1981 Mini City 1000

[The Marcos Graveyard]

How much advance would there be just by moving one tooth on the cam gear?

[ctwomey]

How much advance would there be just by moving one tooth on the cam gear?

There are 40 teeth on the camshaft gear, so that is 9 degrees per tooth. Woodruff keys are available from 0 - 9 degrees.

[ctwomey]

Gearbox finally finished and looking sweet too.

Once the engine is finished I am going to try and run it outside the car, that way I can do some checks and tuning plus check for oil leaks from the gearbox or engine.

Has anyone run an engine outside of the car before?

I still a few items to address first on the engine (distributor, carburetor, oil filter housing, inlet and exhaust manifolds and flywheel and clutch) plus I have a bunch of parts that I need to shot blast and paint.

Installed some old CV joints to enable the running outside of the car.

[The Marcos Graveyard]

Ronan had a stand for running engines on back in the day, frame to hold the engine and a panel with a few gauges to check oil pressure, water temp, rev counter that sort of thing

[ctwomey]

Finally got the 5 degrees offset woodruff key. Re-ran the timing with it installed and discovered I put it in the wrong way round. Anyway, changed it around again and now have the timing at 107 degrees as per the camshaft spec.

Oil pump and core plug installed at the end of the block. I use Loctite 638 bearing retainer liquid on the water and oil core plug edges.

Plenty to do over the coming weeks as I have almost all parts to completely assemble the engine and the gearbox.

I have been busy shot blasting, priming and spraying a lot of the old parts such as the timing chain cover, tappet covers, rocker cover, and radiator cowling plus a host of smaller parts. I used satin black as I want to keep it as close to the original factory look as possible. Always felt that gloss was too shiny. I didn't powder coat them or use a 2K paint for a number of reasons. In lockdown too much hassle to get all the powder coating done and the 2k paint isocyanates are too dangerous to use at home. I used 2 x coats of primer and 3 x coats of satin 1k chassis black.

I have also restored the old inertia starter motor and it looks really great. I also have deep cleaned the SU HS4. Will post pictures of before and after when they are finished.

[The Marcos Graveyard]

Love this, great work.

[ctwomey]

Finally got the gearbox and engine bolted together. The engine stand is a dream to work with.

Also bolted on the flywheel housing. I noticed the front mounting bracket is missing so I will have to source one and also slightly longer studs to support it's 5mm thickness.

Did some research and it appears that the Victor Reinz composite head gasket is the most reliable on the small bore engines.

Head all torqued up too. I have 3 x torque wrenches to work on engines. One for the 5-12NM, 12-60NM and this one for 40-210NM. Takes all the guessing out of assembly.

I was originally going to buy a lightweight flywheel but the more I read the more I realised it's a waste of money on this engine. So the old pre-verto is a bit rough so I am cleaning it up and then going to get the clutch surfaces remachined to take any grooves out of them and return them back to factory smooth.

[The Marcos Graveyard]

Is your oil pressure gauge union going to clear the feed pipe to the oil filter at that angle ?

[ctwomey]

Is your oil pressure gauge union going to clear the feed pipe to the oil filter at that angle ?

Never thought of that. I am planning on using a billet oil filter housing (to get rid of the dreaded bypass valve) and a braided stainless steel line to the filter housing so that might clear it. Otherwise I will have to adjust the oil pressure gauge union.

[ctwomey]

Getting around to restoring some of the ancillaries for the engine.

Starter motor heavily rusted on the outside

But after a strip down, clean, shot blasting and a few coats of satin black paint it has come out really well.

[ctwomey]

Carb has cleaned up pretty well.

Dismantled, cleaned, soda blasted and finally a low pressure glass bead blasting to get the shine back. Butterfly spindle needs replacing as it is worn which I will need to order but I have the standard service kit for the rest of the wearables.

[The Marcos Graveyard]

Great work again.

Maith an fear.

[ctwomey]

Pre verto flywheel has cleaned up well and both the clutch face and the internal tapper face are in excellent condition with no signs of fretting.

Unfortunately the clutch pressure plate is a mess and I suspect it was switched out at some point with the original because there is no way these both came off the same car. The machine shop recommended replacing it instead of trying to machine it, so will replace it with an EN8 steel one instead. It will save 1Kg in the overall mass of the flywheel assembly, nothing to drastic.

Hope everyone is keeping safe.

[ctwomey]

Finally new clutch back plate arrived. It's 1.22 Kg lighter than the stock one. It will be great to lose a little weight off the flywheel clutch setup without going for a light weight steel flywheel.

Took the engine and gearbox off the stand. Installed a new oil filter housing, braided hose and inserted the last two core plugs that I couldn't access while on the stand.

I also attached the oil pressure gauge and have been able to get a small bit of pressure just turning the engine over with a socket on the pully bolt.

Only things left to order are new dizzy, exhaust and inlet manifolds. Should be ready to attempt a start then.

[ctwomey]

Finally got the engine running this weekend. Used Calverst’s method for running in the camshaft and camshaft followers. Warmed it up first for 1 minute without water just to get the initial timing correct. This was followed by retightening of the cylinder head and adding water to the cooling system.

Afterwards I did 4 x 5mins runs with the engine at 2500rpm. Allowing cooling down and inspection after each run. Advance is around 26 degrees @2500 rpm. This is probably a bit too much but didn’t want to test full advance just yet to verify the max advance.

Anyway time to put the engine away and get cracking on the body shell. First job is to build a rotisserie this will help me hone my welding skills. Going to try and order all the necessary panels before end of year and before we run into customs issues with the UK.

I would post a video of the engine running at @2500 rpm but I think the forum doesn’t support it.

Stay safe everyone.

[Billy]

Keep it up. Great stuff.

[ctwomey]

Posted some videos up on YouTube

RC40 noise - https://youtu.be/e_ESQL6K0Gk
Walk Around at 2,500 rpm - https://youtu.be/VlZcRS_Mjbo
Timing Light - https://youtu.be/BaXvhtOHaLo

[ctwomey]

One of the concerns when running the engine was the oil pressure was very high > 100psi. I had changed to the Cooper S ball and spring for the oil pressure relief valve. I have now machined about 3mm off the length of the spring. Turning over the engine cold the pressure has dropped to a safer 75psi. Horror stories of blown oil plugs from the oil galleys and erratic idle made sure I got this sorted quickly.

[woody]

Some people think more oil pressure the better but as you say it can do a lot of damage . The real test is when the engine is good and hot . If you have driven a Sportspack with the oil temperature gauge you can see how much longer it takes to heat up the oil than the coolant.

[ctwomey]

Stripped down the rear subframe. The only issue I ran into was one bolt sheared off, so in the progress of removing what's left. The weld that holds the nut in place on the subframe has started to give way so I might need to weld in a new one or replace part of the steel plate.

The subframe isn't too bad, a lot of the rust is just on the surface, so until it gets shot-blasted won't know if it will need replacing.

Started to mock up the rotisserie that I am making

Lots of welding to do but progress is quick. Ran out of 25mm x 50mm HBS so might have to wait until after lockdown to get more.

A shout out to Hassets Nuts and Bolts in Limerick. Liam and Steve have been providing me with metric and imperial nuts and bolts for both the engine and for the rotisserie. They will deliver what they have within 24hrs. Super service. Just send them what you need and they will try and match up with their stock. Even managed to get some old BSF thread bolts for an old pillar drill I restored over the last couple of weeks.

Any idea where the best place is to buy 20 gauge sheet steel for making up patch panels?

[colinf1]

Looks like there was at least some paint left on the subframe. I've 2 broken bolts in mine so will be interesting to see how you go about sorting it.

Where the flexi pipe unions hard to get off? Still have one stuck that I haven't managed to get off yet.

Are you going to paint it or get it powder coated?

[ctwomey]

Hi Colin,

Are you going to paint it or get it powder coated?

Not too sure yet. Powder-coating will involve them (the powder coating company) shot blasting it and powdering it before I get a chance to repair or examine it. Could cost quite a lot to get done too. 2K is too dangerous to use at home because of the isocyanate. Thinking of looking at epoxy mastic 121 that has a hardener but doesn't use isocyanates. An A2P2 filter would suffice for this plus you could use it on all the other suspension parts as they get cleaned up. I have a small shot blasting cabinet that will help with the cleaning of those.

Where the flexi pipe unions hard to get off? Still have one stuck that I haven't managed to get off yet.

Mine are 40 years old so not reusing them. I cut the tube and used a deep socket and ring spanner to get them off. I wouldn't trust the solid brake pipes either. In fact, they twisted and tore very easily.

Looks like there was at least some paint left on the subframe. I've 2 broken bolts in mine so will be interesting to see how you go about sorting it.

I have drilled a small hole down the centre of the broken bolt. I will use a bigger and bigger drill bit until it just touches the threads and then I will use a special tool to remove the remaining bolt. I still think the nut is going to break off so I will need to repair that small section with a small patch panel. It looks like it is 16 gauge steel.

[ctwomey]

Finally got my welder setup this week. I installed a 16A socket into the garage. I was fortunate that I had a spare 20A MCB that was serving a single 13A socket that I replaced with a 16A one.

Got myself a decent 20L tank of 95% Arg / 5% CO2 also.

Welded some of the rotisserie together. Welds are ok and getting better slowly. Practice makes perfect and all that. Yes you buy a rotisserie but I felt by building one I would become a better welder. Steel is not that expensive.

[colinf1]

Welds look pretty neat! You should see my pigeon poo welding, and if it's not too it's a big hole where it's blown through!

Are you using plans for the roll over jig or just making it as you go?

[ctwomey]

Are you using plans for the roll over jig or just making it as you go?

No plans Colin, but have looked at lots of videos and pictures of similar jigs.

The one measurement that is a bit of a guess is the center of gravity for the shell. The closer you get to this the less effort and more stable the rotation is.

Additionally, you also need to know how far from the pivot point the base needs to be so in order to clear the roof when you do a complete rotation of the shell. By my calculations, 1 meter gives you about 100mm of clearance when the pivot point is near the front bonnet latch. Fingers crossed. I am sure someone with a jig can verify the same.