Compression tested with plugs out.
#1 - 150 psi
#2 - 160
#3 - 170
#4 - 150

i will try cleaning the jets out tomorrow.
Thanks for all the replies.

Ok. So this morning I cleaned the jets with carby cleaner and compressed air. This didn't help. It sounds like the engine is running on only 3 cylinders or something...

I put some new plugs in cylinders 1 and 2, ran the engine and they stayed clean. when i put those same plugs in 3 and 4, ran the engine they came back dirty....

I took the rocker cover off to make sure that aall the valves are opening, which they are. The rocker gaps seem ok using a .017 feeler gauge. Not sure what they should be set to as I don't know what cam is in there.

I can't think of anything else other than head gasket.

Should I just take it down to mini clinic just around the corner? Or is it worth pulling the head off first?

I haven't had much luck with looking at the carby, so I started to take the head off.

Is it normal for the extractors to pull right out?


I undid the manifold bolts and I just pulled the extractors right off.... If these weren't sealed right would this cause the missing and problematic firing?

The head came off relatively easily. There are a couple of areas of concern. The inlet valves of cylinder 1 and 2 are looking quite white. Does this mean they are running lean?



Also the pistons have a lot of carbo build up. Should I clean thee up while apart?

What does the number on the top of the piston indicate?

I'd put a clamp on the extractors if they are a loose fit..


1&2 look leaner than the others, i wouldn't worry about the carbon build up just leave it as is.

The numbers on the pistons are usually oversize value eg. +60thou etc

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Starlet Conversion:
http://www.ausmini.com/forums/viewtopic.php?t=15484

i can`t see why you took the head off,,, it even looks like the gasket has been sealing quite well

who told you to take the head off??? or did you just do it for curiosity sake??/

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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.

More for curiosity sake. The gasket was sealing really well. It is a BK450 type.

I gave the weber a good clean out and checked all the connections.

I found a sheared bolt on the exhaust mount at the bottom of the gearbox, so it was kind of good that I did take the head off. That took a bit of time to get out...

I will finish torquing it all up tomorrow and if it is still missing/running lean, I will take it to a mini specialist to sort out...

I don't know what else to look for...

i have a pulsar distributor, does it have a condensor?

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1975 Leyland Mini: 1060cc - resto/ ex-hsc project.

No condenser on a Pulsar electronic.

Just a thought- check the valve guides in those 2 carboned cylinders. Mine did that once on one cylinder, I found the inlet guide worn.

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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.

nah,,, no condensor in them,,, maybe i`m wro,,,wr,,,wro,,, oh whatever it was just a guess

what carby do you have then Leighton?

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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.

Turns01,,, 3&4 don`t really look "That" black to me,,, hard on the net via a photo but still,,, 1 & 2 look a little "too" clean for my liking

i`d still be checking for an air leak on the """manifold to cylhead"""
or the """weber to manifold""""

or blocked-ish jets

you havn`t bumped the distributor shaft by any chance bending it maybe???

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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.

Thanks for all your help guys.

I put the head back on this morning and made sure all surfaces were clean and gasket seals were good. I cleaned out the carby and tightened up the exhaust.

Once it was all back together it ran well. No more spluttering.

I think I will take it somewhere to tune the weber, as a few of the adjusters have been moved slightly.

Thanks again for all your help.

Simon