Wednesday, 26 August 2009

Where to put oxygen sensor?

This is the oxygen sensor from the MX-5:

but where does it go? I though it went in the exhaust manifold but there is a blanking plug there:

Posted a question on the FM forum. Reply came back that it should go where the blanking plug is!

Fuel pipes - rear

It'll be obvious from the photos on the previous couple of postings that I connected up the fuel filter and pump at the same time as installing the rear loom and fixing the handbrake cables. Here is how everything looks from underneath:

The only things outstanding are the connections to the fuel tank itself.

Tuesday, 25 August 2009

Fixing Handbrake Cables

Used a bit of old hose from the MX-5 to wrap around the handbrake cables where they are tied to the suspension:

Making a good earth connection

Several build diaries comment on electrical problems due to bad earth connections. How to make a good earth connection? Although the thread on the bold should be good enough we decide to remove the power coating where the earthing terminals go. How do you make a perfect "bald" spot...
- take 1 rivet
- put a scrap piece of rubber on it (in our case from an old bike inner tube)
- add a washer
- another scrap piece of rubber
- a small cut out disc of emery paper
- put in a drill (we used a pencil to hold the rivet so we could get the drill in):

The purpose of the washer is to have something firm to press the emery down. The purpose of the 2 pieces of rubber is to stop the washer and emery from rotating on the rivet.

and you get a perfect "bald" spot:

Rear Loom

Modifying the rear loom wasn't that difficult but it took some time and patience to remove all the old tape and wires that were not required. It's a bit daunting looking at all the wires and I was quite nervous about cutting them as I didn't want to have to extend them later.

One thing I did do was consolidate the 2 plugs at the front into one. By the time I'd removed all the wires that weren't need they looked like this:

Smaller plug (left in picture):
Blue/red - fuel pump
Yellow - fuel tank sender
Blue/black (thick) - fog
Red/black - side light (splits into 3: RHS; LHS; number plate light)

Larger plug (right in picture):
Green/black - LHS indicator
Green/white - RHS indicator
Red/green - reversing
Green - brake (splits into 3: RHS; LHS; high level)
Red/white - door switches (I re-used this for the handbrake as it had the same type of connector)

Although the plugs are different sizes, the pins are the same so I was able to move them all into 1 plug:

I did remember to do the same to the corresponding front loom plugs at the same time!

To cover the loom I used self amalgamating tape. So far it seems to give a very nice finish.
I'd already attached cable tie fixings to the inside of the transmission tunnel and around the rear suspension before fitting the propshaft and diff.

Front end. You can see the red wire going to the handbrake:

going around the diff. This photo makes it look like it runs close to the diff plate but there's actually plenty of clearance:

it runs round the diff and above the drive shafts before going down to by the fuel pump. There it splits with one spur going to the RH:

In the centre of the rear there are 3 spurs
- a very short spur to the fuel pump
- a longer spur to the top of the fuel tank for the sender (which I was able to measure and cut accurately by a temporary fit of the fuel tank)
- another long spur for the number plate light (I don't know exactly how this fits so I used the length in the manual)

and this is how the back end looks all wired up:

All ready for the fuel tank to be fitted.

Threadlock & torqued nuts

Mike was up for the weekend and had some threadlock with him so we took the opportunity to torque up a couple of things:
- Rear brake callipers
- Propshaft to diff bolts

The front brake callipers will also need threadlocking but I'm waiting until later as the cycle wings attach using the same brackets.

New hub nuts

I'd removed the hub nuts while dismantling the MX-5. The old ones were fairly bashed around as I'd been hammering them to try to get the hubs off the drive shafts (and failed). I got new ones from They needed to be torqued up really tight and staked:

Pipe padding

The straight section of the lower pipe from the radiator was very close to the chassis and I expected it to knock when going over bumps in the road. I used a piece of spare cooling hose from the MX-5 as a bit of padding:

Fan fitting - a bit tight

The fan doesn't slot in between the radiator and the chassis so it's worth sorting out where it goes before finishing fitting the radiator fitting.

The manual states you should use 11mm spacers for the bottom. Nothing like that was in the kit so I cut down some stainless tube I had. When I put it in place there were a couple of things I found. The first was it fouled the bolts holding the nose cone in place (see posting below) so I changed those:

Second was the top bracket pushed the fan too close to radiator (it was touching).

I had 2 options: either re-bend the top bracket or move the radiator forward slightly. I selected the 2nd option for 2 reasons: firstly I had some plastic spacers that I could use to move radiator and secondly it meant the lower hose would have a little more room to clear the chassis:

The one risk is that when I come to fit the nose cone the radiator will foul the bodywork. I've seen in a couple of build diaries people have had issues when the radiator has moved forward but they moved it far more than the few millimeters I've moved it.

I also decided to rivnut the top bracket rather than rivet so that it would be easier to remove later if needed. I didn't have any M4 rivnuts so something to do later.


Rivnut tool time! I put a couple of M8 rivnuts in and re-used the same bolts that were used on the MX-5:

Nose bracket

At the same time as fitting the radiator I sitted the nose bracket. Initally I used standard hex head bolts but when I came to trial fit the fan I found they foulded the bottom of the fan so I replaced with these allen head bolts that had very small heads:

Radiator and cooling

The radiator went on:

this shows the pipe that goes diaganally from the top of the radiator:

this shows the diaganal top pipe as well as the lower pipe:

this is the lower pipe going into the engine (from the side):

the same from above:

and the lower pipe attaching to the radiator. This is right up against the corner of the chassis tube:

ECU Mounting Plate

Attached the ECU mounting plate. The hinges were attached by rivets:

The top of the plate was attached to the scuttle hoop by M4 rivnuts. That way I can get access to the ECU if needed without drilling out any rivets:

Light bracket - rivet

The brackets that hold the front lights are held in by bolts squeezing the surrounding bracket together but Westfield recommend putting in a rivet to make sure it doesn't come out:

Pedal Adjustment

The threaded bars from the brake and clutch master cylinders were too long. It meant that the pedals were too far back and couldn't be adjusted forwards (towards the front of the car). I had to cut approx 8mm of each bar so the pedals could be adjusted to the correct position. I've made it so the clutch pedal is just forward of your foot when it is on the moulded fiberglass foot-rest and the brake is just to the rear. I'll adjust later if necessary. It's good I'd not added the fluids as cutting without removing the cylinders would have been very difficult.

Accelerator Cable

Fitting the accelerator cable was simple after I'd found the old MX-5 one which still had the bracket that fits onto the engine:

Carbon canister

The bracket that holds the carbon canister is the one thing so far that I failed to save from the MX-5 that I needed. I though about fabricating something but managed to get one for £12 incl. postage from I was originally red (like my original MX-5) but I painted it black before fitting. I also used my new rivnut tool to fit an M6 rivsert for the sensor.

The chassis number is below the carbon canister but still fully visable which should make the IVA man happy.

Front Fuel Pipes

Fitted the front fuel pipes. Fitting the pipes was a lot easier than removing them! I also changed the spacers used to hold the rigid pipes away from the front panels. I'd originally used the platic corner blocks that are used on woodchip furniture as spacers. I found some nice black plastic round spacers which look a bit more professional:

Inertia reel seatbelt holes - covering

There are 2 slots in the back panel which are for the inertia reel belts to go through. As I'm fitting harnesses I decided to cover them:

Long Rivets

I'd had a problem with the standard length rivets when I came to connecting the fuel clips. They had to go through 2 clips (4 layers of platic), through the chassis and a washer (as I was riveting from the inside I has a washer to protect the platic from teh expanding rivet head). I got some longer rivets from RS Components. These are exactly the same as those provided by Westfield (4.0mm closed end) but longer:

RS Stock No. 351-3543
Manufacturers Part No. AD510SB
Closed end rivet,4mm dia 6.4-7.9mm grip
Price £4.31 for 100

These were prefect:

and while I was under the car I took another picture of the handbrake mod:

Speedo Cable

Attaching the speedo cable was again a trivial job that took longer than expected. The cable goes into the side of the transmission and there is almost no gap to the side of the transmission tunnel. It was a real fiddly job to get it in. I ended up having to have someone at the other end rotating it so that the centre aligned correctly. It's got a bit more of a bend in it than I'd like. I'll see how it goes. If there is a problem in the future I might investigate the right angle gears you can get that are designed to change the direction by 90deg.

Rivnut tool

I realised there were quite a lot of rivnuts I still needed to fit and although I could borrow one each time Mike was up it would be a good investment. I found the following on Amazon for £10.89:

It arrived a few days later. I'm sure if you were doing this sort of thing every day you'd want something more robust but it seems to be good enough for what I want.

Thursday, 6 August 2009

Handbrake Connector

When I connected the cable that connects the handbrake to the 2 rear cables I found it was too long. By tightening it as far as it would go I could still rotate the rear wheels. The solution was with Mike's friend Pete. He shortened it for me as follows:
- drilled out the original rivets holding the 2 plates together
- shortened the cable by approx 20mm
- removed the same amount of plastic coating (the plastic coating meant the new cable end was nice and clean - important for fixing later)
- cut off the shank from a bolt and drilled a hole for the cable
- drilled a wider hole in the rear
- fitted the cable through the hole and splayed out the strands of wire
- filled the wider hole with brazing
- fixed the 2 plates back together with a couple of new bolts and nyloc nuts
It was perfect when fitted. Correctly adjusted the thread is about half way up the adjustment nut at the handbrake end.
Thanks Pete!

here's the modified cable in place. You can see one of the new nyloc nuts. The new central bar with the cable running through it looks like the original but it's also new:

and here it is at the handbrake end:

Upper Steering Column - U bolt

The U bolt that came with the bracket for the holding the upper steering column wasn't really long enough. By the time it went through the mounting plate on the chassis there wasn't enough room for washers and nyloc nuts. The solution was to fabricate a new one.

Wednesday, 5 August 2009

Air filter

The M8 x 25mm dome allen bolts for mounting the "P" bracket that were missing and I'd asked Westfield for came through as standard bolts. When I tried them they fitted fine. I don't know why they specify the dome headed in the manual as there is no issue with clearance:

The lower section of the steering column will go right across the air in for the filter. I assume this isn't a problem. The MX-5 had a whole section of pipework for getting clean air into the filter which is not required for the Westfield:

From above:

Here is the re-fitted plenum chamber:

Not sure how I'm going to get the air filter and plenum chamber connected yet. Westfield don't provide anything. Most build pictures I've seen use flexible ducting. Here's the challange, I have to connect the 2 opening currently marked with masking tape. There are assorted bits of chassis, pipework and brakes in the way: