Is it just me or does everyone have troubles when replacing the carby on their mini?

Should I get a new one? or second hand rover ones should be ok?

Carby needles? Do i need a dyno tune to work out which one i need?




I just want my car to be driving nicely

How hard is it to get a carby working? Well depends on how much you know about them. If you don't know that much you might be better off getting it to someone that know's a bit about carby's and can tell you needles etc or ask on here. It all depends on the spec of your engine etc, and you need access to different needles.

The only sure way that you will know that your carby is perfectly set up is on a dyno. Some people can achieve good results without a dyno but it won't be spot on.

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"In two years time your car will be like a lady's clothes, out of date, my car will still be in fashion when I am dead" - Sir Alec speaking to Pininfarina

Any second hand carby should have a reconditioning kit put through it and have what ever worn parts it may have replaced. It you are not comfortable doing that by yourself then there are plenty of carby specialist that can do that for you. Just buy your kit from Midel in Sydney first so you dont pay extra for the kit.

Now on the needle issue - if you have a stock motor the you can pretty well go by the standard needle used on that carby for that motor. It will start and run and may be a touch rich or a touch lean for your specific motor and its stateof wear and tune. But who cares, it will run fine.

If you have a modified motor then it may well need at least a gas analyser and a set of needles to get close but a Dyno is better.

As a rule - minis are under carbied so the next size up will help, be older or newer style SU - not going anywhere near the Weber vs SU debate for this issue.

I'm sure it will get to that once alsminik see's this thread - well not really a debate - it might be a one word post again

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"In two years time your car will be like a lady's clothes, out of date, my car will still be in fashion when I am dead" - Sir Alec speaking to Pininfarina

I got 7 carbies... mainly 1-3/4" and they looked really nasty... dirty, gritty, yuck.
Had mine cleaned on the outside and then I threw it on my car. The needle was replaced but nothing else... runs fine.

The needle needs to match your motor... and then do your mixtures and you should be fine.

Why buy a new one if you dont need to?

Peter.

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Click here for the Turbo Conversion Thread!

ive just chucked carbies on car before that were sitting under the hioues
and they have worked fine, but i was lucky i guess, i agree with mike chuck
a kit through it and it should be fine.

is ur motor worked, if its not then gunsons colour tune will be good enuf for u
i would say.

I finally got my car sorted out today. Well I did yesterday, but today I need to get it to idle.

Anyways, I've spent a lot of money on professional help in this department which has come to not much more than a over rich car that blew smoke and did not much more than that. But It's fairly sorted now, no smoke and is a bit faster than it was when it did blow smoke so yeah. Alothugh the tuner did half the job correctly, carby was rebuilt correctly. Dyno was another story.

Oh yeah, as an aside the power is awesome.

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1964 Morris 850, 1330 Supercharged - 81.8hp atws.
1975 Leyland Mini S 1100S powered - Nice and reliable.
1977 Leyland Mini LS - Project LS-T

I always had a carby rebuild phobia, until recently. I sat down with a large plastic tray, and pulled appart the carbs in the tray. ALL the parts were there for me to see.

I bought an expensive rebuild kit (for twins) and put them back together piece by piece, replacing the bits that the kit supplied.

That phobia has gone now

Needle selection can be tricky. That's an expert job. One who has plenty on hand to try out.

At ~$20 each and with ~800 needles available, it's a lottery unless you know what you need.
I'll stick to Dellortos thanks, jetting is easy!

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

okay then what do you suggest i do.........

My original carby stuffing up - because, well No idea

So i bought a 2nd hand rover one.

Worked ok for a bit (not quite right) then recently just got worse.

When you look at the "butterfly" bit on the carby, i was told if there was wear and you could see daylight through the sides - it would affect the performance - and there is in the rover one but not my original one.


what do i do?>

Well very interesting topic here. Anyway I am planning to put my 998 auto carbie onto an injected 1275 auto? The carbie runs fine but spoke to a few people is better for me to get a carbie kit? What else do I need? a different needle? Also where can I purchase the carbie kit? Just saw someone said Midel in Sydney?

My carby kit came with replacement butterflies and shafts. Did your kit?

stef, put a kit through your old carby or the rover one. get the needle out of your old
one cos u noe thats the right one. put it back together and bobs ur uncle.

STEP 1
to tune it screw the mixture screw right up, then down 2 and a half turns, this is a good base starting point.

STEP 2
next there is a little button type thing on the side of the carby that u can press that will
lift the piston in the carby.

STEP 3
with the engine warmed up and running, press this button to lift the piston, if the engine revs rise slightly and the engine dies, its to lean! turn the mixture screw down in half turn increments

STEP 4
press the button again, if engine revs rise and stay high, its to rich, wind the mixture screw back up half a turn.

you are aiming to press the button so that the revs rise slightly, but then then they drop back down to normal fairly quickly!

(nb when i say press the button, you want to hold it up for a bit so u can listen to see what happens as the piston is held up.)

there may be other ways that people tune single SUs but this way has always worked very welll for me.

talk to me on MSN if u need any more help.

Gunson Colour Tune works for me.

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1964 Morris 850, 1330 Supercharged - 81.8hp atws.
1975 Leyland Mini S 1100S powered - Nice and reliable.
1977 Leyland Mini LS - Project LS-T

Chris
That method works fine in most cases. In most cases the needle will be plus or minus correct and lifting the the bell, listening for the rise or fall of the idle speed works.

The downfall is if you a swapping types of carby such as a HS4 for a HIF44 or even a HS2 for a HS4. Ignoring the fact that some have different design needles for the moment, the different carbies have very different flow characteristics and the needle from the original carby could have taper characterisitcs that may be way different.

Just swapping one carby for another similar carby is fine - its not going to be too far wrong. Swapping carbie types is not that simple.

I just wanted to make the point in case anyone was reading the various posts the wrong way.