The wishbone therefore rotates on the poly-bush. This has two implications – firstly you can use bolts with fully threaded shanks, since the insert should not actually be rotating on the bolt. The thread of the bolt will therefore not damage the insert. The second thing is that the bushes need to be properly lubricated. This new set of wishbones gave us the opportunity to really pack in the red rubber grease. (Note – this does not apply to the shock-absorbers, which do rotate about the bolt). Many thanks to Chris for helping out with this sticky, icky job.

We got our engine mount brackets welded – big thanks to Ken of Zodiac Steel for assistance and doing such a good job. As soon as we had those sorted, we were able to properly see how the engine and gearbox would fit in. Needless to say, several adjustments to the bell-housing were needed, and we chopped some more bits off.

To fit the gearbox we needed to drill and fit the gearbox mounting plate. This is an H-shaped piece of steel plate, onto which the rubberised gearbox mount is, well, mounted. With the engine in place and the gearbox supported by a size-14 temporary mount, we could see if the mounting plate lined up with the mount points on the chassis. It was a wonderful moment when we realised that the fit is perfect. We marked and drilled the holes (8mm, although one was a slight miss, so it became a 9mm hole).

Feeling inspired by getting 3 out of 4 holes right, we marked and drilled the engine mount plates. We’d obviously improved our skilz, because we got 8 out of 8 of these right (no cheating here – 8mm holes for 8mm bolts, and they went in smoothly).

Checking the engine again, we realised that there was a risk that the starter would foul against the chassis. So it was another “engine out, attach part, engine in”. Only we realised a slight problem – the starter does not fit. There is a small sticky-outy bit on the sump that gets in the way. A couple of panicked phonecalls to Locost SA, and we confirmed that this needed to be chopped off.

It’s actually quite an easy job, but you don’t want to get all “power-tool” on it. The sump is aluminium, so if you get too aggressive you are likely to chop a hole in it. Another tool you’ll be needing for this job is a torque wrench that can handle 67N.m (thanks JR and Nick). The process is:

1) Remove clutch pressure plate (about 6-8 bolts, fairly easy).

2) Remove the clutch plate, to be left with the flywheel:

3) Remove the fly-wheel (6 bolts, fine thread), resulting in this:

4) Now you can get to the sump, and carefully cut the piece off. See pictures for confirmation.

You might need to remove two of the sump bolts, but we did not. You will not be able to use a normal hacksaw. A junior hacksaw got close enough that the last bit could be snapped off. Then a file neatened it up. One of those blade-only hacksaws will work, as will a dremel tool.

5) Clean off any loose shavings.

6) Put the flywheel back on.

Use a touch of lock-tite (removable) on each bolt, then torque to 67N.m. (Following all the right rules for tightening sequence. I tightened, bit by bit, a triangle of bolts, then chose the next triangle as starting from the opposite bolt that I ended on. Clear as mud?)

Leave the clutch and pressure plate off for now – they’re not needed for a while.

7) The starter motor now fits very nicely:

After this the engine went back in – we’re really getting our money’s worth out of that engine crane. The starter is a tight fit against the chassis, but it does fit. We then tested the bonnet for clearance – the dip stick handle will need to be “lightened”, but the 710 cap is fine (thanks to the bonnet scoop).

While we were fitting heavy things, we decided to balance it all out and fit the diff. It didn’t fit, which is a painful thing to find out while trying to hold that stupidly heavy piece of metal in place. The grinder was called to service again, but not quite vigorously enough. We actually think we might leave it as it is, since with a couple of spacer washers it fits fine.

EDIT 2011-02-25: It’s actually recommended by Locost SA that you rather grind away the webbing on the diff, than the diff mounting bracket. The theory is that the diff is more over-designed than the chassis mount point. We’re holding thumbs that it all stays together.

With the diff in place, it was possible to see how the gearbox and diff lined up. Badly, it turned out. The gearbox was shooting mortars clear over the head of the diff. Undismayed we put some longer bolts in the gearbox mount plate, and dropped it by about a centimeter. This lined it up perfectly, so we’re almost ready to order the prop shaft.

A small miracle happened during the week. We’ve been searching for ages for a solution to our alternator problem. We have a small, awsome little alternator from a toyota forklift. Unfortunately it comes with a v-belt pulley, not a 6PK pulley (which is used on the rest of the Rocam). Also, it doesn’t like high revs, and the test sheet shows its only able to handle about 6000 RPM for any extended time. The crank pulley on the Rocam is quite large, so if you put a small pulley on the alternator it is going to see some pretty high revs. This is NOT good, and others have mentioned burning similar ones out. So we want a big pulley which will fit the thing. The solution is a 6PK water-pump pulley, just like the one on the Rocam. If you attach this to the v-belt pulley, you are sorted. Well, we’ve been to several scrapyards looking for pulleys, with no luck. It seems you very seldom find a water-pump pulley separate from a water pump.

I posted for help on the forum (as I should have done first) and immediately found one pulley, and a suggestion to try Ford for spares. “Maybe they won’t be so expensive” – yeah right. So I got hold of Ford (it’s really worth telling these guys what you are doing, often they are very helpful) and I found out they do supply the pulley on its own. The price: r50 .11 ex VAT. I figured there was a number missing there – surely it’s R500.11? Nope, they ordered the part for me, and it came to R57 incl! Amazing. Even the guys at the parts desk were amazed (they showed me a much worse pulley for R900). The part number is XS6E-8509-AA if you want to find your own. I’ll post more info if it successfully gets attached to the v-belt pulley.

Our engine bay is now getting quite full, and we are becoming more and more convinced that the sequence we did the build in is just wrong. The brake and fuel lines really should only be going in once the immovable objects have had their say. As part of this blog I’ll put together a suggested build sequence.

Phew, long post! Till next time, happy building. Don’t forget, more build pictures here.

B

I can still remember, how that building used to make me smile. And I knew if I had my chance, that I could make that Locost…

Building has recommenced, after a break of almost two months. Sometimes one has to bow to the demands of the job. And when those demands take you to far-off lands, it’s tough to bring the chassis along with you. So it was good get the hands dirty and full of little splinters of metal. Ah, the joy of building.

We started with a visit to the scrapyard. Our outstanding bits include the yoke (connecting the gearbox to the prop-shaft), alternator mounting bracket and alternator pulleys. Hermann actually gave us a yoke, but it seems it’s for the smaller gearbox output shaft.

I can’t help but feel a little sad when going to scrapyards. Hundreds of engines, diffs and gearboxes all just lying around. Like organs for sale. Those once belonged to Daddy’s (or Mommy’s) pride and joy. They came home one evening, and said to the kids “come look outside”, and got all the “wows” and “hoorays” – Daddy has a new car. Now that pride and joy is an unidentified chunk of metal rusting on the scrap heap. And that’s not even contemplating the final act that may have caused it to be there. Sheesh, that got melancholic rather quickly.

Anyway, on a cheerier note, the visits were a complete waste of time. Scrapyard 1 was completely closed, despite a confirmation call the previous day saying it would definitely be open. The others had prop-shafts, but not exactly what we needed. The alternator mounting bracket, as well as pulley, were a complete loss. Then they all closed. We did find out (thanks Brad) that actually the guy who makes up the prop-shaft can typically source the yoke anyway.

For the afternoon we decided to sort out the fit between the gearbox and the engine. Previously we had machined the  end of the gearbox input to 10mm. However, the pointy bit is too long and must be cut down a bit. To avoid changing the steel tempering (hardness) we decided to cut this the old fashioned way – hacksaw. But first we needed to measure how much to cut off.

So we removed the clutch pressure plate and clutch. Then assembled the engine, bellhousing and gearbox. Remember to attach the bellhousing to the gearbox first, not to the engine. We knew this, of course. The photo is just demonstrating the wrong way to do it.

Now because our gearbox needs to have a bit chopped off, there results a gap between the bellhousing and the engine. We adjusted the various bolts to ensure the gap was even the whole way round (check with the vernier), and then took that gap as being the amount to remove. The whole shebang was disassembled and then the tip was lopped off at the right place (well, more or less). Be warned, that thing is made of hard metal. You’ll need a good quality hacksaw blade to get through it (or rip the teeth off a cheaper one).

A file was used just to neaten it up a bit, and we’ll probably give it a last touch-up with a grinder. A bit of water-paper to polish it up.

The reason for all of this is that unlike a FWD gearbox, the RWD needs to be supported in the crank. The crank has a 15mm hole in it, for which a brass bush has been made. It’s 15mm OD, and 10mm ID. The gearbox fits into the bush, providing the necessary support. Since these only spin at different speeds when the clutch is disengaged (i.e. no load), it’s hoped that the bush will be sufficient.

Next up will be engine mountings, since we have now sourced all the materials we need.

B

Is it poor internetiquette to put a keyword in the post that has nothing to do with the post? Probably. We have… a GEARBOX.
With a Rocam-based Locost, you have two choices for gearbox. The 5-speed Type 9 gearbox, or the 4-speed Type E gearbox. There are good arguments for both:

• Type 9 seems stronger
• Five gears vs. four…
• Type E is lighter
• Type E is much more common

Ultimately our decision was made when we found a very good deal for the 4-speed.

Some pointers for selecting your Type E (thanks Brad):

• Input shaft should be 1″ diameter, with 23 splines
• Input-shaft cover plate should have 4 bolts (not 3) connecting it to the gearbox body
• Gear lever should be the bolt-on type (three bolts). NOT the screw-in type.
• Check that you can get into all the gears (four forward, one reverse)

Like most things from a scrappy, it was in pristine, shiny condition when we fetched it. Other than being covered in filth, of course. And the aluminium tail casing was unbolted. And the main gearbox cover was off. And it was full of sand.

So out came the cleaning kit. It is easier to do once you’ve had some practice – paraffin painted everywhere to loosen the greasy gunk. Then Clean Green to wash it off. Repeat. Repeat. Repeat.
Once most of the sand was removed from the outside, it was time to tackle the inside. Paraffin was poured in, and the top cover re-installed. Then shake and leave for a day. This did a good job of softening and rinsing the inside. Pour it out, put in some fresh paraffin, and do it again. A bottle-brush was employed at some point just to loosen anything stubbornly sticking to the bottom.

The next stage was some cheap engine oil from Pick ‘n Pay. A flexible coupling (BIG word!) was made from hose-pipe and a 10mm drill bit, which allowed me to connect the electric drill to it.

Without the prop-shaft attached, oil poured from the tail-end, which served to flush out any stubborn grit. This will be repeated a few times just to make sure.

We also got our racing seats, and the seat runners were properly stripped of unnecessary layers. Along with the seats we got a fuel tank (seats and tank from Locost SA). The tank is excellent, with baffles inside to minimise sloshing. Photos of these bits soon.

Unfortunately it’s been almost 2 weeks since any work was done on the panelling. This starts again soon. We also have to finalise and check the brake lines quite soon.

For further inspiration, I went to the recent Zwartkops SuperTrax day. It was awesome to see all the other Lotus-type cars and get an idea of where we are headed.

Thanks for reading this far, please drop a comment, a criticism or just say hi.
B