Author Topic: Mini Cometesse work  (Read 6186 times)

Big Al

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Mini Cometesse work
« on: November 26, 2015, 10:29:55 AM »
The incoming Mini Comtesse has been put to the garage to resolve some issues.

It has been unused for a few years but a quick service got it going. It was willing enough going up and down the lane, but continually seemed to be getting too hot, or stalling. Eventually the electrics began to draw a lot of current and driving in the dark become next to impossible. All a bit odd

So it was pretty clear there was a electrical drain somewhere. A check of the system revealed a pair of over spec halogen bulbs in the headlights. So that was draining the system, in use. Removing the blower wheel and casing from the Sachs 47cc unit allowed a view of the starter unit. I slid out the brushes to isolate the live circuit. Immediately I could see the problem. One of the stator coils was shorting, sending puffs of smoke out, each time the starter button was pressed.

So off with the Motoplat Spanish made unit - not the expected Bosch. This is held on by only three set screws. An unhappy arrangement. It was pretty clear someone had been here before. On one of the set screws the shrunk wrapped plastic insulation had become caught in the threads and had unscrewed itself leaving bare some 5mm of bare steel the other end. It was here the unit was shorting as the coils have only shellac and are hard against the set screws. A poor design.

I managed to reposition the insulation, but switched the set screws round as one was a much less tight fit, the bad one went there. The coil itself showed little damage and I added some insulation, tied on with cotton and doped with some shellac. Pigging difficult with my sausage fingers at the other end of a closed cylinder! My collection of tweezers and probs once again paid their dues.
The unit was put back together and we had integrity of circuits. However now the starter struggled to turn. Taking it off again it was clear that the commutator had been rubbing on part of the stator. Here some fiddling revealed that this unit has no way of locating it centrally that I could find then. With three set screws it is all to easy to be off centre. However despite that the commutator, presumably mounted on a taper, did not look like it was centred. A pencil held across showed a slight eccentric rotation. I am at a loss to understand how that has happened but only removal will eliminate the possibilities. Dirt on the taper, the wrong key in the keyway, or a bent crank or commutator! Experience has taught me not to discount some Herbert in here with a big hammer.

As a test of the rest of the car I put it back together. The play in the stator mount was such I could create enough room for the unit to work fine, but with the brushes moving a lot, sparking. The car ran up but we then ran into some fuelling dramas. This was an issue to resolve later, so that is where work stopped. I need to get the commutator off the crank to see if I can get it to fit and have the assembly central. I feel sure there should be a couple of dowels or a flange to place the stator firmly in the correct place. If not these later engines are not as good a quality as the earlier ones. Seems unlikely.

For the rest of the car there have been some tidying of wire ends, earthing and such. The speedo does not work the Huret speedo. Not looked at that yet. This version has never had waist lights, nor pedal power. Sadly its lost the original rear lights, but the replacements use the same holes, I think. Given supply, an easy reversion to original. Less certain about the headlights. Not sure what was the original fitment, maybe only the bulbs were changed. Brilliantly the wiper motor retains its hand switch on the end, but is wired to a remote switch too. So it can be turned off twice!.

The cycleparts, brakes and steering show minimal wear and overall its in very good condition, no damage, green interior in perfect order. I had to rebuild the locking double door lock. Who ever put it together last time had assembled it to work backwards, thus the tab that locks the bezel had been able to fall sideways slightly and no longer was the cam on the end of the lock able to rotate it fully. Easy mistake to make and I bet others have done the same. Its a weak handle design on that door and I can imagine it being a nuisance. The ordinary door only locks from the inside. I think both are borrowed from Citroen.

Once I have resolved the car back to working, it will be available to a buyer. It has its 1975 registration already, so £17 or tax free next year, as its a 3 wheeled Moped class. Perfect for under-age driving too. Light enough to restrict the speed and use as a pavement mobility car. Goes very well. with more to come I think. Not sure tuning is plum. The auto box changes beautifully and holds gear on demand. Not seen a better one and this one should sell on the button, ready to go.
Messerschmitt set, Goggo Darts, Heinkel 175, Fiat Jolly, Autobianchi, Fairthorpe Electron Minor, Borgward, Isuzu Trooper
Citroen BX 17TZD & GTI 16v
Held - MG Magnette ZB & 4/44
For sale - Vellam Isetta, Bamby, AC Type 70, Velorex, Church Pod, Reliant Mk5, KR200,  Saab 96, Bellemy Trials, Citroen BXs

steven mandell

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Re: Mini Cometesse work
« Reply #1 on: November 27, 2015, 08:34:40 AM »
High order trouble shooting Al.
All those years of experience and clear thinking paying of here
It will be interesting to discover the source of your commutators eccentricity.  Likely more simple than your own.
Was yours built in 1975?  I trust it is the three wheeler without the extra front training wheels.  I have one of these on the way that has lost its front bonnet.  Are they the same as the ones used on my early (1973) 5 wheel version?   If they are, I at least have an original to pull a mold from.

Let me know if you need referential info from my early car.  Cleaning the tank is easy enough, as it does out with loosening of the straps.  Cleaning the gas valve helped one of my fuel supply issues.  But whilst rebuiling mine's carb I noticed that the float was inexplicably partially melted in appearance.   [Anyone know where i can find a replacement float?].  This brought its centralizing spear out of centricity.   I centered this locating spear by very careful bending and polished the shaft and ends to allow both better vertical float motion and sealing off of gas flow when the float chamber  fills.   But the arrangement still requires me to perform a very siily looking but effective ritual each time that i start it. I start by sealing my mouth firmly over the gas cap affixing protruberance on the gas tank.   I then blow mightily into the tank whilst pushing down on the external end of the float tickler.  Usually 3 times is enough to see some gas over flow.  It then starts instantly with just the slightest of choke.  Good entertainment for the masses.

My windshield wiper is the motor less hand operated one- so more reliable and less electrical drain as well as higher laugh factor.
« Last Edit: November 27, 2015, 08:38:23 AM by steven mandell »

Big Al

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Re: Mini Cometesse work
« Reply #2 on: November 27, 2015, 11:24:29 AM »
Looking for info on the dynostart I found this, presumably on the auto clutch. Needs translation prog but just adds to the excitement.

http://www.classicmotor.se/artiklar/experten/20141229/fel-olja-i-sachs-saxonette

http://www.classicmotor.se/artiklar/experten/20101104/saxonette-automatic-vaxlar-inte

I also want to check which way round my carb needle is - might be causing my fuelling prob. My float is brass. More on that later.
« Last Edit: November 27, 2015, 11:40:08 AM by Big Al »
Messerschmitt set, Goggo Darts, Heinkel 175, Fiat Jolly, Autobianchi, Fairthorpe Electron Minor, Borgward, Isuzu Trooper
Citroen BX 17TZD & GTI 16v
Held - MG Magnette ZB & 4/44
For sale - Vellam Isetta, Bamby, AC Type 70, Velorex, Church Pod, Reliant Mk5, KR200,  Saab 96, Bellemy Trials, Citroen BXs

Big Al

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Re: Mini Comtesse work
« Reply #3 on: November 29, 2015, 09:19:38 AM »
Well part of yesterday was spent fiddling with the Sachs engine, in between despatching the last of the Invacars in long storage here to Simon, and picking out the 'best' Villiers engine for a buyer. I sincerely hope it is, but its hard to pick out of three very similar lumps each with slightly differing issues visible. I think he chose right as oil came out of the one taken, suggesting clean internals.

The fiddle to set up a test on the commutator was worth it. My dial gauge has got busted in the move, a spindle bearing has come out and vanished. So I did it electronically. That is run a loop of wire through a multimeter and made a prob from thick household mains cable. This was then set to run on the denuded snub end where the cam lives. Several runs were needed to find any areas that the contact broke. It was found to be in one continuing area over the rest of the rotation, meaning the Commutator is slightly miss aligned. I do not have the extracting tool to hand.
The base plate of the starter was behind the stator. It to was on three fasteners and turned out to sit in the machined position of where a magneto would sit on a kicker engine as a conversion plate. With the screws loose this rotated about the set screws easily. But it also had a small amount of up/down play. So how do you get that bang in the centre? I am attempting to do this with filler gauges between the outer case and the converter plate to get equal values for the three out of four directions I can measure. Such niceties might not be needed if the commutator was true but both being a little out seems to be enough to create a problem. In truth it is poor engineering accuracy, and design. Is the Bosch unit the same?

I have located a source of the correct rear lights, this being a later car. Some ruminating on the age suggests the 1982 issued number might well be earlier, at 1975, that the vehicle actually was made. Buy using the French homologation date for the 'MK2' MINI COMTESSE IT MIGHT BE THAT THIS IS SOMETHING LIKE A 1978 CAR, IN REALITY. A COLLECTION OF SOME CHASSIS NUMBERS ASSOCIATED WITH KNOWN MANUFACTURED/SUPPLIED DATES WOULD SERVE TO INDICATE A RECOGNISABLE PATTERN OF DATING for these cars. This in itself would make gaining a V5 easier as DVLA can be given a year in which the car was made with the confidence of back up info. This car having a V5, the date is somewhat academic, but I like to know such things to get the right bits to repair it with.

On which topic. I would like to see if I can buy a pair of headlights. I am certain mine are not correct. I would expect Cibie, CAV or some such. They habitually have yellow bulbs, or reflectors, for that French character. So can anyone tell me what units these should be.

I was looking for clues and came open Steve being interviewed and filmed arriving for the Lemon award at Monterey? The car was looking and sounding good so clearly the unusual design baffled into placement as a Lemon.

Found a load of other stuff I did not know about too. Stuart was here helping so I might have set him off on a hunt for more oddities. He was able to negotiate DVLA's systems and we pretty much proved that my car is the ex Bob Cotton car, possibly the first that came into the country. Its famously pictured being push started (not easy on an automatic) by Micro Maniacs during a Weston Park? Rally.  Did it complete the slalom thus, I forget. Does this suggest Alan Forster as pilot? So its probably on the Register.
« Last Edit: November 30, 2015, 08:54:23 AM by Big Al »
Messerschmitt set, Goggo Darts, Heinkel 175, Fiat Jolly, Autobianchi, Fairthorpe Electron Minor, Borgward, Isuzu Trooper
Citroen BX 17TZD & GTI 16v
Held - MG Magnette ZB & 4/44
For sale - Vellam Isetta, Bamby, AC Type 70, Velorex, Church Pod, Reliant Mk5, KR200,  Saab 96, Bellemy Trials, Citroen BXs

Big Al

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Re: Mini Cometesse work
« Reply #4 on: January 03, 2016, 10:44:52 AM »
Various diversions, but back to this car. I hand no puller to get the commutator off the crank. The system is much like an BMW Isetta or Goggomobil where there are, in this case 10mm threads in the commutator and 6mm threads in the crank. Thus a tool can be placed in the larger thread to bare on the end of the crank and get the unit off.  THe smaller thread carrying a long bolt to hold the assembly to the crank in use. (BMW/Goggo, I think it is 14mm and 10mm)

Without a puller its always a uncomfy moment to put a made up shaft of steel in and nip it up with a handy bolt. If it failed to work, is soft steel or some other issue unseen is lurking, you can get into frustrating problems, even to the point of a scrap crank. I put a little tension on, but it just did not feel right. So back off and out. Yet even now the shaft I put in would not come back out of the hole. So we drilled a hole in the end and put a screw into it. Nope, full movement sideways but it would not withdraw. So it must have belled out, though it looked OK. Swear words.

I now had an idea I should have had first. Tip the car over and fill the hole in the dynostart up with oil from a syringe. Took three goes to get enough air out of the volume inside. Since you cannot compress a liquid and  it pushes equally on all surfaces it does not force the stuckl rod stuck any further and should pop the unit off its taper. It did. One up to brain cells.

Now we could see the rod I had put in. It was bonded to some other metal that was itself stuck in the crank threads. Gingerly I got a pair of pliers to unscrew this failed thing. fearing it would shear off at the beginning of the thread leaving more drilling to be done. Luckily it all unscrewed leaving some pretty damaged threads. A look at the taper and key told the story. I was right. Someone had been in there and the key was displaced high to the front by swarf underneath it. The sort of black oil stain you get on these joints, at the clench edge, showed an area that had been a gap in line with the keyway. Evidence it was not on square. It was just being held off square by the swarf, but the taper was good enough to grip none the less. The Afternoon of work ended with a search for my taps so I could clean up the 6mm crank thread. They proved more elusive than some ale and cheese. But I feel confident that reassembly will provide a centre set dynostarter and hopefully, therefore a free and fully functional engine.

The remaining mystery is how the fastening bolt was doing anything and remained in place. The end is damaged so it may have been screwed into the remains I destroyed with my little shaft. I shall have to measure it. maybe its to short for the real task.
Messerschmitt set, Goggo Darts, Heinkel 175, Fiat Jolly, Autobianchi, Fairthorpe Electron Minor, Borgward, Isuzu Trooper
Citroen BX 17TZD & GTI 16v
Held - MG Magnette ZB & 4/44
For sale - Vellam Isetta, Bamby, AC Type 70, Velorex, Church Pod, Reliant Mk5, KR200,  Saab 96, Bellemy Trials, Citroen BXs

steven mandell

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Re: Mini Cometesse work
« Reply #5 on: January 03, 2016, 05:57:09 PM »
Fascinating tale of brains over brawn.
If I am conceiving properly- would a shorter made up threaded rod section been able to avoid the belling?
Have you ever had any luck with a poor man's hardening of heating up your made up tool with a torch till the right color glow achieved, and then suddenly dunking in an oil bath?
If so, could that have helped?
So the winning ticket was  to compress the oil in the chamber created behind your made up threaded shaft insert tool, by screwing in the center bolt?

Hopefully a longer highly hardened bolt and perhaps a flat bottom tap chasing out your crank threads to a deeper depth will save your day now.
I wouldn't have dared do anything but research on the internet and other sources to try to find someone selling the needed tool, and waited the requisite period to receive it in the mail.
Good thing your brains are as big as your bravado!

I will be working on my newly received Solyto, and Super today.
My day yesterday was similarly frustrating as a well meaning, but overly eager volunteer helper hit the gas pedal whilst I had the top to the air piston of the Solyto's Gutner RN 17 carb unscrewed.  A "ping" was heard and the piston slide return spring no longer see , as the gas pedal plunge had caused the molded lug at the end of the throttle cable to escape from its angled bore in the no longer angle constrained(it was out of its bore) throttle piston.   
To make matters worse, the car was outside at the time.  After an hour thoroughly visually searching the engine compartment and a radius of about 30 feet from the epi center, and literally picking up the front end of the car a couple of feet and dropping it to shake anything loose out- nothing but swear words.  Metal detector faired no better. 
About this time my underly cautious assistant decided to over come what was noted to be a kink of resistance in the steering, by twisting the wheel back and forth harder each pass.  Before I could get him to stop- it released.  I then noted an extension spring on the floor of the INTERIOR of the car.
Knowing that the missing spring was a compression spring, I dismissed it as an extra problem in some as yet unseen chain tensioning system.  However, after discovering a thoroughly mangled spring rung remanent under the seat an hour later, I decided to have a closer look at the found extension spring.  It had the obligatory hook on one end, but ended with a flattened coil on the other end. 

After realizing that there could be no use for  a spring that was configured for compression on one end and extension at the other, I realized that my assistants rowing at the wheel must have caused the modification toi the compression spring, and spit out a rung and a half worth of remnants in the process! So the spring had shot the improbable path through the small opening in the firewall and got caught in the steering chain, in an area that is well hidden from prying eyes.    I have managed to reconfigure the hairpin twist in this hardened throttle piston spring into a useful rung, but would have too short an overall length if I were to create a flattened rung in the end.  So there is inevitably some side thrust on the piston due to the spring's new end configuration causing it to lean away from its landing.  Three hours in hardware stores looking at about a thousand springs to no avail.

Anyone got a clue where the right one could be found?
 Next the bung at the end of the throttle cable popped off, and then escaped from an unnoticed small hole a plastic jar that I had placed it in for safe keeping somewhere  between my spring shopping travels.  Another hour of scouring floors and parking lots for the tiny piece before I threw in the towel on finding and re soldering it.  The local bicycle shop provided me a thinner but strong stainless steel cable and housing, but with a bigger bung that I hope to grind to fit by spinning the cable by hand against my sanding disk.

Now the Comtesse Super.  Its entire fuel delivery system is only about 14" long yet had 6 leaks.  After trying to rebuild the petcock with every metric sized O ring that I could find at the parts store, I spent a few hours on the internet and phone, and replaced the whole valve and a low resistance inline filter for just $20.  Hopefully it will become a runner without the unnecessary  downward spiraling of disasters of the Solyto, as I will be working alone this time.   
« Last Edit: January 03, 2016, 06:08:38 PM by steven mandell »

Big Al

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Re: Mini Cometesse work
« Reply #6 on: January 04, 2016, 09:25:05 AM »
Fascinating tale of brains over brawn.
If I am conceiving properly- would a shorter made up threaded rod section been able to avoid the belling?
Have you ever had any luck with a poor man's hardening of heating up your made up tool with a torch till the right color glow achieved, and then suddenly dunking in an oil bath?
If so, could that have helped?
So the winning ticket was  to compress the oil in the chamber created behind your made up threaded shaft insert tool, by screwing in the center bolt?

Hopefully a longer highly hardened bolt and perhaps a flat bottom tap chasing out your crank threads to a deeper depth will save your day now.
I wouldn't have dared do anything but research on the internet and other sources to try to find someone selling the needed tool, and waited the requisite period to receive it in the mail.


The tool for removal is a 10 mm threaded bolt with a machined down prob on the end that I geuss must be 8mm. THe idea being it winds into the commutator and the prob lodges against the shoulder of the crank, not the threads. Then it is turned and given a smart tap to break the tension in the taper. I attempted to make a two part version. Where I failed is because the remains of something else where left in side the assembly, presumably after a failed attempt to remove the commutator with some spacer of soft material. I think this had been drilled into and a bolt wound in to effect the look of a correct assembly. In fact it was a mess.

The repair will be to recover the crank's 6 mm thread and find a new bolt to fasten the commutator in place. Such is the fit of the clean taper just hand fitting it means its hard to shift. We are not looking at something wound to a high lb ft. Hopefully this will remove the eccentric movement and the dynostart can be set up to work without extra friction, nor deviant points response. If so then the rest of the engine is very willing to give good power.

i still need to find out what the correct brand of headlight should be. I have found the rear light units new for this particular model. Those items done the car really is pretty much bung perfect and will want a new owner who can actually use it.


The ability of parts to get to what seems impossible places is an ever gnoring source of irritation. It is also exacerbated by the 'helpful', who seem never to fully appreciate that fixing cars is a logical progression, not playing around with random assemblies unbidden. Unless they can be kept busy, they are often more of a distraction. Yet those same 'helpers' never have the patience to clean up things or do repetitive tasks. The graft of self maintenance. Real helpers tend to fit in without having to be told what to do as they understand what is going on. The 'helper' will then expect your reciprocation on his car, where you fix it, because he actually does not know how too, despite having better tools that you have got. Generally the deal with 'helpers' is not worth it.
For instance, a 'helper' managed to nearly loose the woodruff key from the Comtesse Commutator by sprawling over the car, dislodging it from its resting place. All the nuts and bolts got moved, not to the same place. Then he blew a fuse on the TT mucking about with switches, while I was circuit testing. A set of test that, of course, told me nothing, since I was not aware switches had been changed. And so it goes on. Because they endlessly fidget these folk never watch and learn from what you are doing. Which is the most annoying thing of all. You know your going to get asked the same question in some future situation.

As to resolving the spring issue. Hard to say without seeing the assembly. But there seems to have been a problem with the throttle return, before you intervened in the assembly, from what I picked up in my other messages I have yet to catch up with. That the cable end should fail, or pull through, is a fair amount of pressure.  I can only admire your bravado of taking on cars not fully running, and/or unseen, as projects bought in. I always assume stuff has been mullered until proven otherwise as I am conv9inced that 95% of people these days cannot fix a thing properly. Without the benefit of knowing what should be there it is thus very hard to return some things to functionality. Again the TT is a perfect example. Who ever built it never bothered to do a wiring diagram. The wires are inconsistent colours on a run, they are neither Messeschmitt, nor CN250. Some wiring is yards to long, others just reach. Its a complete nightmare to fix as most of the spade connectors are cheap and loose. When they fall off its very hard to know where they came from. Its a botch from one end to the other. I have given up. The car needs rebuilding and if that is the case it wants Schmitt front axles on it so it actually works as a car, rather than a random directional coin ride.
Messerschmitt set, Goggo Darts, Heinkel 175, Fiat Jolly, Autobianchi, Fairthorpe Electron Minor, Borgward, Isuzu Trooper
Citroen BX 17TZD & GTI 16v
Held - MG Magnette ZB & 4/44
For sale - Vellam Isetta, Bamby, AC Type 70, Velorex, Church Pod, Reliant Mk5, KR200,  Saab 96, Bellemy Trials, Citroen BXs

steven mandell

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Re: Mini Cometesse work
« Reply #7 on: January 04, 2016, 11:37:39 AM »
Picture of Gurtner carb piston spring post having the Solyto chain drive steering mechanism chewing off a rung and a half, and my carefully reconfiguring the thus modified faux extension spring attachment loop into a useful rung. So overall length and resistance about the same now, but a little sideways thrust created by now unlevel perch.
My high idle speed was more likely caused by the carb's air piston's vertical groove not quite matching the clocking of the screw tip guide installed in the side of the piston's cylinder wall.
The popping off of the end of cable bung was due to my correcting the path of the throttle cable through the firewall, and then turning the engine and front wheel assembly to full left lock.  Even my new cable and housing that I installed today cannot accomodate this action, as it turns out that the "original" beat up cable housing, was probably just a beat up non original piece, that became thus endowed by virtue of its improper routing causing it to get beaten by a tie rod in severe left hand turns.  I unwittingly copied its too short cable housing length that was based on its improper routing, so wasted much time on precisely getting the bung end piece to a perfect stab fit into the top of the air piston's receiving bore.  I will have to start over again with a new longer cable and housing after a short sanity break.

What "TT" are you referring to?
I presume its not an NSU, or Audi.
Am I correct in presuming the CN 250 to be its Honda produced powerplant?
« Last Edit: January 04, 2016, 11:44:00 AM by steven mandell »

Big Al

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Re: Mini Cometesse work
« Reply #8 on: January 04, 2016, 01:35:16 PM »
Tri Tech. Normally I am breaking them up after a crash or fire. This one has not worked long enough to have one yet.
Messerschmitt set, Goggo Darts, Heinkel 175, Fiat Jolly, Autobianchi, Fairthorpe Electron Minor, Borgward, Isuzu Trooper
Citroen BX 17TZD & GTI 16v
Held - MG Magnette ZB & 4/44
For sale - Vellam Isetta, Bamby, AC Type 70, Velorex, Church Pod, Reliant Mk5, KR200,  Saab 96, Bellemy Trials, Citroen BXs

Big Al

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Re: Mini Cometesse work
« Reply #9 on: January 19, 2016, 05:06:19 PM »
Finally recovering from multiple illness after Christmas. Seems Vitamin supplements helped a lot. All that dull weather, no D3

So finally got to strip the second rebuilt Sachs 200 engine. Nice unit with steel conrod serviced crank on 66mm, second, new oversize piston. An expensive job these days. So if my client has sorted himself elsewhere that can go back on the shelf as stock. The other just needs a new piston and a better head cleaned up to be a very good unit too. Piston is fine for a spare engine, but not in a unit to sell on.

So the other job half finished was to get the Sachs in the Mini Comtesse back together. This needed a 6 mm tap, which I have found. I do not know if the damaged thread pre existed my efforts or if I have added to them. Certainly there is older damage to the face of the crank. That has been dressed up. All is ready to attempt to clean the unit out. But I decided to put off lying on the floor till tomorrow's daylight and an an old dovet to lie on.

Instead I scrapped two poor black boxes for parts. A time consumming activity as some of the rusted fasteners are difficult to remove. Both these are ex IC. But there is call for the manual switch gear now. Folk on a budget can use them on Villiers and such. a £5 answer to a Schmitt priced answer. Adds to my two large boxes of used coils. Really out to take these to a jumble as ideal spares for those touring, or on a budget.

Great to be back doing stuff.
Messerschmitt set, Goggo Darts, Heinkel 175, Fiat Jolly, Autobianchi, Fairthorpe Electron Minor, Borgward, Isuzu Trooper
Citroen BX 17TZD & GTI 16v
Held - MG Magnette ZB & 4/44
For sale - Vellam Isetta, Bamby, AC Type 70, Velorex, Church Pod, Reliant Mk5, KR200,  Saab 96, Bellemy Trials, Citroen BXs

steven mandell

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Re: Mini Cometesse work
« Reply #10 on: January 20, 2016, 01:16:01 PM »
Great to have you back online Al. :)
Just got my hoodless, seat bottomless Comtesse model 770 running well last evening after installing new and properly sized fuel line and filter, and fuel tap, and carefully rebuilding the non stock carb that wasn't allowing any gas through the truly tiny idle circuit orofices.
Had to refine a strip of polyethylene into an adaptor collar for compression mounting it onto the engine's protruding intake tube so that it wouldn't slip off or leak air into the intake charge.

Can't wait to take it out for a run today to see how she goes.
Engine started immediately, ran quietly and did not fill the barn with smoke after a full 5 minute indoor run.

Wondering if there is any reasonable fix for the curious mismatch that has some how gotten the choke to activate only when the dashboard knob is pushed fully in.
A bit awkward and anti intuitive to have the knob sticking out away from the dash when fully warmed up.
Or do I just add this to its already impressive list of needlessly distinguishing oddities?  Can't say that such a trait would betray its overall appearance for that matter.

Big Al

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Re: Mini Cometesse work
« Reply #11 on: January 23, 2016, 08:44:12 AM »
The joys of modified machines Steve. Choke sounds odd. But then some just have a strangler, and why not if it works as its simple. At least these issues are exchangeable if truly needed.

Here I have spent several hours salvaging the Sachs Crank on the Mini Comtesse. It has been in the hands of a very heavy handed person. First task was to clean up the thread of the crank so that the commutator retaining bolt, replaced from one of my amazing bit boxes. Same spec! Must have come from one of the clearances or a Mannheim box of crap deals. Just shows the boxes of old fasteners are worth keeping. Each gem getting you out of a jam is worth a wedge of dosh saved in getting stuck. I would say that the old bolt had been modified to go in. It probably did little but stay put. In the end I had to run a drill in to clear the hole back to the threads. Then create a frame to hold the crank and hold the tap at right angles so that I could then find the start of the thread and apply pressure to start the cut of the ingressed softer metal from whatever had been used as a distance piece in the previous attempt to pull the unit off. A task I could not rush, and I took out a bit at a time, it getting easier as I gained good thread.

The new bolt offered, it went in with no interruption on the second attempt and having passed the first few poor threads was biting well. However thoughts of assembly stalled as on offering the commutator up onto the taper I found it was wobbling. Indeed in the same plain as it was leaning previously. I removed the woodruff key think it was indeed the wrong one. Though it appeared to have swarf under it when dismantled holding it just proud. The mounted commutator still wobbled. I have not the tooling to true a taper. Thinking back to what we have I formed a theory.

Way back this engine had suffered a dynostart fault, or had been uprated to electric start. This would explain the Spanish dynostart? Who ever fitted it did not really know what they were doing. INstead of restoring the crank thread after botching the extraction, they adapted what was there and fitted the commutator by use of a mallet on the end to shock it onto the taper. I do not know how soft the steel of the crank is. Not very I would have thought. But how did he fit the woodruff key if it was not home. Ah ha! A check on the woodruff keyway slot relieved the problem. the edges were slightly raised. Chummy had hammered the key way in. We had a job to get it out. So it is the wrong woodruff key now, even if it was not at the start! The woodruff key slot has been dressed with a fine file and the commutator is now a firm fit without a key. Now to find a suitable key to use. I might have to file one down. REmember a keyway is a location device, not the item that holds the part in position, the interferance fit of the accurately matched tapers does that when they a driven together.

Such a small mistake, creating a long job, requiring great patience. But will the result yet provide a correct running engine? Should find out this weekend.

Meanwhile one Sachs engine is complete and the other awaits a new piston to be found out of my piston box, along with a better head and unmodified trumpet casing out of the stock at the shed. Then I can look at my own tuned unit for the St Helena car.
Messerschmitt set, Goggo Darts, Heinkel 175, Fiat Jolly, Autobianchi, Fairthorpe Electron Minor, Borgward, Isuzu Trooper
Citroen BX 17TZD & GTI 16v
Held - MG Magnette ZB & 4/44
For sale - Vellam Isetta, Bamby, AC Type 70, Velorex, Church Pod, Reliant Mk5, KR200,  Saab 96, Bellemy Trials, Citroen BXs

steven mandell

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Re: Mini Cometesse work
« Reply #12 on: January 23, 2016, 12:44:41 PM »
I didn't get why your new threads allowed your new found bolt to wobble.
Was there not enough meat for them to be cut into?
Did you redrill the crank hole a little deeper and end up using a bottoming tap?
Ditto the original woodruff  key now being incorrectly sized.
In which dimension did the previous gnasher's beating resize its slot?
If it is an oversized hardened key that you need to dress down, a filing of its surface seems doomed due to a lack of bite.  Perhaps a grind on your smooth cement floor, possibly aided by Emery paper and oil on a truly flat surface for the later stages will better get the job done.

Chris Thomas

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Re: Mini Cometesse work
« Reply #13 on: January 23, 2016, 05:54:25 PM »
Steven M and Big Al: A match made in Heaven.

Chris Thomas

steven mandell

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Re: Mini Cometesse work
« Reply #14 on: January 23, 2016, 06:21:17 PM »
Steven M and Big Al: A match made in Heaven.

Chris Thomas
A high compliment for me if we are to be considered equals.
However despite our having similar styles of communicating technical issues, I would consider Al to be unequaled in his near photographic memory and encyclopedic like knowledge of micro car engineering issues, as well as out of the box thinking.
Did you catch his recent post where he utilized hydraulic pressure generated by his turning in a bolt in a threaded chamber that he filled with oil?
 More than a bit of unbridled genius even if he does say so himself.

Al has amazed me in these ways dozens of times over the last few years when I have privately consulted with him.
Even my last post here is more of me questioning what he already described, rather than me making a useful suggestion, as I am sure that he is already well aware of the engineering principals/ techniques of which I speak.

Never the less, compliment graciously accepted.
« Last Edit: January 23, 2016, 06:23:40 PM by steven mandell »