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Fuel
New carb
Question: Could you advise me which carburettor would fit my 1993 1275cc Rover Mini Italian job? I believe an HIF38 would do, but would a HIF44 also fit?
Answer: Your original fitment carb will be an SU HS4. A straightforward replacement is the
simplest option. You could fi t an HIF38 but this would not be of any advantage; an HIF44 would provide a power increase but should ideally be fitted together with the larger (Cooper/MG Metro)-valved cylinder head and a suitable exhaust system.
Looking good! HIFs are the more dependable of the SU carbs for Mini
Electrics
Non-starter
Question: I am currently rebuilding my wife's Mini. Before it was parked up it ran okay. I have fitted a new battery but it will not start. The ignition light lights up but goes out when the starter is operated. I have cleaned the earth lead in the boot but this has not helped. The engine will tun over by hand. Do you have any suggestions?
Answer: This is a fairly common problem. Make sure the battery is fully charged and holding the charge. Disconnect the battery and clean up all of the battery terminals thoroughly and then do the same at the solenoid. Remove the two screws holding the solenoid to the inner wing, clean the rust off the inner wing around the mounting point and do the same with the solenoid. Refit the solenoid sing new screws. Reconnect the battery and the problem should be resolved. If not, check the starter connections and engine earth straps.
Engine
Which engine?
Question: I am restoring a 1964 Mini and do not know what engine is fitted to my car. I do not think it is a Mini engine because it has a mechanical fuel pump. The engine number is 99h962p168881. I would be very grateful if you can tell me the engine size and ear of manufacture.
Answer: Your 1964 Mini would originally have had an 848cc engine with an electric fuel pump mounted on the rear subframe. Our records do not identify your particular engine number exactly, however it is a 998cc engine. which I believe would have come from a late 1970s or more likely a 1980s Mini 1000.
Fuel
Poor running
Question: I have a 1998, 998cc Mini City that has no acceleration power. When I try to accelerate, there is sometimes the occasional loud pop or bang coming from the carburettor. I have been the problem could be a bent valve. Could you please tell me if there is any way of checking for this problem and if so how could I find which valve it is?
Answer: This is more likely to be an engine setup problem with mixture, timing or both. Check the inlet manifold, carburettor and vacuum advance for any air leaks. Ideally the engine should be setup on a rolling road.
Electrics
Indicator problems
Question: I have a 1983 Mini Mayfair. When I move the indicator stalk up or down, the indicators light up but don't flash. I have replaced the flasher unit under the dash, but the problem still persists. The hazards flash fine, but they use a seperate flasher unit. Someone suggested puting in an electronic flasher unit, which has a seperate earth connector, but I can't seem to find anything suitable for sale. Please advise!
Answer: Check all the wiring, in particular the earths, as a bad earth often causes the problem you describe. I don't think it's a good idea to fit a seperate flasher unit because I don't think that will solve the problem. I suggest that you take your car to your local garage and let them check it out. I don't think this is anything major and it shouldn't cost a fortune to correct, but I do think it needs professional attention.
Steering
No steering
Question: I have just bought my first Mini, a 1979 Mini 1000. I've only had it a week, but already I'm having problems with it. I was looking for a space in a car park when I made a turn, heard something break and suddenly there was no steering. The steering wheel turns inside the car but the wheels don't respond. Before this happened, I noticed that there was a loud clicking coming from the front of the wheel when I turned a corner.
Answer: First of all, check that the pinch bolt at the base of the steering column has not broken or come out and that the steering column has not become disconnected from the pinion on the rack. This can be done from inside the car. If all appears okay from the inside, it is likely that there is an internal problem with the rack. Whatever the cause, you will probably need a new rack to solve the problem.
Engine
Twin carbs
Question: I recently fitted a set of 1.5-inch SU twins to my 1275GT Clubman with a Maniflow LCB. But then when I went to start the car, I couldn't keep the revs down and noticed that the accelerator wasn't returning properly, which obviously wouldn't help. Is there an easy way to set the accelerator cable? I have managed to get some new return springs and although they are not the correct ones, they should do the job and make the throttle return quickly. Do you think these carbs will increase the engine performance by much?
Answer: The first thing to check is the routing of your throttle cable and that it is correctly linked to the carburettors. Make sure that you use the correct return springs and that they are correctly positioned. These are available from Burlen in Salisbury.
If the problem persists, look at the cable itself. Early cables had a tendency to stick, but the problem was cured by replacing the cable, as lubricating did not seem to work.
I think it's worth fitting these carbs and they should make for a very nice, responsive engine if they are properly set up, but I have to say that they will not bring about a massive increase in power.
Fuel
Twin tanks
Question: I would like to fit twin fuel tanks to my 1380cc Mini to increase its range. The only problem is that I haven't a clue where to start. Can you help?
Answer: Fitting twin tanks is actually very easy. The only hard part is cutting the hole on the driver's side for the additional filler pipe. The main difficulty here is that the left and right side of a Mini are not symmetrical and measuring accurately is made difficult because of this. The best way around the problem is to mark out the hole and cut the hole slightly smaller than needed, then fit the tank and line up and adjust the position of the hole by filing it out. The rest of the installation is a case of fitting the tank strap, etc, and plumbing into the original pipework. You will need to drain the original tank first.
Fuel
Question: I have just bought a 1974 Mini Pick-up. How do I find out if it has been adapted to run on unleaded petrol?
Answer: Converting a Mini to run on unleaded requires the cylinder head to be removed and fitted with hardened exhaust valve seat inserts to prevent damage caused by the higher running temperature when running on unleaded, while also countering the lack of protection that was provided by the lead content of the fuel. The only way to determine whether the engine has been modified is to remove the head and inspect it to see if inserts have been fitted. If you do not want to do this straight away use a lead replacement additive in the petrol until such time as you wish to overhaul the head.
Brakes
997 calliper
Question: I have managed to acquire a set of seven-inch diameter Mini disc brakes to fit on to my 1969 998cc Mini. I am trying to get hold of a replacement calliper as one of them has a broken bleed nipple (the nipple has been drilled out too far). Do you know of anywhere that I can get hold of a replacement calliper, or if not can I fit 7.5-inch callipers and discs to the seven-inch hubs?
Answer: Firstly, do not fit the seven-inch discs to your Mini. In the sixties and seventies some people actually converted Mini Coopers so equipped to drums to upgrade the brakes. You can fit Cooper S 7.5-inch discs to your Cooper hubs but you will need to fit the larger S-type CV joints and Cooper S drive flanges. It may be cheaper to start with a set of good second-hand 8.4-inch discs and shafts and modify those with S callipers and flanges or retain the 8.4 flanges and machine the 8.4 discs down to 7.5 inches.
Engine
Twin-carb set-up
Question: I have been told by someone who tuned Minis back in the Sixties that the best carb set-up for a Mini is a good twin carburettor one. I have a 1293cc Mini, which I am about to rebuild and further tune, and I have some secondhand twin 1½-inch SU carburettors from an MGB GT. Will these bolt straight on?
Trevor Smith
Answer: Twin carburettors are sometimes underrated by people nowadays.It's a shame because, although large single carbs work well on a rolling road and are favoured by insurance companies, when it comes to actually driving the car, a well set up pair of SUs is hard to beat. Fuel distribution is far superior, too, which is an important consideration. The twin 1½-inch SUs from the MGB GT can certainly be fitted to your Mini, provided you are going to a reasonably high level of tune (if not, use twin 1¼s) but the manifold, needles and float chamber adapters will need to be changed for the correct Mini items. All the conversion and reconditioning parts that you will need can be obtained from Burlen Fuel Systems on +44 (0)1722 412500.
Engine
Can I build a 1360cc engine?
Question: I have just acquired a 1275 engine, which I intend to rebuild and tune at the same time. I read some time back about someone building a 1360cc engine. Is it possible to build this using a standard crank or will I need to buy a specialist steel crank?
Andy Gibbons
Answer: There are two ways of obtaining a capacity of 1360cc, both of which use the standard 1275cc non-S crank. Firstly, the engine can be bored +0.040-inch and the stroke of the crank lengthened by offset-grinding the big end journals to Cooper S journal size. This reduces the journals in diameter from the 1300 size of 1¾-inch diameter to the S size of 1 5/8-inch, then offset lengthening the stroke by 1/8th of an inch. The second method is to bore the block to 73.5mm (which, with a standard stroke crank will result in 1380cc), but offset-grind the big end journals to S size but this time offset to reduce the stroke, thereby reducing the engine capacity back to 1360cc. Ready-modified cranks are available on an exchange basis from specialists such as MED (www.med-engineering.co.uk). The crank that is given in exchange must have standard size big ends and mains. A set of Cooper S or MG Midget con-rods will be also be required.
Interior
What does this switch do?
Question: My Mini Mayfair has a brake warning light switch on the dashboard. Could you tell me what this actually does, as no one that I have spoken to seems to know.
Stu Beckham
Answer: The brake warning light switch located on the switch panel of your Mini's dashboard is fitted to all dual-circuit-braked Minis and it warns
of failure of one of the circuits. The switch is there for you to test the circuit, which you should do on a regular basis. If the light is not illuminated when the brake pedal is depressed, but does come on when the switch is pressed, then the system is functioning correctly.
Bodywork
Fitting larger wheels
Question: I am intending to change the wheels on my 1977 Mini 1000, which is currently fitted with the standard skinny steels. I would like to upgrade these to 12-inch alloys, fitting 8.4-inch discs at the same time. Will I need to chop the wheel arches to gain clearance for the larger wheels?
Alan Pickering
Answer: As you are uprating your present drum brake set-up to 8.4-inch discs, you will be able to fit the 12-inch wheels with 145/70 or 165/60x12 tyres straight on at the front. At the rear, you will need to fit late-type Mini rear drums with built-in spacers and longer studs. You will not need to cut the arches to obtain clearance, unless you are intending to lower the car by an extreme amount or fit wheels wider than 5-inches.
Modifications
With or without the catalyst?
Question: I own a 1991 carburettor Rover Mini Cooper with a standard exhaust with a catalytic converter. I would like to fit a racier exhaust system and would like to know whether the car would fail the MoT on exhaust emissions if I remove the catalyst.
If I have to keep the catalyst, is there an exhaust system that I can I fit to improve gas flow and power output?
Tom Thompson
Answer: The Department of Transport vehicle testing office confirmed that, because it
was first used before 31 July 1992, your Mini Cooper does not need a catalyst in order to
pass its MoT. This is the case, regardless of the fact that it was fitted with one as
standard equipment. You can retain the cat and fit a system with an LCB to link up to the cat and an exhaust system to run from it, or you can ditch the cat and fit a link pipe in its place. If you keep the cat, you can refit it when you sell the car if you wish. Maniflow manufactures all necessary parts. Buy Maniflow manifolds and systems from most Mini specialists or see www.maniflow.co.uk
Engine
Can I fit a Sprite engine?
Question: I have just bought an old 1000cc Mini that is in good condition but which seems a bit slow compared to my old car, which was a Gilbern Invader. I have been offered a 1275cc engine from an MG Midget. Is it possible to fit this engine into my Mini and if so, what modifications would I need to carry out to the engine and to the car to make it fit?
Jerry Baldwin
Answer: The Mini and the Spridget were fitted with A-Series engines and, in the case of 1098cc and 1275cc engines, the capacities are the same. However, there are a number of differences between them. The most notable differences are in the crankshaft and block areas and they make it impossible to fit the Sprite engine to the Mini. The flywheel is fixed to the Spridget crank with bolts, whereas on the Mini it is a taper fit. TYou can use a transverse 1275 from a late-model BLMC 1300, or better still
a Metro, as these will go more or less straight in.
What is?
Knock on lock
Knock on full steering lock was one of the big things to check when buying a secondhand Mini in the Sixties and Seventies. It was essential to drive the car on full lock in both directions to listen and feel for knocking caused by worn outer CV joints. Minis had gained a bad name for this, along with rusting rear subframes. More than a few Minis were scrapped as a result. In all the Minis I have ever looked at to buy, I have only ever come across this once, and this was on a very rough Mini that was for sale for £5! CV joints today last a lot longer and replacing them is not feared as much as it was 30-odd years ago. It is still worth checking on Minis with high or unknown mileage. Make sure you know the replacement cost before you buy.
Fast Facts
New Mini classic?
The original Mini Mk1 became 'old hat' soon after the Mk2 Mini was introduced and the situation was amplified when the Mk3 came along a couple of years later. You needed that Mk2 grille and you did not want external door hinges when the Mk3 was introduced! People on a tight budget fitted Mk2 grilles to Mk1 Minis, usually without the bonnet lip, as this was complicated to fit to a Mk1 bonnet. Now that the Mk2 New Mini has appeared, what will become of the original cars? Will they become classics or will they be spurned in favour of the newer next-dress-size-up models?
Engine
Steady!
Question: The engine in my Mini is rocking about all over the place and bangs every time I pull away or take my foot off the accelerator. I have replaced the engine-steady bushes, but the new ones seem to have been knocked out after a few weeks. Should I fit upgraded bushes?
Tom Wetherell
Answer: Upgraded engine-steady bushes will certainly firm things up, but if standard bushes are wearing out in a few weeks, this suggests that there is another problem.
Replace the two main engine rubber mounts either side of the front subframe unless you know that they are new. It's difficult to check them visually. If your Mini has a lower engine-steady bar, check that the bar and its bracket are not broken. If there is any slack in the bushes, replace them. The same applies to the upper steady bar bushes. If your Mini is pre-January 1973, check the remote gear-change mounting located under the car near the handbrake, and fit a new one if necessary. Fit only top-quality bushes and mountings, as cheap ones will always wear out faster.
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