42 replies to this topic

[Philfy]

Hi All,

I am new to the forum (well new to posting a question anyway)...

I have a problem with my mini not starting and really need some help.

firstly a bit of background....

I have 2 minis, a 1993 italian job, and a 1979 1275 GT

The GT was a runner (replacment engine from 1990) but needs alot of work, so really is at the start of a resto job.

1993 mini is a 1275, HIF38, electronic ignition, stage 1 kit, ( I have also fitted remote central locking, its very cool, but thats another story )

I got the 1993 mini on the road last year, and my wife has been using it every day since.

Starts first time every time..

was last used on friday last week, Monday morning this week, would not start, and also could smell petrol.

 

Monday evening I took a look, and could not get it to start. but couldn't see any leaks.

I have tested for a spark, thats fine. (out of desperation tried the distributor from GT engine, same electronic type) still would not start. (at this point I have to assume all timings are good)

also, after each time trying to start, took out plugs and nitice how wet with fuel they were)

 

then i suspected fuel in the oil, thinking it could be a fault in the carb, I swapped it for a HIF44 (again from the GT engine)

this time i got it to start once, but was making a loud screaming sound (which I am now thinking is because of the lack of oil in the bore because of the petrol seeping down) then it cut out and would not start again,

 

Tonight I have drained the oil, and sure enough, loads of fuel in the oil (somewhere between 1/4 and 1/2 tank since filled up friday)

I also took out the plugs, and while thinking what to do next, fuel started overflowing out of no 2 spark plug hole.

 

Does anyone have any ideas what could cause the fuel to syphon into the cylinders in that way?

what stops fuel flow while the car is not running?

 

anyway, if you have got this far, thanks for reading and I hope someone can help.

 

 

 

 

 

[Alex_B]

The diaphragm in the fuel pump if you have a mechanical pump on the back of the engine has likely failed which means the fuel gets pumped straight into the oil, I would be checking for this personally first :) 

[lrostoke]

I'd 2nd fuel pump, cant see anyway it would be getting in through the carb in those quantities

[Carlos W]

Has it got a mechanical or electric fuel pump?

[KernowCooper]

Cant see how fuel is running out the cylinder as the needle valve would shut off  when the float bowl is full? if its in the sump then its coming in via the fuel pump diaphram so a new pump and then reasemble. different story if you have a electric pump and the needle valves fauly then it could indeed flood the engine with a percentage getting in the engine oil, but it would have been running real rough if at all.

[Gremlin]

If your drive is steep enough so that the tank is above the jet in the carb, when you turn it off the fuel will continue to flow as it will jast syphon through, but as kernow cooper was saying, the needle valve might be damaged, so it will continue syphoning, I don't know what pump you've got, but if it is electrical, the design of the pump may allow fuel through when not energised, so it does make sense, but your pretty unlucky if this has happened!

[sledgehammer]

but was making a loud screaming sound

loads of fuel in the oil (somewhere between 1/4 and 1/2 tank since filled up friday)

I also took out the plugs, and while thinking what to do next, fuel started overflowing out of no 2 spark plug hole.

 

+1 to the on a hill / drive theory above ^^^^ - Had a Lancia that would do similar if parked a certain way when hot weather - but not to that extent

 

Hot weather - fuel tank vent blocked , + float valve weak ? -  firstly remove fuel filler cap - any pressure ?

 

he drained the oil - then petrol leaking out of the spark plug hole - so not manual fuel pump diaphram fail also tell tale hole would pis$$ fuel - unless blocked

 

electric pump would need to be running to pump fuel ? - but both valves would permit flow if pressure enough - same with manual

 

my guess - tank is pressurised in hot weather (vent blocked) forcing fuel thru the pump - and thru a weeping float valve

 

worrying thing - exhaust may have a fair bit of petrol in it if you have been cranking engine - prepare for a pop - or a dead cat - if it has one

 

all the above is just a guess - a bit too wierd - never seen petrol coming out a plug hole - other than a mist

Edited by sledgehammer, 23 July 2013 - 10:06 PM.

[Gremlin]

but was making a loud screaming sound
loads of fuel in the oil (somewhere between 1/4 and 1/2 tank since filled up friday)
I also took out the plugs, and while thinking what to do next, fuel started overflowing out of no 2 spark plug hole.

 
+1 to the on a hill / drive theory above ^^^^ - Had a Lancia that would do similar if parked a certain way when hot weather - but not to that extent
 
Hot weather - fuel tank vent blocked , + float valve weak ? -  firstly remove fuel filler cap - any pressure ?
 
he drained the oil - then petrol leaking out of the spark plug hole - so not manual fuel pump diaphram fail also tell tale hole would pis$$ fuel - unless blocked
 
electric pump would need to be running to pump fuel ? - but both valves would permit flow if pressure enough - same with manual
 
my guess - tank is pressurised in hot weather (vent blocked) forcing fuel thru the pump - and thru a weeping float valve
 
worrying thing - exhaust may have a fair bit of petrol in it if you have been cranking engine - prepare for a pop - or a dead cat - if it has one

I thought you meant cat as in if Fluffy was sunbathing behind it

[sledgehammer]

We know Mini's are ***stars***

[Carlos W]

Minis are **** anyway, just buy a subaru with an ej20 and no shtty carbs

Then why are you a member of the mini forum?

[KernowCooper]

Because he wants something better than a scooby

[Alex_B]

Minis are **** anyway, just buy a subaru with an ej20 and no shtty carbs

Yep, they can be "****" but no worse than any other classic and I hardly think a scooby can compare to the pure driving fun you get from the mini. 


and carbs are awesome, cant beat a weber for racing pedigree and performance for money! 

[Captain Mainwaring]

If the diaphragm had holed that much to fill the sump with fuel - there is no way it would have been able to lift fuel to the carb.

 

My guess is that the fuel pump is OK (it's a two minute check anyway - block the delivery line, pump it and see if it holds pressure - if it has an external priming doofer, this will stay loose, if not, wait a few mins and unblock the deliver and see if fuel splodges out).

 

I think you've got a leaking carb float and a either a pressurized tank or it's feeding by gravity.

 

Bore wash can certainly cause a car to loose compression enough that it won't start - common fault on some petrol fuel injected jags - if you start them, you have to see them up to temp, if not you'll never get them started again without messing about.

 

More worrying is that this is past the bore was stage - there has been enough fuel in the pots to cause hydraulic'ing with the possibility of a bent rod. I'm not sure if a mini starter has enough guts to bend a rod, but be aware it's possible.

[Captain Mainwaring]

Minis are **** anyway, just buy a subaru with an ej20 and no shtty carbs

 

Remind me which scoobies blow their head gaskets on the left hand bank every 22 seconds and need half the car taken to bits to fix it?

 

Minis may be old junk, but they are British junk - at least most of the owners didn't have to import the source of their torture....you had to pay extra for your version of Tenko.

[Philfy]

Thanks for all the replys guys.

its a mechanical fuel pump.

I would agree with the comments about the angle of the driveway, yes it has a small slope downwards...

but the car has been used for a year now and always parks in the same place, and never happened before.

 

was running fine until this happened.

needle in carb faulty...changed carb, so same fault twice? not sure.

 

Fuel pump is somthing i can try, but if its role is to pump, is there somthing that can fail inside to allow fuel through when not pumping?

 

pressurised fuel tank..possible, but ive lost 1/2 tank of fuel into the sump?

where is the fuel tank vent?