if that's standard MX5 behaviour? Checking my wife's Mazda 2 it seems to do the same for her, albeit with a buzzer reminder. I'm going to have to be careful with that one, it's completely opposite to my daily driver Superb where I just leave the lights turned on all the time!!

Towards the end of the wiring I was missing a black yellow, so in front of the TV on Saturday night I decided to tidy up all the unused wires and arrange them. For reference, this is what I didn't use;

(And yes, I did find an appropriate length of Black Yellow!).

So all the lights work, and the engine turns over. Oh yeah, on that subject I didn't expect the car to start (there's no petrol in it for a start!), however I did observe a couple of things. First the fuel pump didn't run. I know the MX5 has a weird system where the fuel pump doesn't run until it's needed (and means MX5's are slow starters), but for it not to fire at all is a bit of a worry. I need to check voltages and connections on that. 

The other thing was the engine movement. It's able to move quite a bit on the engine mounts, which is a good thing from a comfort point of view (I'm not building a race car here), but even so with no load I didn't expect it to lurch from side to side so much. I'll have to see what happens once it fires up, to see if it smooths out.