Howdy all, I Have a problem with my mini. It's a 1275 with twin SU's. The problem is that when the car is being driven it surges as soon as it gets over about 2500rpm. It sounds and feels like the car is in the wrong gear. I have re-tuned the carbs and that didn't seem to do anything. The engine revs fine when not in gear. Any help is much appreciated.

ok,,,may be a problem with your distributor vac advance mech

have you got vac advance type dizzy fitted???

often the dizzy base plate wears & wobbles around like a dik in a shirt sleave & as the vac advance works it will wobble/cock the plate & open the points up more, then because the timing change occurs as the points open the vac drops & closes the points, but as the points close again the vac increases again, so the pull on the plate opens the points again, & so on & so on, surge surge surge.

catch 22 type thing...try disconnecting the vac advance (if you have one) & drive him magain & see if it still happens

cheers & let us know what you find

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

Cheers mate, I do have a vac advance dizzy, I will give disconnect it and give it a go tomorrow and then post again tomorrow night. Hopefully that will solve the problem. Thanks again

disconnected the vac advance lead from the dizzy, went to start it up... Now it wont start! I put the lead back on and tried again, still nothing. The exhaust is totally screwed, it leaks from the lcb where the two pipes go into the 'y' piece, would this be the reason it wont start or is it something ignition related?

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Howard: "You don't need a pen to be a writer Vince"
Vince: "I think you do"

HAHAHA Dixon Bainbridge! I love The Mighty Boosh!! That was the funniest show out! Pity it's not on any more. Sorry bout the OT post.

No worries chief, any comment of The Mighty Boosh is most welcome.

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Howard: "You don't need a pen to be a writer Vince"
Vince: "I think you do"

You guys and girls (incl myself...lol)live in a time warp. Love the image Dix ...what a hoot.

With the question at hand, do as Matt says.

The leak may be contributing to the no starting but there is something else there me thinks.

If it is surging also(and this is a long shot tooo), might be the clutch letting go when the revs get to 2500rpm??? I say this as I was on my way to a Kangaroos match last year and the car was slipping at 2000rpm...was the original clutch giving up the ghost(mind you it had 180-odd thousand kays on it)

Not doom and gloom and it is almost always a very simple thing99 percent of the time. Start with pulling all the plugs and cleaning them off with a wire brush(if there is a leak they could be heavily carbonised). Clean the dizzy contacts while you are doing the internals as well as the rotor button(incidently, that is my immobiliser now...pull the dizzy rotor...lmao!!)

Good luck at getting that Y-piece off too - that is my most hated job!!!

Hooroo

Rob Forsyth
Miniot!!

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Rob Forsyth
Miniot!!

thanks for that, i did take all the plugs out and they were all black with soot, does this mean it was running too rich? I'll give the distributor a once over too.

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Howard: "You don't need a pen to be a writer Vince"
Vince: "I think you do"

Maybe - but could be a combination of all things combined. The leaky flange will have contributed to it and if the soot gets too thick - it stops sparking. A quick clean with a brush should get you going again. With the SU - turn the jet nut UP!!! 3 flats, drive and check - if no longer black - wind down 1 and drive and check, so on and so on.

Get the exhaust fixed though - cant have you crashing the mini from CO asphyxia...

Hooroo

Rob Forsyth
Miniot!!

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Rob Forsyth
Miniot!!

lol, its good to know that someone cares. I have changed the mixture on the carbs so it should not be rich anymore.

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Howard: "You don't need a pen to be a writer Vince"
Vince: "I think you do"

How dirty is the air cleaner & also make sure your choke isn`t stuck on

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

My baby finally starts and goes!!! 4 new spark plugs did the job. Runs quite smoothly now. Thanks for all the advice.

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Howard: "You don't need a pen to be a writer Vince"
Vince: "I think you do"

Excellent o masked one. Did you sort out the sooting at all? I had similar issues when I ran SU's and took me weeks to nut it out...lol

Perseverance is noble...

Hooroo

Rob Forsyth
Miniot!!

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Rob Forsyth
Miniot!!

Ahh thats not a mask mate, thats really what my face looks like.

Anyway... I have reset the mixture settings on the carbs and did the piston test thingo and the engine revved up and dropped down to idle, so all is well.

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Howard: "You don't need a pen to be a writer Vince"
Vince: "I think you do"

Dixon sorry about this OT post aswell.. But I've just obtained the second season of The Mighty Boosh!! The first episode is funny! Can't wait to see the rest. You seen the second yet?