Irish Mini Owners Club

Hi folks, I'm new to this game so be patient with me. Have a 1980 GT, original Dublin car. Was running fine last summer but then laid up for a few months. When I fired it up recently it was only running on 2 cylinders. Have changed plugs,dizzy, rotor arm and leads. No joy. Then replaced head gasket...and now it runs on the OTHER TWO cylinders. Compression seems fine, (was rebored at some stage to plus 20's, no discernable air leaks. Pulling my hair out at this stage. Any mechanical gurus out there with advice.
Mke H.

Welcome from a fellow 1980 GT owner! Not much advice for you as you seem to have tried everything, but somebody on here will be able to point you in the right direction

Is there a spark at the plugs of the 2 cylinders that aren't working ?

How are yis ? Yep, sparking on all 4. Firing order correct also. Have a feeling it's something really simple and probably blindingly obvious...no doubt someone will tell me. I assume that if the vacuum advance wasn't working correctly it wouldn't have such a disasterous affect...or am I wrong ?

If you have a spark, then the problem is either fuel or pressure. Have you done a compression test ?

If it was fuel I would have thought that it would affect all cylinders ??? Haven't done compression test yet...just borrowed a gauge, so hope to spend a day working on it in the next week or two. While I had the head off, I filled the bores with a light oil and left it for a few days. Level remained the same, so kidda ruled out sticking rings.

The engine just needs fuel, compression and then a spark to ignite the whole thing, if you have the spark, it has to be one of the other two, if the plugs are getting wet with petrol, then the problem has to be pressure related.

I presume it's missing on 2 and 3, is it ?

Hello again. Running on 1 and 2 only.

How have you diagnoised which 2 cylinders its running on each time?

Is it single or twin carb? Either way, are the plugs in the missing cylinders getting wet?

Billy

ok tigert100p, as the lads said it is a simple diagnoisis if you have a spark on the two cylinders that are not firing then its fuel or compression.
if you have compression then its fuel and if the engine is running on two cylinders its not the carb it has to be an inlet valve or a blocked inlet port after that your car has invented a new way to elimnate the fire triangle you should get on to the fire deparment and the patent office.
so do a compression test and get back to us.
Regards,
Good Look
Paul.

HAVE YOU CHECKED THAT THE POINTS ARE OPENING AT EACH LOBE OF THE DISTRIBUTOR CAM, IE THAT THE SHAFT IS NOT BENT.

ALSO ARE YOU CERTAIN THAT SOME HUMOURIST HAS NOT SWAPPED THE PLUG LEADS.

I MISSED WHETHER THE CAR HAS TWIN CARBS, IF SO WHEN IT IS RUNNING IS THE EXHAUST ON THE MISSING CLYINDER GETTING HOT OR IS IT STONE COLD

HOPE YOU ARE SUCCESSFUL

MINI HA HA

Hi Mini haha, It's on a single SU. Points are bang on although I hadn't considered the possibility of a bent shaft in the distributor...more food for thought. have borrowed a compression tester and hope to dedicate a day to it next week. Mick.

I had a similar problem with a bent shaft on a distributor earlier in the year on an old Triumph I have. For some reason we couldn't get spark to one cylinder despite points, lead and plug changes. No matter how many times you gapped the points, it would never give the same gap twice. A new distributor (thanks to Ebay) sorted it!

Billy

CASE CLOSED>>>Changed the distributor and it ran ok. Can't see anything wrong with the old one tho. Now sold as I bought a bright YELLOW clubman from Trim (I'm sure you'll all know the car). have a 1275 from a 91 cooper which I eventually intend putting into it. Thanks for all the advice. Mike.

well done mike may she tide you well and never rust

aaaaggg MUCH