.

leaky carb

For any problems you have and advice you need!

Moderators: Club Admins, Minifinity Staff

leaky carb

Postby tomdale86 on Tue 9th Mar 2010, 09:41pm

hey guys!

im in some matching head-scatching with my carb!

basically it leaks oil, even when the car is not running, at a rate of the dashpot in about an hour or two. so i have to top it up everytime i use the car! i've had a look around the float chamber, doesnt seem to be coming from there.

today involved filling the dashpot up a couple of times to try and source the leak. this meant more oil 'disappeared' somewhere. (it doesnt end up on the floor)

i noticed when i started it up later after all that more white smoke than normal came out of the exhaust (there is normally a little bit).

does this mean that the dashpot oil is leaking into the manifold?

if not, or if so (!), what can and should i do about it!!??

please help! :?:
tomdale86
 
Posts: 10
Joined: Tue 9th Mar 2010, 09:37pm

Re: leaky carb

Postby nightrain on Tue 9th Mar 2010, 10:36pm

Oil is only supposed to be in the pistons hollow tube, not the top part of the carb. If the punger still hard'ish/stiff'ish to pull out. The only oil thats disappeared is the excess.
User avatar
nightrain
 
Posts: 3828
Joined: Sat 26th Nov 2005, 01:31am

Re: leaky carb

Postby tomdale86 on Tue 9th Mar 2010, 10:49pm

thanks.

i normally top it up just above the shoulder of the dashpot (so i can see its topped up).

The level will visibly run down in front of my eyes, without the car running.

if i dont top it up though, the car wont start very well, where as topped up as above it will start first time.

im really confused as to what is causing the leak when the car is off.
tomdale86
 
Posts: 10
Joined: Tue 9th Mar 2010, 09:37pm

Re: leaky carb

Postby bisto48 on Wed 10th Mar 2010, 12:30am

Carb sounds very worn to me! The oil must be going down the sides of the plunger bit (forgotten what its called) and is then entering the venturi of the carb. This is backed up by the white smoke you see. This is the oil being sucked up by the intake stroke and burning in the engine!

A new/second hand carb might be needed to rectify this problem
User avatar
bisto48
 
Posts: 89
Joined: Sun 9th Nov 2008, 01:58pm
Location: Oxford/ Worcester
Tag Line: It may smoke well but my god does it shift!

Drives: 1293cc Austin Mini city E
Seat Ibiza FR 130 TDI


Re: leaky carb

Postby nightrain on Wed 10th Mar 2010, 12:45am

Sounds like some idiot has tried to get the needle out, by belting a screw driver down the tube, fracturing the bottom and causing a leak.
User avatar
nightrain
 
Posts: 3828
Joined: Sat 26th Nov 2005, 01:31am

Re: leaky carb

Postby minimaniac on Wed 10th Mar 2010, 08:28am

nightrain wrote:Sounds like some idiot has tried to get the needle out, by belting a screw driver down the tube, fracturing the bottom and causing a leak.


Yup, hence the smoke from the exhaust.

Where are you based ?

BTW welcome to Minifinity :D
User avatar
minimaniac
 
Posts: 2959
Joined: Thu 24th Mar 2005, 04:36pm
Location: The Glorious North West
Tag Line: My ambition is to have enough time to get bored!

Drives: Minis (and not much else)


Re: leaky carb

Postby tomdale86 on Wed 10th Mar 2010, 10:36am

hey

so this morning ive taken the bell chamber and the piston off. anyone know how to separate these?

its a bit mucky generally-some sooty stuff underneath all that on the part of the carb still attached to the car.

also the dampner has some score marks on it. is this a problem?

the dampner isnt to do with the leak i know, as it leaks when the car is standing and without the dampner in!
tomdale86
 
Posts: 10
Joined: Tue 9th Mar 2010, 09:37pm

Re: leaky carb

Postby Nozzle on Wed 10th Mar 2010, 10:42am

bisto48 wrote:Carb sounds very worn to me! The oil must be going down the sides of the plunger bit (forgotten what its called) and is then entering the venturi of the carb. This is backed up by the white smoke you see. This is the oil being sucked up by the intake stroke and burning in the engine!


I thought a symptom of oil being burned in the engine was blue smoke, and a sympton of more water in the exhaust was more white 'smoke'?
User avatar
Nozzle
 
Posts: 508
Joined: Thu 3rd Jan 2008, 11:51am
Location: Woodbridge, Suffolk
Drives: 1995 Rover Cooper SPi
1966 Morris Countryman


Re: leaky carb

Postby tomdale86 on Wed 10th Mar 2010, 10:51am

ditto hence my confusion!

although, if you accidentally get oil on your exhaust, eg manifold, that burns off grey/white.
tomdale86
 
Posts: 10
Joined: Tue 9th Mar 2010, 09:37pm

Re: leaky carb

Postby tomdale86 on Wed 10th Mar 2010, 11:40am

so i filled the bell chamber/dashpot up (with the piston and needle attached still) and the oil leaked down the needle!

how caused/how fix!?

at least i know where its leaking now!
tomdale86
 
Posts: 10
Joined: Tue 9th Mar 2010, 09:37pm

Re: leaky carb

Postby bisto48 on Wed 10th Mar 2010, 12:07pm

when my valve guides went on mine (due to me being a pilock and not measuring things) the smoke it kicked out was white but smelt of oil. The head gasket was fine when i rebuilt the engine.
User avatar
bisto48
 
Posts: 89
Joined: Sun 9th Nov 2008, 01:58pm
Location: Oxford/ Worcester
Tag Line: It may smoke well but my god does it shift!

Drives: 1293cc Austin Mini city E
Seat Ibiza FR 130 TDI


Re: leaky carb

Postby themaninthesuitcase on Wed 10th Mar 2010, 12:26pm

Moved to Repairs and Servicing.
User avatar
themaninthesuitcase
 
Posts: 13457
Joined: Sun 28th Nov 2004, 07:21pm
Location: Brooklands
Tag Line: Tesco value Jack Osbourne.

Drives: Clubby estate (broken), Audi A3.

xbox live tag: PS3 - maninsuitcase


Re: leaky carb

Postby minimaniac on Wed 10th Mar 2010, 02:03pm

tomdale86 wrote:so i filled the bell chamber/dashpot up (with the piston and needle attached still) and the oil leaked down the needle!

how caused/how fix!?


As Nightrain says it's usually caused by someone trying to knock the needle out. :roll:

As for cure? As far as I know it can't be done (but I'm willing to be proved wrong :wink: )

Hence the question 'where are you based'?
User avatar
minimaniac
 
Posts: 2959
Joined: Thu 24th Mar 2005, 04:36pm
Location: The Glorious North West
Tag Line: My ambition is to have enough time to get bored!

Drives: Minis (and not much else)


Re: leaky carb

Postby tomdale86 on Wed 10th Mar 2010, 02:16pm

cheers.

right its back together, seems ok.

the reason i took the thing apart is that the car is troublesome starting sometimes, when i thought the carb was using oil (i think i may have been filling it too high )

when i had topped the dashpot up, probably over the top and round the sides leaking out, the car starts much better (first time).

can anyone explain this to me?

im in london btw
tomdale86
 
Posts: 10
Joined: Tue 9th Mar 2010, 09:37pm

Re: leaky carb

Postby nightrain on Wed 10th Mar 2010, 03:45pm

Guessing as we know nothing else about your engine, the jet is worn oval and so isn't able to meter the fuel correctly.
User avatar
nightrain
 
Posts: 3828
Joined: Sat 26th Nov 2005, 01:31am


Return to Repairs & Servicing

Who is online

Registered users: Alexa [Bot], Ask Jeeves [Bot], Google [Bot], MSN [Bot], SpyII, Yahoo [Bot]