Check the compression on #3 and #4 first. Usually when these 2 are not working on a smallbore, the gasket is blown between them. However it could be other things if not run for a while. Like suppression type plug leads gone open circuit coz they are too old.

[edit] typos...

_________________
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.

Well answering after the Doc is scary but here goes , try the easy things first .Make sure your getting fuel to both carbies .

So 1 do docs suggestions .

2 just some ideas im throwing out there i would check both bowls are full of petrol ,check dashpot oil is at the correct level check linkages and cables as your running dual carbies , Fuel filter installed ? as you said they probably have only done a few hours since rebuild so ......

....... and this is how i got pickles running and not for the squeamish have some one pour petrol down the carbies till she fires " mum did it for me " didnt mention blow back can cause a fire in your pouring cup as happened on an old xw ford of mine many many years ago " ahh good times ", as i said it worked for pickles but i only have a single carby .

Try simple stuff first then worry if that didnt work thats my theory anyway then ask Doc and the many many mini masters on here.

Cheers Bill

_________________
Project Pickles is ALIVE!!!!! Click Here!
Success is so much sweeter after the struggle

So already done:

Check leads (swapped with one and two)
Swapped Spark Plugs
Checked for Spark
Clamped fuel line to the carby on the right, made no difference.


Hmmm, compression WOOO! Fun, will check it out tomorrow If I can find the tester somewhere, any ideas on what its meant to be? My guess for old cars is above zero?

I have to say I love how easy it is to crank the engine over in the engine bay, it makes all this ALOT easier to do by your self.

Thanks for all your help.

If you can't find the tester stick yer thumb over each plughole in turn whilst someone cranks it. It'll be obvious if the gasket's blown, there will be sfa pressure in both those cylinders.

_________________
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.

If the carbies haven't been used for a while I would just give them a good clean
Probably just some crud stuck somewhere
First remove the lids of the float bowls and check for fuel
Then remove the damper and check the needle moves up and down
I would also remove the top and check all is ok with the needle and jet
Not much else but clean out and make sure it has fuel

_________________
1969 Cooper "S"
1967 Mini Deluxe
1973 Clubman Van (the fleet spare)
1978 ex 1275 LS ("Wizard" Eaton Supercharged)
2015 HSV GenF GTS(occasional drive & tow car)
2019 MINI F55 Cooper S

90% certain it's in the back of the Escort



Time to get out a manual and make sure I know which part is which But thank you very much for the suggestions.

So compression is fine.

Pulled apart the carby and everything appears to be fine and working properly, put it back together and tried to start it.

Wouldn't quite start so dad said to put something over the intake to act as a choke (choke cable not hooked up at the moment I have lost the screw).

So I did that, started up straight away, running on all 4, but when I take the thing (old t-shirt) off the intake it goes back to running on 1&2.....


Any suggestions guys?


Cheers,
Jordan

The carb could be too lean, and because of the siamesed centre bores they are leaning out past the point they can fire.

You could try get your hands on one larger carb, this would eliminate charge robbing as a culprit.

You didn't tell us what twins you had?

Which cylinders are the "siamesed centre bores"?

_________________
Steve

Twin 1&1/2" SU's (I think) they're bigger than the standard Cooper S ones which I think are 1&1/4?

Police coopers had the inch and a half carbs and standard had the inch and a quarter carbs.

Hooroo

_________________
Rob Forsyth
Miniot!!